As filed with the Securities and Exchange Commission on March 29, 2019

Registration No. 333-                 

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM S-8

REGISTRATION STATEMENT UNDER THE

SECURITIES ACT OF 1933

CYCLERION THERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)

Cyclerion Therapeutics, Inc. 2019 Equity Incentive Plan

Cyclerion Therapeutics, Inc. 2019 Employee Stock Purchase Plan

Cyclerion Therapeutics, Inc. Amended and Restated 2010 Employee, Director and Consultant Equity Incentive Plan

Cyclerion Therapeutics, Inc. Amended and Restated 2005 Stock Incentive Plan
(Full titles of the plans)

William Huyett
301 Binney Street
Cambridge, Massachusetts 02142

(Name and address of agent for service)

(857) 327-8778

(Telephone number, including area code, of agent for service)

Please send copies of all communications to:

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.  o

CALCULATION OF REGISTRATION FEE

(1) Pursuant to Rule 416(a) under the Securities Act of 1933, as amended (the “Securities Act”), this Registration Statement also covers such additional shares of Common Stock as may be issued to prevent dilution resulting from stock splits, stock dividends and similar transactions.

(2) Pursuant to Rules 457(c) and 457(h)(1) under the Securities Act, the proposed maximum offering price per share and the maximum aggregate offering price for the shares have been calculated solely for the purpose of computing the registration fee on the basis of the average high and low prices of the Common Stock trading on a “when issued” basis as reported by the Nasdaq Global Select Market on March 22, 2019.

(3) Represents shares of Common Stock authorized for issuance under the Cyclerion Therapeutics, Inc. 2019 Equity Incentive Plan (the “2019 Incentive Plan”).

(4) Represents shares of Common Stock authorized for issuance under the Cyclerion Therapeutics, Inc. 2019 Employee Stock Purchase Plan (the “2019 ESPP”).

(5) Represents shares of Common Stock authorized for issuance under the Cyclerion Therapeutics, Inc. Amended and Restated 2010 Employee, Director and Consultant Equity Incentive Plan (the “2010 Plan”).

(6) Represents shares of Common Stock authorized for issuance under the Cyclerion Therapeutics, Inc. Amended and Restated 2005 Stock Incentive Plan (the “2005 Plan” and, together with the 2019 Incentive Plan, the 2019 ESPP and the 2010 Plan, the “Plans”).

PART I

INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

As permitted by Rule 428 under the Securities Act, this Registration Statement omits the information required by Part I of Form S-8.  The documents containing the information specified by Part I will be delivered to the participants of the Plans as required by Rule 428(b).  Such documents are not being filed with the Securities and Exchange Commission (the “SEC”) as part of this Registration Statement or as prospectuses or prospectus supplements pursuant to Rule 424 under the Securities Act.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.   Incorporation of Documents by Reference.

The following documents filed by Cyclerion Therapeutics, Inc. (the “Registrant”) with the SEC are incorporated herein by reference:

(1) The Registrant’s Registration Statement on Form 10 (File No. 001-38787), as filed with the SEC under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), on March 11, 2019 (the “Form 10”);

(2) The Registrant’s Current Report on Form 8-K (File No. 001-38787) filed with the SEC on March 19, 2019; and

(3) The description of the Registrant’s Common Stock contained in the Information Statement filed with the SEC as Exhibit 99.1 to the Form 10, including any amendments or reports filed for the purpose of updating such description.

All documents subsequently filed by the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act prior to the filing of a post-effective amendment to this Registration Statement that indicates that all securities offered have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference herein from the date of filing of such documents.  Any statement contained herein or in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for the purposes of this Registration Statement to the extent that a statement contained herein or in any subsequently filed document that also is or is deemed to be incorporated by reference herein modifies or supersedes such earlier statement.  Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute part of this Registration Statement.

Item 4. Description of Securities.

Not applicable.

Item 5. Interests of Named Experts and Counsel.

Not applicable.

Item 6. Indemnification of Directors and Officers.

The Registrant’s restated articles of organization contain provisions that limit the liability of its directors for damages for any breach of fiduciary duty to the fullest extent permitted by law.  The Registrant’s amended and restated bylaws also provide that it will indemnify, and advance funds to and reimburse expenses of, its directors and officers that have been appointed by its board of directors to the fullest extent permitted by law, and that it may indemnify, and advance funds to and reimburse expenses of, such other officers and employees as determined by its board of directors.  The right of indemnification provided under the Registrant’s amended and restated bylaws is in addition to and not exclusive of any other rights to which any of its directors, officers or any other persons may otherwise be lawfully entitled.  The Registrant expects to enter into indemnification agreements with its directors and executive officers, and it will carry insurance policies insuring its directors and officers against certain liabilities that they may incur in their capacity as directors and officers.

Part 8 of the Business Corporation Act of the Commonwealth of Massachusetts, (the “MBCA”), authorizes the provisions, described above, that are contained in the Registrant’s restated articles of organization and amended and restated bylaws.  In

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addition, Sections 8.30 and 8.42 of the MBCA provide that if an officer or director discharges his or her duties in good faith and with the care that a person in a like position would reasonably exercise under similar circumstances and in a manner the officer or director reasonably believes to be in the best interests of the corporation, he or she will not be liable for such action.

Item 7. Exemption from Registration Claimed.

Not applicable.

Item 8. Exhibits

Item 9. Undertakings.

(a) The undersigned Registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the Registration Statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the Registration Statement.  Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of a prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement;

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the Registration Statement or any material change to such information in the Registration Statement; provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) above shall not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed with or furnished to the Commission by the Registrant pursuant to Section 13 or 15(d) of the Exchange Act that are incorporated by reference in the Registration Statement.

(2) That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

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(b) The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the Registrant’s annual report pursuant to Section 13(a) or 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in the Registration Statement shall be deemed to be a new Registration Statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(c) Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable.  In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act, the registrant has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Boston, Massachusetts, on the 29th day of March, 2019.

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POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Peter Hecht, William Huyett and Larry Miller, and each of them, his or her true and lawful attorney-in-fact and agent, with full power of substitution and revocation, for him or her and in his or her name, place and stead, in any and all capacities, to execute any or all amendments including any post-effective amendments and supplements to this Registration Statement on Form S-8 of Cyclerion Therapeutics, Inc., and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorney-in-fact and agent full power and authority to do and perform each and every act and thing requisite and necessary to be done, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorney-in-fact and agent, or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated:

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Exhibit 4.1

The Commonwealth of Massachusetts

William Francis Galvin

Secretary of the Commonwealth

One Ashburton Place, Boston, Massachusetts 02108-1512

RESTATED ARTICLES OF ORGANIZATION

(General Laws Chapter 156D, Section 10.07; 950 CMR 113.35)

(check appropriate box)

o the directors without shareholder approval and shareholder approval was not required;

OR

x the board of directors and the shareholders in the manner required by G.L. Chapter 156D and the corporation’s articles of organization.

(5) The following information is required to be included in the articles of organization pursuant to G.L. Chapter 156D, Section 2.02 except that the supplemental information provided for in Article VIII is not required:

ARTICLE I

The exact name of the corporation is:

Cyclerion Therapeutics, Inc.

ARTICLE II

Unless the articles of organization otherwise provide, all corporations formed pursuant to G.L. Chapter 156D have the purpose of engaging in any lawful business.  Please specify if you want a more limited purpose:

To engage in any lawful activity permitted of a corporation governed by the Massachusetts Business Corporation Act or any successor thereto.

ARTICLE III

State the total number of shares and par value, if any, of each class of stock that the corporation is authorized to issue.  All corporations must authorize stock.  If only one class or series is authorized, it is not necessary to specify any particular designation.

The Corporation is authorized to issue 500 million shares of capital stock of which 400 million are “Common Stock” and 100 million shares are “Preferred Stock.”

ARTICLE IV

Prior to the issuance of shares of any class or series, the articles of organization must set forth the preferences, limitations and relative rights of that class or series.  The articles may also limit the type or specify the minimum amount of consideration for which shares of any class or series may be issued.  Please set forth the preferences, limitations and relative rights of each class or series and, if desired, the required type and minimum amount of consideration to be received.

A.                                    AUTHORIZED CAPITAL STOCK

The total number of shares of all classes of capital stock which the Corporation is authorized to issue is five hundred million (500,000,000) shares, consisting of four hundred million (400,000,000) shares of Common Stock and one hundred million (100,000,000) shares of Preferred Stock.  The board of directors, at any time or from time to time, may reclassify any unissued shares of any class or series of capital stock into one or more existing or new classes or series.

B.                                    DESCRIPTION OF COMMON STOCK

The holders of outstanding shares of Common Stock have the exclusive right to vote for the election of directors and on all other matters requiring action by the shareholders or submitted for action to the shareholders, except as may be provided herein, as may be associated with a series of Preferred Stock, or as may be otherwise required by law.  Each share of Common Stock shall entitle the holder thereof to one vote.

Subject to the terms of any outstanding series of Preferred Stock, the holders of outstanding shares of Common Stock are entitled to receive, to the extent permitted by law, such dividends as may from time to time be declared by the Board of Directors.

Upon any voluntary or involuntary liquidation, dissolution or winding up of the Company, the holders of Common Stock are entitled to receive the net assets of the Corporation, after the Corporation has satisfied or made provision for its debts and obligations and for payment to the

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holders of shares of any series of Preferred Stock having preferential rights to receive distributions of the net assets of the Corporation.

C.                                    DESCRIPTION OF PREFERRED STOCK

Shares of Preferred Stock may be issued from time to time in one or more series.  The Board of Directors shall determine, in whole or in part, the number, preferences, limitations or relative rights of any such series before the issuance of any shares of that series.

ARTICLE V

The restrictions, if any, imposed by the articles of organization upon the transfer of shares of any class or series of stock are:

None.

ARTICLE VI

Other lawful provisions, and if there are no such provisions, this article may be left blank.

A.                                    BOARD OF DIRECTORS

1.                                     Size.  The Board of Directors shall initially consist of a minimum of three directors, and the size of the Board of Directors may be increased or decreased, from time to time, to a size fixed, at the time, exclusively by the Board of Directors.  In no event will a decrease in the number of directors shorten the term of an incumbent director.  Notwithstanding the foregoing, and except as otherwise required by law, whenever the holders of any one or more series of Preferred Stock have the right, voting separately as a class, to elect one or more directors, the election, terms of office and other features of such directorships shall be governed by the terms of such series.  A director shall serve until his or her successor is elected and qualified, subject to prior death, resignation, retirement or removal.

2.                                     Vacancies.  Except as otherwise determined by the Board of Directors in establishing a series of Preferred Stock, any vacancies in the Board of Directors, including any vacancies resulting from the enlargement of the Board of Directors, shall be filled exclusively by the directors then in office, even if less than a quorum.

3.                                     Removal.  Except as otherwise determined by the Board of Directors in establishing a series of Preferred Stock, at any special meeting of the shareholders called at least in part for such purpose, any director or directors may, by the affirmative vote of the holders of at least a majority of the stock entitled to vote for the election of directors, be removed from office for cause.  In addition, except as otherwise determined by the Board of Directors in establishing a series of Preferred Stock, the Board of Directors is authorized, from time to time, to remove any director or directors, for cause, at a meeting of the Board of Directors, by vote of a

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majority of directors then in office.  The provisions of this subsection shall be the exclusive method for the removal of directors.

B.                                    SHAREHOLDER VOTE REQUIRED FOR CERTAIN ACTIONS

Except as otherwise determined by the Board of Directors in establishing a series of Preferred Stock, shareholder approval of the following actions shall require the affirmative vote of holders of a majority of all shares entitled to vote on such matter: (i) an amendment to these Restated Articles of Organization, (ii) the sale, lease, exchange, or other disposal of all or substantially all of the Corporation’s property, (iii) a merger or consolidation of the Corporation with or into any other entity; or (iv) a share exchange with any other entity.  Any such amendment, sale, lease, exchange, disposal, merger, consolidation, or share exchange shall also require approval by the Board of Directors.  This provision is not intended to, and shall not, create a requirement to obtain shareholder approval for matters that do not require shareholder approval under applicable Massachusetts corporation law.

C.                                    ADDITIONAL PROVISIONS

1.                                     The Board of Directors may make, amend, or repeal the bylaws in whole or in part, except with respect to any provision thereof which by law or these Restated Articles of Organization requires action by the shareholders.  To the extent permitted by law, the bylaws, including a provision adopted solely through action of the Board of Directors, may provide for a different quorum or voting requirement than is provided for in Chapter 156D of the Massachusetts General Laws or any successor statute.

2.                                     A director shall not be liable to the Corporation or its shareholders for damages for any breach of fiduciary duty, except to the extent that the elimination or limitations of liability is not permitted under law.  No amendment or repeal of this provision shall deprive a director of the benefits hereof with respect to any act or omission occurring prior to such amendment or repeal.

3.                                      The Corporation shall indemnify and hold harmless, to the fullest extent permitted by law as it presently exists or may hereafter be amended, each person, now or hereafter a director of the Corporation or an officer of the Corporation from and against any and all claims and liabilities to which he or she may be or become subject by reason of his or her being or having been a director or officer of the Corporation, or by reason of his or her alleged acts or omissions as a director or officer of the Corporation, and the Corporation shall indemnify and reimburse each such officer and director against and for any and all legal and other expenses reasonably incurred by him or her in connection with any such claims and liabilities, whether or not at or prior to the time which so indemnified, held harmless or reimbursed he or she has ceased to be an officer or director of the Corporation. The foregoing obligation includes payment by the Corporation of expenses incurred in defending a civil or criminal action or proceeding in advance of the final disposition of such action or proceeding.

The Corporation shall similarly indemnify and hold harmless persons who serve at its express written request as directors or officers of another organization, if such entity fails,

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directly or through insurance, to cover such costs and expenses; notwithstanding the foregoing, if such person may be entitled to be indemnified by such other organization or is insured by an insurer providing insurance coverage under an insurance policy issued to such other organization for liabilities, expenses or other losses as to which such person also would be entitled to be indemnified or have expenses advanced by the Corporation pursuant to the foregoing provisions of this Article VI.C.3, then it is intended, as between the Corporation and such other organization and/or its insurer, that such other organization and its insurer shall be the full indemnitor or insurer of first resort for any such liabilities, expenses or other losses, and that only thereafter may the Corporation be required to pay indemnification or advancement of any such liabilities, expenses or other losses.

The right of indemnification set forth in this Article VI.C.3 shall be in addition to and not exclusive of any other rights to which any officer or director of the Corporation may otherwise be lawfully entitled.  As used in this Article VI.C.3, the terms “officer” and “director” include their respective heirs, executors and administrators.

4.                                      Special meetings of shareholders may be called by the Board of Directors or the holders of at least 40% of all the votes entitled to be cast on any issue to be considered at the proposed special meeting.

5.                                     Unless the Board of Directors of the Corporation consents in writing to the selection of an alternative forum, a state or federal court located within the Commonwealth of Massachusetts shall be the sole and exclusive forum for (a) any derivative action or proceeding brought on behalf of the Corporation, (b) any action asserting a claim of breach of a fiduciary duty owed by any director, officer or other employee of the Corporation to the Corporation or the Corporation’s shareholders, (c) any action asserting a claim arising pursuant to any provision of the Massachusetts Business Corporation Act or any successor statute, or (d) any action asserting a claim governed by the internal affairs doctrine, in all cases subject to the court having personal jurisdiction over the indispensable parties named as defendants.  Any person or entity purchasing or otherwise acquiring any interest in shares of capital stock of the Corporation shall be deemed to have notice of and consented to this Article VI.C.5.

ARTICLE VII

The effective date of organization of the corporation is the date and time the articles were received for filing if the articles are not rejected within the time prescribed by law.  If a later effective date is desired, specify such date, which may not be later than the 90th day after the articles are received for filing:

N/A

It is hereby certified that these restated articles of organization consolidate all amendments into a single document.  If a new amendment authorizes an exchange, or effects a reclassification or cancellation, of issued shares, provisions for implementing that action are set forth in these restated articles unless contained in the text of the amendment.

Specify the number(s) of the article(s) being amended: Article III; Article IV; Article VI

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Signed by:

(signature of authorized individual)

o Chairman of the board of directors,

xPresident,

o Other officer,

o Court-appointed fiduciary,

on this 28th day of March, 2019.

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Exhibit 4.2

AMENDED AND RESTATED BYLAWS

of

CYCLERION THERAPEUTICS, INC.

ARTICLE I

Meetings of Shareholders

Section 1.                                           Place.  Meetings of the shareholders shall be held at the principal office of the corporation or at such other place as may be determined by the board of directors or an officer designated by the board of directors and identified in the notice to shareholders of such meeting.

Section 2.                                           Annual Meetings.  The annual meeting of the shareholders shall be held on such date determined by the board of directors and shall be at such time and place as the board of directors or an officer designated by the board of directors shall determine.

Section 3.                                           Special Meetings.  Subject to the rights of holders of any class or series of preferred stock of the corporation, special meetings of the shareholders may be called as provided in the articles of organization.

(a)                                 Requests.  In order for a special meeting upon shareholder request (a “Shareholder Requested Special Meeting”) to be called, requests for a special meeting (each a “Special Meeting Request”) must be signed by shareholders of record of the corporation (each, a “Record Shareholder”) (or their duly authorized agents) who beneficially own shares of capital stock having at least the requisite percentage of votes specified in the articles of organization (the “Requisite Percentage”) and delivered to the secretary at the principal executive offices of the corporation.  Each Special Meeting Request must (i) set forth a statement of the specific purpose(s) of the meeting and the matters proposed to be acted on at it, (ii) bear the date of signature of each such Record Shareholder (or duly authorized agent) signing the Special Meeting Request, (iii) set forth the name and record address of each such Record Shareholder, (iv) set forth the class and number of shares of capital stock of the corporation that are beneficially owned by each such Record Shareholder, and (v) include documentary evidence of each such Record Shareholder’s record and beneficial ownership of such stock.

(b)                                 Revocation.  Any Record Shareholder may revoke a Special Meeting Request at any time by written revocation delivered to the secretary.  If following such revocation there are un-revoked requests from Record Shareholders holding in the aggregate less than the Requisite Percentage, the board of directors, in its discretion, may cancel the special meeting.  If none of the Record Shareholders who submitted a Special Meeting Request appear or send a qualified representative to present the business proposed to be conducted at the special meeting, the corporation need not present such business for a vote at such meeting.

(c)                                  Conditions.  The secretary shall not be required to call a Shareholder Requested Special Meeting if (a) the stated business to be brought before the special meeting is not a proper subject for shareholder action under the corporation’s articles of organization, these bylaws or applicable law, (b) the board of directors has called or calls for an annual or special meeting of shareholders to be held within ninety (90) days after the date on which Shareholder Meeting Request(s) signed by Record Shareholder(s) who beneficially own the Requisite Percentage have been received by the secretary (the “Delivery Date”) and the purpose(s) of such meeting include the purpose(s) specified in the Special Meeting Request(s) or (c) an annual or special meeting was held not more than twelve (12) months before the Delivery Date, which included the purposes specified in the Special Meeting Request(s), with such determinations under (b) and (c) being made in good faith by the board of directors.

Section 4.                                           Notice.  A written notice of the date, place and time of each meeting of shareholders describing the purposes of the meeting shall be given by the secretary or an assistant secretary (or by any other officer who is authorized to provide notice of such meeting) no fewer than seven (7) nor more than sixty (60) days before the meeting date to each shareholder entitled to vote at the meeting and to each other shareholder to whom the corporation is required to provide such notice by deposit in the United States mail, postage prepaid, and addressed to such shareholder at the shareholder’s address as it appears in the records of the corporation, or by electronic transmission directed to such shareholder in such manner as the shareholder shall have specified to the corporation, including by facsimile transmission, electronic mail or posting on an electronic network.  Notwithstanding the foregoing, in the case of any Shareholder Requested Special Meeting, such meeting shall be scheduled not fewer than sixty (60) days nor more than ninety (90) days after the Delivery Date, and written notice thereof shall be given in accordance with the preceding sentence within thirty (30) days after the Delivery Date.  Whenever notice of a meeting is required to be given to a shareholder under applicable law, the articles of organization or these bylaws, a written waiver thereof, executed before or after the meeting by such shareholder and filed with the records of the meeting, shall be deemed equivalent to such notice.  In addition, any shareholder who attends the meeting (whether in person or by proxy) (a) without objecting to holding the meeting or transacting business at the meeting at the beginning of the meeting or promptly upon the shareholder’s arrival or who thereafter votes for or assents to action taken at the meeting waives objection to lack of notice or defective notice of the meeting or (b) without objecting to the consideration of a particular matter when it is presented waives objection that the matter is not within the purposes described in the notice for such meeting.

Section 5.                                           Shareholder Nominations of Directors.  Except as otherwise required by law, only persons who are nominated in accordance with the following procedures shall be eligible for election as directors.  Nominations of persons for election as directors at any annual meeting may be made by or at the direction of the board of directors (including through a committee delegated such function), or by any Record Shareholder entitled to vote for the election of directors who complies with the notice procedures set forth in this Section 5.  Such nominations, other than those made by or at the direction of the board of directors, shall be made pursuant to timely notice in writing to the chairperson of the board, if any, the chief executive officer (or, if there is no chief executive officer, the president) or the secretary.  To be timely, a shareholder’s notice must be delivered to or mailed and received at the principal executive offices of the corporation the earlier of: (a) not fewer than ninety (90) days nor more than one

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hundred and twenty (120) days prior to the anniversary date of the prior year’s annual meeting or, (b) with respect to the corporation’s 2020 annual meeting, during February 2020, or (c) if (i) there was no annual meeting in the prior year or (ii) the date of the current year’s annual meeting is more than thirty (30) days prior to or more than thirty (30) days after the anniversary date of the prior year’s annual meeting, sixty (60) days prior to the annual meeting; provided, however, that, if fewer than sixty-five (65) days’ notice or prior public disclosure of the date of the meeting is given or made to shareholders, notice by the shareholder to be timely must be so received not later than the close of business on the fifteenth (15th) day following the day on which such notice of the date of the meeting was deposited in the United States mail or sent by electronic transmission or such public disclosure was made.  Such notice from a shareholder must state (i) as to each nominee that the shareholder proposes for election or reelection as a director: (A) all information relating to such nominee that would be required to be disclosed in solicitations of proxies for the election of such nominee as a director pursuant to Regulation 14A under the Securities Exchange Act of 1934, as amended (the “Act”), and such nominee’s written consent (I) to be named as a nominee in the corporation’s proxy statement, proxy card, and/or ballot, if the corporation’s board of directors approves such inclusion and (II) to serve as a director if elected, and (B) a description of all direct and indirect compensation, reimbursement, indemnification and other material arrangements, agreements or understandings during the past three years, and any other material relationship, if any, between or concerning such shareholder and any Shareholder Associated Person (as defined below), on the one hand, and the proposed nominee, and his or her respective affiliates or associates, on the other hand, (ii) as to the shareholder making the nomination: (A) the name and address of the shareholder, (B) the class (and, if applicable, series) and number of shares of stock of the corporation that are, directly or indirectly, owned beneficially or of record by the shareholder or any Shareholder Associated Person, (C) any option, warrant, convertible security, stock appreciation right or similar right with an exercise or conversion privilege or a settlement payment or mechanism at a price related to any class (or, if applicable, series) of shares of stock of the corporation or with a value derived in whole or in part from the value of any class (or, if applicable, series) of shares of stock of the corporation, whether or not such instrument or right shall be subject to settlement in the underlying class or series of capital stock of the corporation or otherwise (each, a “Derivative Instrument”) directly or indirectly owned beneficially or of record by such shareholder or any Shareholder Associated Person and any other direct or indirect opportunity to profit or share in any profit derived from any increase or decrease in the value of shares of stock of the corporation of the shareholder or any Shareholder Associated Person, (D) any proxy, contract, arrangement, understanding or relationship pursuant to which such shareholder or any Shareholder Associated Person has a right to vote any securities of the corporation, (E) any proportionate interest in shares of the corporation or Derivative Instruments held, directly or indirectly, by a general or limited partnership in which such shareholder or any Shareholder Associated Person is a general partner or beneficially owns an interest in a general partner, (F) any performance-related fees (other than an asset-based fee) that such shareholder or any Shareholder Associated Person is entitled to based on any increase or decrease in the value of the shares of stock of the corporation or Derivative Instruments and (G) whether the shareholder intends to deliver a proxy statement and form of proxy to shareholders.  For purposes of these bylaws, a “Shareholder Associated Person” of any shareholder means (i) any “affiliate” or “associate” (as those terms are defined in Rule 12b-2 under the Act, or any successor rule thereto) of the shareholder that owns beneficially or of record any capital stock or other securities of the corporation and (ii) any person acting in

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concert with such shareholder or any affiliate or associate of such shareholder with respect to the capital stock or other securities of the corporation.  In addition, any nominee proposed by a shareholder shall complete a questionnaire, in a form provided by the corporation, within ten (10) days of receipt of the form of questionnaire from the corporation.  The chairperson of the meeting shall, if the facts warrant, determine that a nomination was not made in accordance with the foregoing procedures, and, if the chairperson should so determine, the chairperson shall so declare to the meeting and the defective nomination shall be disregarded.

Section 6.                                           Advance Notice of Shareholder-Proposed Business at Annual Meetings.  At an annual meeting of the shareholders, only such business shall be conducted as shall have been properly brought before the meeting.  To be brought properly before an annual meeting, business must be specified in the notice with respect to such meeting contemplated by Section 4 of this Article I (or any supplement thereto) or otherwise properly brought before the meeting by or at the direction of the board of directors.  In addition to any other applicable requirements, for business to be brought properly before an annual meeting by a shareholder, the shareholder must comply with the requirements of Rule 14a-8 under the Act, or any successor rule thereto, and, pursuant to such rule, have had such business included in the notice with respect to such meeting.

Notwithstanding anything in these bylaws to the contrary, no business shall be properly brought before the annual meeting except in accordance with the procedures set forth in this Section 6, provided, however, that nothing in this Section 6 shall be deemed to preclude discussion by any shareholder of any business properly brought before the annual meeting in accordance with this Section 6. The chairperson of an annual meeting shall, if the facts warrant, determine that business was not properly brought before the meeting in accordance with the provisions of this Section 6, and, if the chairperson should so determine, the chairperson shall so declare to the meeting and any such business not properly brought before the meeting shall not be transacted.

Section 7.                                           Proxy Access.

(a)                                 Inclusion of Shareholder Nominee in Proxy Statement.  Whenever the board of directors solicits proxies with respect to the election of directors at an annual meeting of shareholders, subject to the provisions of this Section 7, the corporation shall include in its proxy statement (including its form of proxy and ballot) for such annual meeting of shareholders, in addition to any persons nominated for election by the board of directors, including through a committee thereof, the name, together with the Required Information (as defined below), any person nominated for election to the board of directors submitted pursuant to this Section 7 (each a “Shareholder Nominee”) provided: (i) the shareholder has given timely written notice of such Shareholder Nominee satisfying the requirements of this Section 7 (the “Notice of Proxy Access Nomination”) to the secretary of the corporation by or on behalf of a shareholder or shareholders that, at the time the notice is delivered, satisfy the ownership and other requirements of this Section 7 (such shareholder or shareholders, and any person on whose behalf they are acting, the “Eligible Shareholder”), (ii) the Eligible Shareholder expressly elects in writing at the time of providing the notice to have its Shareholder Nominee included in the corporation’s proxy statement pursuant to this Section 7 and (iii) the Eligible Shareholder and the Shareholder Nominee otherwise satisfy the requirements of this Section 7.

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(b)                                 Timely Notice.  To nominate a Shareholder Nominee, the Eligible Shareholder must timely submit the Notice of Proxy Access Nomination to the secretary of the corporation at the principal executive offices of the corporation.  To be timely, the Notice of Proxy Access Nomination shall be delivered to the secretary at the principal executive offices of the corporation, no earlier than on one hundred and fifty (150) days and no later than one hundred and twenty (120) days prior to the first anniversary of the date of the preceding year’s annual meeting of shareholders, or, if the date of the annual meeting of shareholders is advanced by more than thirty (30) days or delayed by more than sixty (60) days from the anniversary of the preceding year’s annual meeting of shareholders, or if no annual meeting of shareholders was held in the preceding year, the Notice of Proxy Access Nomination must be so delivered not earlier than the close of business on the one hundred fiftieth (150th) day prior to such annual meeting and not later than the close of business on the later of the one hundred twentieth (120th) day prior to such annual meeting or the tenth (10th) day following the day on which public announcement of the date of such annual meeting is first made by the corporation. In no event shall the public announcement of an adjournment or postponement of an annual meeting of shareholders commence a new time period (or extend any time period) for the giving of a Notice of Proxy Access Nomination.

(c)                                  Information to be Included in Proxy Statement.  In addition to including the name of the Shareholder Nominee in the corporation’s proxy statement for the annual meeting of shareholders, the corporation shall also include (collectively, the “Required Information”): (i) as to each Shareholder Nominee, all information relating to such person that is required to be disclosed in solicitations of proxies for election of directors, or is otherwise required, in each case, by the Act (including such person’s written consent to being named in the proxy statement as a nominee and to serving as a director if elected) and (ii) if the Eligible Shareholder so elects, a written statement of the Eligible Shareholder (or in the case of a group, a written statement of the group), not to exceed five hundred (500) words, in support of its Shareholder Nominee, which must be provided at the same time as the notice for inclusion in the corporation’s proxy statement for the annual meeting of shareholders (a “Statement”).  Only one Statement may be submitted by an Eligible Shareholder in support of its Shareholder Nominee(s).  Notwithstanding anything to the contrary contained in this Section 7, the corporation may omit from its proxy materials any information or Statement that it, in good faith, believes would violate the Securities and Exchange Commission’s proxy rules or any other applicable law, rule, regulation or listing standard.  Additionally, nothing in this Section 7 shall limit the corporation’s ability to solicit against any Shareholder Nominee or include in the corporation’s proxy statement its own statement or other information relating to any Eligible Shareholder or any Shareholder Nominee.

(d)                                 Shareholder Nominee Limits.  The number of Shareholder Nominees (including Shareholder Nominees that were submitted by an Eligible Shareholder for inclusion in the corporation’s proxy statement pursuant to this Section 7 but either are subsequently withdrawn or that the board of directors decides to nominate (each, a “Board Nominee”)) appearing in the corporation’s proxy statement with respect to a meeting of shareholders shall be the greater of: (x) two (2); or (y) twenty percent (20%) of the number of directors in office (rounded down to the nearest whole number) (the “Permitted Number”) as of the last day on which a Notice of Proxy Access Nomination may be delivered pursuant to and in accordance with this Section 7 (the “Final Proxy Access Nomination Date”); provided, however, that: (i) in

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the event that one or more vacancies for any reason occurs on the board of directors at any time after the Final Proxy Access Nomination Date but before the date of the annual meeting of shareholders, and the board of directors resolves to reduce the size of the board of directors in connection therewith, the Permitted Number shall be calculated based on the number of directors in office as so reduced, and (ii) any Shareholder Nominee who is included in the corporation’s proxy materials for a particular meeting of shareholders but either (a) withdraws from or becomes ineligible or unavailable for election at the meeting or (b) does not receive at least twenty-five percent (25%) of the votes cast in favor of such Shareholder Nominee’s election, will be ineligible to be a Shareholder Nominee pursuant to this Section 7 for the next two annual meetings of shareholders following the meeting for which the Shareholder Nominee has been nominated for election.

(e)                                  Persons Considered in Calculation of Maximum Number of Shareholder Nominees.  The following persons shall be considered Shareholder Nominees for purposes of determining when the Permitted Number has been reached: (i) any Shareholder Nominee whose name was submitted for inclusion in the corporation’s proxy materials pursuant to this Section 7 but whom the board of directors decides to recommend as a Board Nominee, (ii) any Shareholder Nominee whose name is withdrawn and who is not replaced by a successor Shareholder Nominee by the applicable Eligible Shareholder prior to the Final Proxy Access Nomination Date and (iii) any director who had been a Shareholder Nominee at any of the preceding two (2) annual meetings and whose reelection at the upcoming annual meeting of shareholders is being recommended by the board of directors.

(f)                                   Ranking Shareholder Nominees.  Any Eligible Shareholder submitting more than one Shareholder Nominee for inclusion in the corporation’s proxy materials pursuant to this Section 7 shall rank such Shareholder Nominees based on the order that the Eligible Shareholder desires such Shareholder Nominees to be selected for inclusion in the corporation’s proxy statement.  If the number of Shareholder Nominees submitted by all Eligible Shareholders pursuant to this Section 7 exceeds the Permitted Number provided for in this Section 7, the highest ranking Shareholder Nominee from each Eligible Shareholder will be selected for inclusion in the corporation’s proxy materials until the Permitted Number is reached, proceeding in order of the amount (largest to smallest) of shares of common stock of the corporation each Eligible Shareholder disclosed as owned in its respective Notice of Proxy Access Nomination submitted to the corporation.  If the Permitted Number is not reached after the highest ranking Shareholder Nominee who meets the requirements of this Section 7 from each Eligible Shareholder has been selected, this process shall continue as many times as necessary, following the same order each time, until the maximum number is reached.

(g)                                  Eligibility of Nominating Shareholder; Shareholder Groups.  An Eligible Shareholder must have owned (as defined below) continuously for at least three (3) years (the “Minimum Holding Period”) a number of shares that represents three percent (3%) of the corporation’s outstanding common stock entitled to vote in the election of directors (the “Required Shares”) as of both the date the Notice of Proxy Access Nomination is received by the corporation in accordance with this Section 7 and the record date for determining shareholders entitled to vote at the meeting.  For purposes of satisfying the ownership requirement under this Section 7, the voting power represented by the shares of the corporation’s capital stock owned by one or more shareholders, or by the person or persons who own shares of the corporation’s

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capital stock and on whose behalf any shareholder is acting, may be aggregated, provided that: (i) the number of shareholders and other persons whose ownership of shares is aggregated for such purpose shall not exceed twenty (20), and (ii) each shareholder or other person whose shares are aggregated shall have held such shares continuously for the Minimum Holding Period.  Whenever an Eligible Shareholder consists of a group of shareholders and/or other persons, any and all requirements and obligations for an Eligible Shareholder set forth in this Section 7 must be satisfied by and as to each such shareholder or other person, except that shares may be aggregated to meet the Required Shares as provided in this Section 7(g).  With respect to any one particular annual meeting, no shareholder or other person may be a member of more than one group of persons constituting an Eligible Shareholder under this Section 7.

(h)                                 Funds.  A group of two or more funds shall be treated as one shareholder or person for this Section 7 provided that the other terms and conditions in this Section 7 are met (including Section 7(j)) and the funds are: (i) under common management and investment control, (ii) under common management and funded primarily by the same employer (or by a group of related employers that are under common control) or (iii) a group of “investment companies,” as such term is defined in Section 12(d)(1)(G)(ii) of the Investment Company Act of 1940, as amended.

(i)                                     Ownership.  For purposes of this Section 7, an Eligible Shareholder shall be deemed to “own” only those outstanding shares of the corporation’s capital stock as to which the person possesses both: (i) the sole power to vote, or direct the voting of, and to dispose of, or to direct the disposition of, the shares and (ii) the full economic interest in (including the opportunity for profit and risk of loss on) such shares; provided that the number of shares calculated in accordance with (i) and (ii) shall not include any shares: (A) sold by such shareholder (or any of its affiliates) in any transaction that has not been settled or closed, (B) borrowed by such person (or any of its affiliates) for any purposes or purchased by such person or any of its affiliates pursuant to an agreement to resell, or (C) subject to any option, warrant, derivative or other agreement or understanding, whether any such arrangement is to be settled with shares of common stock of the corporation or with cash based on the notional amount of shares subject thereto, in any such case which has, or is intended to have or if exercised would have, the purpose or effect of (a) reducing in any manner, to any extent or at any time in the future, such shareholder’s (or its affiliates’) power to vote or direct the voting and power to dispose or direct the disposition of any of such shares and/or (b) offsetting to any degree any gain or loss arising from the full economic interest in such shares by such shareholder (or affiliate). An Eligible Shareholder’s ownership of loaned shares shall only be deemed to continue during any period in which (x) the Eligible Shareholder has loaned such shares, provided that the Eligible Shareholder has the power to recall such loaned shares on not more than five (5) business days’ notice and recalls such loaned shares not more than five (5) business days after being notified that any of its Shareholder Nominee(s) will be included in the corporation’s proxy materials or (y) the Eligible Shareholder has delegated any voting power by means of proxy, proxy of attorney, or other instrument or arrangement that is revocable at any time by the Eligible Shareholder. Whether outstanding shares of common stock of the corporation are “owned” for these purposes will be determined by the board of directors.  For purposes of this Section 7, the term “affiliate” or “affiliates” shall have the meaning ascribed thereto under the Act.

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(j)                                    Nomination Notice and Other Eligible Shareholder Deliverables.  An Eligible Shareholder must provide with its Notice of Proxy Access Nomination the following information in writing to the secretary of the corporation: (i) in form and substance reasonably satisfactory to the corporation, verification that, as of a date within seven (7) calendar days prior to the date the Notice of Proxy Access Nomination is delivered to, or mailed to and received by, the secretary of the corporation, the Eligible Shareholder owns, and has owned continuously for the Minimum Holding Period, the Required Shares, and the Eligible Shareholder’s agreement: (A) to provide, within five (5) business days after the record date for the annual meeting, verification of the Eligible Shareholder’s continuous ownership of the Required Shares through the record date and (B) notify the corporation promptly if the Eligible Shareholder ceases to own the Required Shares prior to the date of the applicable annual meeting of shareholders, (ii) documentation in form and substance reasonably satisfactory to the corporation demonstrating that any group of funds being counted as one shareholder in meeting the definition of Eligible Shareholder are entitled to be treated as one shareholder for purposes of this Section 7, (iii) a copy of the Schedule 14N (or any successor form) that has been filed with the Securities and Exchange Commission as required by Rule 14a-18 under the Act (or any successor provisions), (iv) the information, representations, and agreements that are the same as those that would be required to be set forth in a shareholder’s notice of nomination pursuant to Section 4, (v) in the case of a nomination by a group of shareholders, that together is an Eligible Shareholder, the designation by all group members of one member that is authorized to act on behalf of all such members with respect to the nomination and matters related thereto, including withdrawal of the nomination, (vi) the consent of each Shareholder Nominee to being named in the proxy statement as a nominee and to serving as a director if elected, (vii) representations and agreements in form and substance reasonably satisfactory to the corporation that the Eligible Shareholder: (A) acquired the Required Shares in the ordinary course of business and not with the intent to change or influence control at the corporation, and does not presently have such intent, (B) presently intends to maintain qualifying ownership of the Required Shares through the date of the annual meeting, (C) has not nominated and will not nominate for election to the board of directors at the annual meeting of shareholders any person other than the Shareholder Nominee(s) being nominated pursuant to this Section 7, (D) has not engaged and will not engage in, and has not and will not be a “participant” in another person’s “solicitation” within the meaning of Rule 14a-1(l) under the Act in support of the election of any individual as a director at the annual meeting other than its Shareholder Nominee(s) or a nominee of the board of directors and (E) agrees to comply with all applicable laws and regulations applicable to the use, if any, of soliciting material, (viii) a statement as to whether the Eligible Shareholders intend to maintain qualifying ownership of the Required Shares for at least one year following the annual meeting and (ix) an undertaking in form and substance reasonably satisfactory to the corporation that the Eligible Shareholder agrees to (A) assume all liability stemming from any legal or regulatory violation arising out of the Eligible Shareholder’s communications with the shareholders of the corporation or out of the information that the Eligible Shareholder provided to the corporation and (B) indemnify and hold harmless the corporation and each of its directors, officers and employees individually against any liability, loss, or damages in connection with any threatened or pending action, suit, or proceeding, whether legal, administrative or investigative, against the corporation or any of its directors, officers, or employees arising out of any nomination submitted by the Eligible Shareholder pursuant to this Section 7.

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(k)                                 Information to be Provided by Shareholder Nominee.  The Notice of Proxy Access Nomination must include a written representation and agreement from the Shareholder Nominee in form and substance reasonably satisfactory to the corporation that such person: (i) is not and will not become a party to (a) any agreement, arrangement or understanding with, and has not given any commitment or assurance to, any person or entity as to how such person, if elected as a director of the corporation, will act or vote on any issue or question (a “Voting Commitment”) that has not been disclosed to the corporation or (b) any Voting Commitment that could limit or interfere with such person’s ability to comply, if elected as a director of the corporation, with such person’s fiduciary duties under applicable law, (ii) in such person’s individual capacity and on behalf of any person or entity on whose behalf the nomination is being made, would be in compliance, if elected as a director of the corporation, and will comply with applicable law, all applicable rules of the U.S. exchanges upon which the common stock of the corporation is listed, and all of the corporation’s publicly disclosed corporate governance, conflict of interest, confidentiality, and stock ownership and trading policies and guidelines and (iii) will provide facts, statements and other information in all communications with the corporation and its shareholders that are or will be true and correct in all material respects and do not and will not omit to state a material fact necessary in order to make the statements made, in light of the circumstances under which they were made, not misleading. At the request of the corporation, each Shareholder Nominee for election as a director of the corporation must submit all completed and signed questionnaires required of directors and officers to the secretary of the corporation within ten (10) calendar days after such request.  The corporation may request such additional information, or such of the foregoing information in a form provided by the secretary upon written request, as necessary to permit the board of directors to determine if each Shareholder Nominee satisfies the requirements of this Section 7.

(l)                                     Notice of Defect.  In the event that any information or communications provided by the Eligible Shareholder or the Shareholder Nominee to the corporation or its shareholders ceases to be true and correct in all material respects or omits a material fact necessary to make the statements made, in light of the circumstances under which they were made, not misleading, each Eligible Shareholder or Shareholder Nominee, as the case may be, shall promptly notify the secretary of the corporation of any defect in such previously provided information and of the information that is required to correct any such defect; it being understood that providing any such notification shall not be deemed to cure any such defect or limit the remedies available to the corporation relating to any such defect.

(m)                             Exceptions Permitting Exclusion of Shareholder Nominee.  The corporation shall not be required to include in its proxy materials for any meeting of shareholders, pursuant to this Section 7, a Shareholder Nominee: (i) for which the secretary of the corporation receives a notice that a shareholder has nominated such Shareholder Nominee for election to the board of directors pursuant to the advance notice requirements for shareholder nominees for director set forth in Section 4, (ii) whose election as a member of the board of directors would cause the corporation to be in violation of the rules and listing standards of the principal U.S. exchanges upon which the common stock of the corporation is traded, or any applicable state or federal law, rule or regulation, (iii) who is an officer or director of a competitor, as defined in Section 8 of the Clayton Antitrust Act of 1914, as amended, (iv) who is a named subject of a pending criminal proceeding (excluding traffic violations and other minor

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offenses) or has been convicted in such a criminal proceeding within the past ten (10) years, (v) who is subject to any order of the type specified in Rule 506(d) of Regulation D promulgated under the Securities Act of 1933, as amended, or (vi) if such Shareholder Nominee or the applicable Eligible Shareholder has failed to comply, in all material respects, with any of its or their obligations under this Section 7 or any of its or their representations or agreements set forth in the Notice of Proxy Access Nomination (or otherwise submitted pursuant to this Section 7) or any of the information in the Notice of Proxy Access Nomination (or otherwise submitted pursuant to this Section 7) was not, when provided, true or correct in all material respects or omitted to state a material fact necessary in order to make the statements made, in light of the circumstances they were made, not misleading, or the requirements of this Section 7 have not otherwise been met.

(n)                                 Invalidity.  Notwithstanding anything to the contrary set forth herein, the board of directors shall declare a nomination by an Eligible Shareholder to be invalid, and such nomination shall be disregarded and no vote on such Shareholder Nominee will occur, notwithstanding that proxies in respect of such vote may have been received by the corporation, if: (i) the Shareholder Nominee(s) becomes ineligible or unavailable for election at the annual meeting, as determined by the board of directors, (ii) the Shareholder Nominee(s) and/or the applicable Eligible Shareholder shall have materially breached or failed to comply, in all material respects, with any of its or their obligations under this Section 7 or any of its or their representations or agreements set forth in the Notice of Proxy Access Nomination (or otherwise submitted pursuant to this Section 7) or any of the information in the Notice of Proxy Access Nomination (or otherwise submitted pursuant to this Section 7) was not, when provided, true or correct in all material respects or omitted to state a material fact necessary in order to make the statements made, in light of the circumstances they were made, not misleading, or the requirements of this Section 7 have not otherwise been met, as determined by the board of directors or the chairperson of the meeting or (iii) the Eligible Shareholder (or a qualified representative thereof) does not appear at the meeting of shareholders to present any nomination pursuant to this Section 7.  In addition, the corporation will not be required to include in its proxy materials any successor or replacement Shareholder Nominee proposed by the applicable Eligible Shareholder or any other Eligible Shareholder.

(o)                                 Interpretation.  The board of directors (and any other person or body authorized by the board of directors) shall have the power and authority to interpret this section (g) and to make any and all determinations necessary or advisable to apply this Section 7 to any persons, facts, or circumstances, including the power to determine whether: (i) a person or group of persons qualifies as an Eligible Shareholder, (ii) outstanding shares of the corporation’s capital stock are “owned” for purposes of meeting the ownership requirements of this Section 7, (iii) a notice complies with the requirements of this Section 7, (iv) a person satisfies the qualifications and requirements to be a Shareholder Nominee, (v) inclusion of the Required Information in the corporation’s proxy statement is consistent with all applicable laws, rules, regulations, and listing standards and (vii) any and all requirements of Section 3 and Section 6 have been satisfied. Any such interpretation or determination adopted in good faith by the board of directors (or any other person or body authorized by the board of directors) shall be conclusive and binding on all persons, including the corporation and all record or beneficial owners of stock of the corporation.

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Section 8.                                           Quorum.  Except as otherwise required by law, the articles of organization or these bylaws, at any meeting of shareholders, a majority of the votes entitled to be cast on a matter by a voting group shall constitute a quorum with respect to that voting group for action on that matter.  Though less than a quorum is present, any meeting may be adjourned from time to time without further notice until a quorum is secured.

Section 9.                                           Action by Vote.  With respect to each voting group, when a quorum is present as to any matter, a majority of the votes properly cast for election of a director shall effect such election, and, upon any matter other than an election of a director, votes cast favoring the matter exceeding the votes opposing the matter shall constitute favorable action on the matter, except (a) when a larger number of affirmative votes is required by law, the articles of organization or these bylaws or when the board of directors requires a larger aggregate number of affirmative votes upon such matter (to the extent permitted by law) or (b) when shareholders are selecting among several alternatives (including more nominees than directorships), in which case a plurality standard shall apply.

Section 10.                                    Voting.  Shareholders entitled to vote shall have one vote for each share of stock entitled to vote held by them of record according to the records of the corporation, unless otherwise provided by the articles of organization.

Section 11.                                    Action by Consent.  Except as otherwise required by law, any action required or permitted to be taken by the shareholders may be taken without a meeting if evidenced by consents signed by all shareholders entitled to vote on the matter.

Section 12.                                    Conduct of Meeting.  The chairperson of the board shall call to order any meeting of the shareholders of the corporation and act as chairperson of the meeting.  In the chairperson’s absence, the meeting shall be called to order (in order of priority) by a person whom the board of directors designates (who need not be an officer of the corporation), the chief executive officer of the corporation or a person chosen by the holders of a majority of the shares entitled to vote who are present, in person or by proxy.  If the secretary of the corporation is absent from the meeting, the secretary of the meeting shall be the person the chairperson appoints.  The chairperson of any meeting of shareholders of the corporation shall determine the order of business and the rules of procedure for the conduct of such meeting, including the manner of voting and the conduct of discussion.  The chairperson shall have the power to adjourn the meeting to another place, if any, date and time.

Section 13.                                    Remote Participation.  Subject to such guidelines and procedures as the board of directors may adopt, at any meeting of shareholders, the board of directors may permit shareholders and proxyholders not physically present at the meeting to participate in the meeting, be deemed present in person, and vote at the meeting, by means of remote communications subject to such guidelines and procedures as the board of directors may adopt.  Such guidelines and procedures shall include reasonable measures to (1) verify that each person deemed present and permitted to vote at the meeting by means of remote communication is a shareholder or proxyholder, and (2) provide such shareholders and proxyholders a reasonable opportunity to participate in the meeting and to vote on matters submitted to the shareholders, including an opportunity to read or hear the proceedings of the meeting substantially concurrently with such proceedings.  If any shareholder or proxyholder votes or takes other action at the meeting by

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means of remote communication, a record of such vote or other action shall be maintained by the corporation.

ARTICLE II

Directors and Officers

Section 1.                                           Enumeration.  The corporation shall have a board of directors consisting of not less than three directors, except that whenever there shall be fewer than three shareholders, the number of directors may be less than three but in no event less than the number of shareholders.  The size of the board of directors shall be fixed by the board of directors and may be increased or decreased at any time by vote of a majority of the directors then in office, subject to the articles of organization.  The officers of the corporation shall be a president, a treasurer, a secretary, such other officers as the board of directors may from time to time appoint.

Section 2.                                           Qualifications.  Directors and officers need not be shareholders.  Two or more offices may be held by the same person.

Section 3.                                           Election.  The directors shall be elected in the manner provided in the articles of organization and these bylaws.  Officers shall be appointed by the board of directors.

Section 4.                                           Removal.  Directors may be removed from office only as provided in the articles of organization.  Officers may be removed from their respective offices with or without cause by the board of directors or the chief executive officer, if any, or the president, if there is no chief executive officer.

Section 5.                                           Resignation.  Resignations by directors shall be given in writing or by electronic transmission to the board of directors, the chairperson of the board or the secretary.  Resignations by officers shall be given in writing or by electronic transmission to the corporation.  Each such resignation shall be effective upon receipt unless specified to be effective at some other time acceptable to the corporation.

ARTICLE III

Meeting of the Directors

Section 1.                                           Regular Meetings.  Regular meetings of the board of directors may be held at such times and places as the board of directors may fix.

Section 2.                                           Special Meetings.  Special meetings of the board of directors may be held at any time and at any place designated in the notice of the meeting, when called by the chairperson of the board, if any, the chief executive officer (or, if there is no chief executive officer, the president), the secretary or by two or more directors.

Section 3.                                           Notice.  Twenty-four hours notice shall be given for a meeting of the board of directors unless waived.  A notice or waiver of notice need not specify the purpose of the meeting.  Notice of a meeting need not be given to any director if a waiver of notice, signed by the director before or after the meeting, or delivered by the director by means of electronic

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transmission, is filed with the minutes or to any director who attends the meeting without objecting to holding the meeting or transacting business at the meeting at the beginning of the meeting or promptly upon the director’s arrival or who thereafter votes for or assents to action taken at the meeting.

Section 4.                                           Quorum.  A majority of the directors then in office shall constitute a quorum, but a smaller number may make a determination pursuant to Section 8.53 or Section 8.55 of chapter 156D of the Massachusetts General Laws that indemnification is permissible in a specific proceeding.  In addition, though less than a quorum is present, the chairperson of the board, if any, or a majority of the votes cast on the question may adjourn a meeting finally or from time to time without further notice until a quorum is secured.  If a quorum is present, a majority of the directors present may take any action that the board of directors is required or permitted to take unless a different number is required by law, the articles of organization or these bylaws.

Section 5.                                           Action by Consent.  Any action required or permitted to be taken at any meeting of the board of directors may be taken without a meeting if all the directors consent to the action in writing or by means of electronic transmission and the consents are filed with the records of the meetings of board of directors.  Such consents shall be treated for all purposes as votes at a meeting.

Section 6.                                           Committees.  The board of directors may create committees of the board of directors and may delegate to such committees some or all of the powers of the board of directors to the extent permitted by law.  Except as the board of directors may otherwise determine, any such committee may make rules for the conduct of its business, but unless otherwise provided by the board of directors or in such rules, its business shall be conducted as nearly as practical in the same manner as is provided by these bylaws for the board of directors.  The board of directors shall have the power at any time to fill vacancies in any such committee, to change its membership or to discharge the committee.

ARTICLE IV

Powers and Duties of Directors and Officers

Section 1.                                           Directors.  The business and affairs of the corporation shall be managed under the direction of the board of directors, which may exercise all powers of the corporation that are not by law, the articles of organization or these bylaws required to be otherwise exercised.  The board of directors may from time to time, to the extent permitted by law, delegate any of its powers to committees, officers, attorneys or agents of the corporation, subject to such limitations as the board of directors may impose.

Section 2.                                           Chairperson and President.  The board of directors may appoint a chairperson of the board who, unless otherwise determined by the board of directors, shall preside, when present, at meetings of the board of directors and shall have such other powers and duties as customarily belong to the office of chairperson of the board or as may be designated from time to time by the board of directors.  The president shall be the chief executive officer of the corporation, unless the board of directors designates another officer.  The chief executive

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officer shall, subject to the direction of the board of directors, have general supervision and control of the business of the corporation.  In the absence of the chairperson of the board and unless the board of directors specifies otherwise, the chief executive officer shall preside at all meetings of shareholders and of the board of directors at which the chief executive officer is present.  The president and the chief executive officer shall perform such other duties and shall have such other powers as the board of directors may designate from time to time.

Section 3.                                           Treasurer.  Except as the board of directors shall otherwise determine, the treasurer shall be the chief financial officer of the corporation and shall have such powers and duties as customarily belong to the office of treasurer or as may be designated from time to time by the board of directors or by the president.

Section 4.                                           Secretary.  The secretary and any assistant secretaries shall have responsibility for preparing, or overseeing the preparation of, minutes of meetings of the shareholders and board of directors and for authenticating, or overseeing the authentication of, records of the corporation.

Section 5.                                           Other Officers.  Other officers of the corporation, if any, shall have such powers, duties and titles as may be designated from time to time by the board of directors or by the president.

Section 6.                                           Equity Awards.  The board of directors may delegate to the chief executive officer, the president or a vice president authority to grant options or other equity incentive awards provided (a) such awards are pursuant to an equity incentive plan approved by the board of directors or a committee of the board of directors and (b) the grants satisfy parameters established under such equity incentive plan or otherwise set by the board of directors or a committee of the board of directors.  The consideration received by the corporation in connection with shares issued pursuant to such awards shall be deemed adequate.

ARTICLE V

Employment Contracts

The corporation may enter into employment contracts authorized by the board of directors extending beyond the terms of the directors.  An employment contract shall be valid despite any inconsistent provision of these bylaws relating to terms of officers and removal of officers with or without cause but shall not affect the authority of the board of directors to remove officers.  Any removal or failure to reappoint an officer shall be without prejudice to the officer’s contract rights, if any.

ARTICLE VI

Stock and Transfer Books

The corporation or its agent shall maintain a record of its shareholders, in a form that permits preparation of a list of names and addresses of all shareholders, in alphabetical order by class of shares showing the number and class of shares held by each.  The corporation for all purposes may conclusively presume that the registered holder of a stock certificate is the

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absolute owner of the shares represented thereby and that the shareholder’s record address is the shareholder’s correct address.

ARTICLE VII

Share Certificates

The board of directors may authorize the issuance without certificates of some or all of the shares of any or all of the corporation’s classes or series of stock.  Except to the extent the board of directors has determined to issue shares without certificates, a shareholder shall be entitled to a certificate stating the number, the class and the designation of the series, if any, of the shares the certificate represents, in such form as shall, in conformity with law, be prescribed from time to time by the board of directors.  Such certificate shall be signed by any two of the chief executive officer, the president, a vice president, the treasurer, an assistant treasurer, the secretary or an assistant secretary.  Such signatures may be facsimiles.  If the person who signed, either manually or in facsimile, a share certificate no longer holds office when the certificate is issued, the certificate shall be nevertheless valid.

ARTICLE VIII

Fiscal Year

The fiscal year shall be fixed from time to time by the board of directors.

ARTICLE IX

Massachusetts Control Share Acquisition Act

The provisions of Chapter 110D of the Massachusetts General Laws shall not apply to the corporation.

ARTICLE X

Amendment of Bylaws

These bylaws may be amended, altered or repealed in whole or in part, and new bylaws may be adopted, by the shareholders, in each case, by votes cast in favor of such action representing a majority of the votes entitled to be cast on the matter.  The board of directors may also make, amend or repeal these bylaws in whole or in part, except with respect to any provision that by law, the articles of organization or these bylaws requires action by the shareholders.  Not later than the time of giving notice of the meeting of shareholders next following the making, amending or repealing by the board of directors of any bylaw, notice thereof stating the substance of the action taken by the board of directors shall be given to all shareholders entitled to vote on amending the bylaws.

Adopted by the board of directors March 7, 2019
Approved by the shareholders March 7, 2019

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Exhibit 4.3

CYCLERION THERAPEUTICS, INC.

2019 EMPLOYEE STOCK PURCHASE PLAN

1.                                      Defined Terms

Exhibit A, which is incorporated by reference, defines the terms used in the Plan and sets forth certain operational rules related to those terms.

2.                                      Purpose of Plan

The Plan is intended to enable Eligible Employees to use payroll deductions to purchase shares of Stock in offerings under the Plan, and thereby acquire an interest in the future of the Company.  The Plan is intended to qualify as an “employee stock purchase plan” under Section 423 of the Code and to be exempt from the application and requirements of Section 409A of the Code, and is to be construed accordingly.

3.                                      Options to Purchase Stock

Subject to adjustment pursuant to Section 16 of the Plan, the maximum aggregate number of shares of Stock available for purchase under the Plan to Eligible Employees will be 400,000 shares, plus an annual increase to be added on the date of each specified annual meeting of the stockholders of the Company, beginning with the first annual meeting of stockholders following the Effective Date and ending with the ninth annual meeting of stockholders following the Effective Date, equal to the lesser of (i) one percent (1%) of the number of shares of Stock outstanding on a fully diluted basis as of the close of business on the immediately preceding day (calculated by adding to the number of shares of Stock outstanding, all outstanding securities convertible into Stock on such date on an as converted basis), and (ii) an amount determined by the Administrator on or prior to the date of such annual meeting of stockholders.  The shares of Stock to be delivered upon exercise of Options under the Plan may be either shares of authorized but unissued Stock, treasury Stock or previously issued Stock acquired by the Company.  If any Option granted under the Plan expires or terminates for any reason without having been exercised in full or ceases for any reason to be exercisable in whole or in part, the unpurchased shares of Stock subject to such Option will again be available for purchase under the Plan.  If, on an Exercise Date, the total number of shares of Stock that would otherwise be subject to Options granted under the Plan exceeds the number of shares then available under the Plan (after deduction of all shares for which Options have been exercised or are then outstanding), the Administrator shall make a pro rata allocation of the shares remaining available for purchase under the Plan in as uniform a manner as shall be practicable and as it shall determine to be equitable.  In such event, the Administrator shall notify each Participant of such reduction and of the effect on the Participant’s Options and may reduce the rate of payroll deductions, if necessary.

4.                                      Eligibility

(a)                                 Eligibility Requirements.  Subject to Section 13 of the Plan, and the exceptions and limitations set forth in Sections 4(b), 4(c) and 6 of the Plan, or as may be provided elsewhere in the Plan, each Employee (i) who has been continuously employed by the Company or a

Designated Subsidiary, as applicable, for a period of at least fifteen (15) Business Days as of the first day of an Option Period, (ii) whose customary Employment with the Company or a Designated Subsidiary, as applicable, is for more than five (5) months per calendar year, (iii) who customarily works twenty (20) hours or more per week, and (iv) who satisfies the requirements set forth in the Plan will be an Eligible Employee.

(b)                                 Five Percent Shareholders.  No Employee may be granted an Option under the Plan if, immediately after the Option is granted, the Employee would own (or pursuant to Section 424(d) of the Code would be deemed to own) stock possessing five percent (5%) or more of the total combined voting power or value of all classes of stock of the Company or of its Parent or Subsidiaries, if any.

(c)                                  Additional Requirements.  The Administrator may, for Option Periods that have not yet commenced, establish additional or different eligibility requirements not inconsistent with Section 423 of the Code.

5.                                      Option Periods

The Plan will generally be implemented by a series of separate offerings referred to as “Option Periods”.  Unless otherwise determined by the Administrator, the Option Periods will be successive periods of approximately six (6) months commencing on the first Business Day in June and December of each year, anticipated to be on or around June 1 and December 1, and ending approximately six (6) months later on the last Business Day in November or May, as applicable, of each year, anticipated to be on or around November 30 and May 31.  The last Business Day of each Option Period will be an “Exercise Date”.  The Administrator may change the Exercise Date, the commencement date, the ending date and the duration of each Option Period to the extent permitted by Section 423 of the Code; provided, however, that no Option may be exercised after 27 months from its grant date.

6.                                      Option Grant

Subject to the limitations set forth in Sections 4 and 10 of the Plan and the Maximum Share Limit, on the first day of an Option Period, each Participant automatically will be granted an Option to purchase shares of Stock on the Exercise Date; provided, however, that no Participant will be granted an Option under the Plan that permits the Participant’s right to purchase shares of Stock under the Plan and under all other employee stock purchase plans of the Company and its Parent and Subsidiaries, if any, to accrue at a rate that exceeds $25,000 in Fair Market Value (or such other maximum as may be prescribed from time to time by the Code) for each calendar year during which any Option granted to such Participant is outstanding at any time, as determined in accordance with Section 423(b)(8) of the Code.

7.                                      Method of Participation

(a)                                 Payroll Deduction and Participation Authorization.  To participate in an Option Period, an Eligible Employee must execute and deliver to the Administrator a payroll deduction and participation authorization form in accordance with the procedures prescribed by, and in a form acceptable to, the Administrator and, in so doing, the Eligible Employee will thereby become a Participant as of the first day of such Option Period.  Such an Eligible Employee will

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remain a Participant with respect to subsequent Option Periods until his or her participation in the Plan is terminated as provided herein.  Such payroll deduction and participation authorization must be delivered not later than fifteen (15) Business Days prior to the first day of an Option Period, or such other time as specified by the Administrator.

(b)                                 Changes to Payroll Deduction Authorization for Subsequent Option Periods.  A Participant’s payroll deduction authorization will remain in effect for subsequent Option Periods unless the Participant files a new authorization not later than fifteen (15) Business Days prior to the first day of the subsequent Option Period (or such other time as specified by the Administrator) or the Participant’s Option is cancelled pursuant to Section 13 or 14 of the Plan.

(c)                                  Changes to Payroll Deduction Authorization for Current Option Period.  During an Option Period, a Participant may decrease his or her payroll deduction authorization once, but may not increase his or her payroll deduction authorization.  Any election to decrease to a Participant’s payroll deduction authorization intended to be effective for the Option Period during which the election to decrease is made must be delivered to the Administrator in accordance with the procedures prescribed by, and in a form acceptable to, the Administrator and will be effective as soon as administratively practicable.  If a Participant’s payroll deduction authorization is reduced to 0% during an Option Period, payroll deductions previously accumulated during such Option Period will be applied to purchase shares of Stock on the Exercise Date for that Option Period and the Participant’s participation in the Plan will thereupon terminate, unless the Participant has delivered a new payroll deduction authorization for the subsequent Option Period in accordance with the rules of Section 7(b) above.  A Participant may also terminate his or her payroll deduction authorization during an Option Period by canceling his or her Option in accordance with Section 13 of the Plan.

(d)                                 Payroll Deduction Percentage.  Each payroll deduction authorization will authorize payroll deductions as a whole percentage from one percent (1%) to fifteen percent (15%) of the employee’s Eligible Compensation per payroll period.

(e)                                  Payroll Deduction Account.  All payroll deductions made pursuant to this Section 7 will be credited to the Participant’s Account.  Amounts credited to a Participant’s Account will not be required to be set aside in trust or otherwise segregated from the Company’s general assets.

8.                                      Method of Payment

A Participant must pay for shares of Stock purchased under the Plan with accumulated payroll deductions credited to the Participant’s Account, unless otherwise provided by the Administrator under a sub-plan or separate offering for a non-U.S. Designated Subsidiary.

9.                                      Purchase Price

The Purchase Price of shares of Stock issued pursuant to the exercise of an Option on each Exercise Date will be eighty-five percent (85%) (or such greater percentage specified by the Administrator to the extent permitted under Section 423 of the Code) of the lesser of (a) the Fair Market Value of a share of Stock on the date on which the Option was granted pursuant to Section 6 of the Plan (i.e., the first day of the Option Period) and (b) the Fair Market Value of a

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share of Stock on the date on which the Option is deemed exercised pursuant to Section 10 of the Plan (i.e., the Exercise Date).

10.                               Exercise of Options

(a)                                 Purchase of Shares.  Subject to the limitations set forth in Section 6 of the Plan and this Section 10, with respect to each Option Period, on the applicable Exercise Date, each Participant will be deemed to have exercised his or her Option and the accumulated payroll deductions in the Participant’s Account will be applied to purchase the greatest number of shares of Stock (rounded down to the nearest whole share) that can be purchased with such Account balance at the applicable Purchase Price; provided, however, that no more than 2,500 shares of Stock may be purchased by a Participant on any Exercise Date, or such lesser number as the Administrator may prescribe in accordance with Section 423 of the Code (the “Maximum Share Limit”).  As soon as practicable thereafter, shares of Stock so purchased will be placed, in book-entry form, into a record keeping account in the name of the Participant.  No fractional shares will be purchased pursuant to the exercise of an Option under the Plan; any accumulated payroll deductions in a Participant’s Account that are not sufficient to purchase a whole share will be retained in the Participant’s Account for the subsequent Option Period, subject to earlier withdrawal by the Participant as provided in Section 13 hereof.

(b)                                 Return of Account Balance.  Except as provided in Section 10(a) with respect to fractional shares, any amount of payroll deductions in a Participant’s Account that are not used for the purchase of shares of Stock, whether because of the Participant’s withdrawal from participation in an Option Period or for any other reason, will be returned to the Participant (or his or her designated beneficiary or legal representative, as applicable), without interest, as soon as administratively practicable after such withdrawal or other event, as applicable.  If the Participant’s accumulated payroll deductions on the Exercise Date of an Option Period would otherwise enable the Participant to purchase shares of Stock in excess of the Maximum Share Limit or the maximum number of shares of Stock that may be purchased by a Participant pursuant to Section 6 of the Plan, the excess of the amount of the accumulated payroll deductions over the aggregate Purchase Price of the shares of Stock actually purchased will be returned to the Participant, without interest, as soon as administratively practicable after such Exercise Date.

11.                               Interest

No interest will be payable on any amount held in the Account of any Participant.

12.                               Taxes

Payroll deductions will be made on an after-tax basis.  The Administrator will have the right to make such provision as it deems necessary for, and may condition the exercise of an Option on, the satisfaction of its obligations to withhold federal, state, local income or other taxes incurred by reason of the purchase or disposition of shares of Stock under the Plan.  In the Administrator’s discretion and subject to applicable law, such tax obligations may be paid in whole or in part by delivery of shares of Stock to the Company, including shares of Stock purchased under the Plan, valued at Fair Market Value, but not in excess of the minimum statutory amounts required to be withheld.

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13.                               Cancellation and Withdrawal

(a)                                 Cancellation of Payroll Deduction Authorization and Withdrawal from Plan.  A Participant who holds an Option under the Plan may cancel all (but not less than all) of his or her Option and terminate his or her payroll deduction authorization by notice delivered to the Administrator in accordance with the procedures prescribed by, and in a form acceptable to, the Administrator.  To be effective with respect to an upcoming Exercise Date, such cancellation notice must be delivered not later than fifteen (15) Business Days prior to such Exercise Date (or such other time as specified by the Administrator).  Upon such termination and cancellation, the balance in the Participant’s Account will be returned to the Participant, without interest, as soon as administratively practicable thereafter.  For the avoidance of doubt, a Participant who reduces his or her withholding rate for a future Option Period or future payroll periods within an ongoing Option period to 0% pursuant to Section 7 of the Plan, will be deemed to have terminated his or her payroll deduction authorization and canceled his or her participation in future Option Periods, unless the Participant delivers a new payroll deduction authorization for a subsequent Option Period in accordance with the rules of Section 7(b) of the Plan.

(b)                                 401(k) Hardship Withdrawal.  To the extent required by applicable law, a Participant who makes a hardship withdrawal from a 401(k) Plan will be deemed to have terminated his or her payroll deduction authorization for subsequent payroll dates relating to the then current Option Period as of the date of such hardship withdrawal and amounts accumulated in the Participant’s Account as of such date will be returned to the Participant, without interest, as soon as administratively practicable thereafter.  To the extent required by applicable law, an Employee who has made a hardship withdrawal from a 401(k) Plan will not be permitted to participate in Option Periods commencing after the date of his or her hardship withdrawal until the first Option Period that begins at least six months after the date of his or her hardship withdrawal.

14.                               Termination of Employment; Death of Participant

Upon the termination of a Participant’s employment with the Company or a Designated Subsidiary, as applicable, for any reason (including the death of a Participant during an Option Period prior to an Exercise Date) or in the event the Participant ceases to qualify as an Eligible Employee, the Participant will cease to be a Participant, any Option held by the Participant under the Plan will be canceled, the balance in the Participant’s Account will be returned to the Participant (or his or her estate or designated beneficiary in the event of the Participant’s death), without interest, as soon as administratively practicable thereafter, and the Participant will have no further rights under the Plan.

15.                               Equal Rights; Participant’s Rights Not Transferable

All Participants granted Options in an offering under the Plan will have the same rights and privileges, consistent with the requirements set forth in Section 423 of the Code.  Any Option granted under the Plan will be exercisable during the Participant’s lifetime only by him or her and may not be sold, pledged, assigned, or transferred in any manner.  In the event any Participant violates or attempts to violate the terms of this Section 15, as determined by the Administrator in its sole discretion, any Options held by the Participant under the Plan may be

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terminated by the Company and, upon the return to the Participant of the balance of his or her Account, without interest, all of the Participant’s rights under the Plan will terminate.

16.                               Change in Capitalization; Corporate Transaction

(a)                                 Change in Capitalization.  In the event of any change in the outstanding Stock by reason of a stock dividend, stock split, reverse stock split, split-up, recapitalization, merger, consolidation, reorganization, or other capital change, the aggregate number and type of shares of Stock available under the Plan, the number and type of shares of Stock granted under any outstanding Options, the Maximum Share Limit and the purchase price per share of Stock under any outstanding Option will be appropriately adjusted; provided, that any such adjustment shall be made in a manner that complies with Section 423 of the Code.

(b)                                 Corporate Transaction.  In the event of a sale of all or substantially all of the Stock or a sale of all or substantially all of the assets of the Company, or a merger or similar transaction in which the Company is not the surviving corporation or that results in the acquisition of the Company by another person, the Administrator may, in its discretion, (i) if the Company is merged with or acquired by another corporation, provide that each outstanding Option will be assumed or exchanged for a substitute Option granted by the acquiror or successor corporation or by a parent or subsidiary of the acquiror or successor corporation, (ii) cancel each outstanding Option and return the balances in Participants’ Accounts to the Participants, without interest, and/or (iii) pursuant to Section 18 of the Plan, terminate the Option Period on or before the date of the proposed sale, merger or similar transaction.

17.                               Administration of Plan

The Plan will be administered by the Administrator, which will have the authority to interpret the Plan, determine eligibility under the Plan, prescribe forms, rules and procedures relating to the Plan and otherwise do all things necessary or appropriate to carry out the purposes of the Plan.  All determinations and decisions by the Administrator regarding the interpretation or application of the Plan will be final and binding on all Participants and all persons.

The Administrator may specify the manner in which the Company and/or Employees are to provide notices and forms under the Plan, and may require that such notices and forms be submitted electronically.

18.                               Amendment and Termination of Plan; Separate Offerings; Sub-Plans

(a)                                 Amendment.  The Board reserves the right at any time or times to amend the Plan to any extent and in any manner it may deem advisable; provided, however, that any amendment that would be treated as the adoption of a new plan for purposes of Section 423 of the Code will have no force or effect unless approved by the shareholders of the Company within 12 months before or after its adoption.

(b)                                 Termination.  The Board reserves the right at any time or times to suspend or terminate the Plan.  In connection therewith, the Board may provide, in its sole discretion, either that outstanding Options will be exercisable either on the Exercise Date for the applicable Option Period or on such earlier date as the Board may specify (in which case such earlier date will be

6

treated as the Exercise Date for the applicable Option Period), or that the balance of each Participant’s Account will be returned to the Participant, without interest.

(c)                                  Separate Offerings; Sub-Plans.  Notwithstanding the foregoing or any provision of this Plan to the contrary, consistent with the requirements of Section 423 of the Code, the Administrator may, in its sole discretion, amend the terms of the Plan, or an offering, and/or provide for separate offerings under this Plan in order to, among other things, reflect the impact of local law outside of the United States as applied to one or more Eligible Employees of a Designated Subsidiary and may, where appropriate, establish one or more sub-plans to reflect such amended provisions.

19.                               Approvals

Shareholder approval of the Plan will be obtained prior to the date that is twelve (12) months after the date of Board approval.  In the event that the Plan has not been approved by the shareholders of the Company prior to the first anniversary of the Effective Date, all Options to purchase shares of Stock under the Plan will be cancelled and become null and void.

Notwithstanding anything herein to the contrary, the obligation of the Company to issue and deliver shares of Stock under the Plan will be subject to the approval required of any governmental authority in connection with the authorization, issuance, sale or transfer of such shares of Stock and to any requirements of any national securities exchange applicable thereto, and to compliance by the Company with other applicable legal requirements in effect from time to time.

20.                               Participants’ Rights as Shareholders and Employees

A Participant will have no rights or privileges as a shareholder of the Company and will not receive any dividends in respect of any shares of Stock covered by an Option granted hereunder until such Option has been exercised, full payment has been made for such shares, and the shares have been issued to the Participant.

Nothing contained in the provisions of the Plan will be construed as giving to any Employee the right to be retained in the employ of the Company or any Designated Subsidiary or as interfering with the right of the Company or any Designated Subsidiary to discharge, promote, demote or otherwise re-assign any Employee from one position to another within the Company or any Designated Subsidiary at any time.

21.                               Limitations on Dispositions; Information Regarding Disqualifying Dispositions.

Shares of Stock purchased under the Plan may, as determined by the Administrator in its sole discretion, be subject to a holding period during which such shares may not be sold, transferred, withdrawn, or moved.

By electing to participate in the Plan, each Participant agrees to provide such information about any transfer of Stock acquired under the Plan that occurs within two years after the first day of the Option Period in which such Stock was acquired and within one year after the day

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such Stock was purchased as may be requested by the Company or any Designated Subsidiary in order to assist it in complying with applicable tax laws.

22.                               Governing Law

The Plan will be governed by and administered in accordance with the laws of the Commonwealth of Massachusetts, and with the applicable requirements of the stock exchanges or other trading systems on which the Stock is listed or entered for trading and the Code, in each case as determined by the Administrator.  Except as otherwise provided under a sub-plan described in Section 18(c) of the Plan or as provided in the first sentence of this Section 22, the domestic substantive laws of Massachusetts govern the provisions of the Plan or any Options under the Plan or relating to the subject matter hereof or thereof without giving effect to any choice or conflict of laws provision or rule that would cause the application of the domestic substantive laws of any other jurisdiction.

23.                               Effective Date and Term

The Effective Date of the Plan will be the date of adoption of the Plan by the Board.  No rights will be granted hereunder after the earliest to occur of (a) the Plan’s termination by the Company, (b) the issuance of all shares of Stock available for issuance under the Plan or (c) the day before the 10-year anniversary of the date the Board approves the Plan.

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EXHIBIT A

Definition of Terms

The following terms, when used in the Plan, will have the meanings and be subject to the provisions set forth below:

“401(k) Plan”:  A savings plan qualifying under Section 401(k) of the Code that is sponsored by the Company or one of its Subsidiaries for the benefit of its employees.

“Account”:  A payroll deduction account maintained in the Participant’s name on the books of the Company.

“Administrator”:  The Compensation Committee of the Board, except that the Compensation Committee may delegate (i) to one or more members one or more of its members (or one or more other members of the Board, including the full Board) such of its duties, powers and responsibilities as it may determine and (ii) to such Employees or other persons as it determines such ministerial tasks as it deems appropriate.  In the event of any delegation described in the preceding sentence, the term “Administrator” will include the person or persons so delegated to the extent of such delegation.

“Board”:  The Board of Directors of the Company.

“Business Day”:  Any day on which the established national exchange or trading system (including the Nasdaq Stock Market) on which the Stock is traded is available and open for trading.

“Code”:  The U.S. Internal Revenue Code of 1986, as from time to time amended and in effect, or any successor statute as from time to time in effect.

“Company”:  Cyclerion Therapeutics, Inc., a Massachusetts corporation.

“Designated Subsidiary”:  A Subsidiary of the Company that has been designated by the Board or the Compensation Committee of the Board from time to time as eligible to participate in the Plan as set forth on Exhibit B to the Plan.  For the avoidance of doubt, any Subsidiary of the Company shall be eligible to be designated as a Designated Subsidiary hereunder.

“Effective Date”:  The date set forth in Section 23 of the Plan.

“Eligible Compensation”:  Compensation, as such term is defined in the Cyclerion Therapeutics, Inc. 401(k) Plan.

“Eligible Employee”:  Any Employee who meets the eligibility requirements set forth in Section 4 of the Plan.

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“Employee”:  Any person who is employed by the Company or a Designated Subsidiary.  For the avoidance of doubt, independent contractors and consultants are not “Employees”.

“Exercise Date”:  The date set forth in Section 5 of the Plan or otherwise designated by the Administrator with respect to a particular Option Period on which a Participant will be deemed to have exercised the Option granted to him or her for such Option Period.

“Fair Market Value”:  As of a particular date, (i) the closing price for a share of Stock reported on the Nasdaq Stock Market (or any other national securities exchange on which the shares are then listed) for that date or, if no closing price is reported for that date, the closing price on the immediately preceding date on which a closing price was reported or (ii) in the event that the Stock is not traded on a national securities exchange, the fair market value of a share of Stock determined by the Administrator consistent with the rules of Section 422 of the Code and Section 409A of the Code to the extent applicable.

“Maximum Share Limit”:  The meaning set forth in Section 10 of the Plan.

“Option”:  An option granted pursuant to the Plan entitling the holder to acquire shares of Stock upon payment of the Purchase Price per share of Stock.

“Option Period”:  An offering period established in accordance with Section 5 of the Plan.

“Parent”:  A “parent corporation” as defined in Section 424(e) of the Code.

“Participant”:  An Eligible Employee who elects to enroll in the Plan.

“Plan”:  The Cyclerion Therapeutics, Inc. 2019 Employee Stock Purchase Plan, as from time to time amended and in effect.

“Purchase Price”:  The price per share of Stock with respect to an Option Period determined in accordance with Section 9 of the Plan.

“Stock”:  Common stock of the Company, par value $0.00 per share.

“Subsidiary”:  A “subsidiary corporation” as defined in Section 424(f) of the Code.

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EXHIBIT B

Designated Subsidiaries

Designated Subsidiaries as of the date of adoption of the Plan by the Board are listed below:

N/A

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Exhibit 4.4

CYCLERION THERAPEUTICS, INC.
2019 EQUITY INCENTIVE PLAN

1.                                      DEFINED TERMS

Exhibit A, which is incorporated by reference, defines the terms used in the Plan and includes certain operational rules related to those terms.

2.                                      PURPOSE

The Plan has been established to advance the interests of the Company by providing for the grant to Participants of Stock, Stock-based and other incentive Awards.

3.                                      ADMINISTRATION

The Administrator has discretionary authority, subject only to the express provisions of the Plan, to interpret the Plan; determine eligibility for and grant Awards; determine, modify or waive the terms and conditions of any Award; determine the form of settlement of Awards (whether in cash, shares of Stock, or other property); prescribe forms, rules and procedures relating to the Plan and Awards; and otherwise do all things necessary or desirable to carry out the purposes of the Plan.  Determinations of the Administrator made under the Plan are conclusive and bind all persons.

4.                                      LIMITS ON AWARDS UNDER THE PLAN

(a)                                 Number of Shares.  Subject to adjustment as provided in Section 7(b), the maximum number of shares of Stock that may be issued in satisfaction of Awards under the Plan is 2,500,000 shares, plus (1) an annual increase to be added on the date of each annual meeting of the stockholders of the Company, beginning with the first annual meeting of stockholders following the Date of Adoption and ending with the ninth annual meeting of stockholders following the Date of Adoption, equal to the lesser of (i) four percent (4%) of the number of shares of Stock outstanding on a fully diluted basis as of the close of business on the immediately preceding business day (calculated by adding to the number of shares of Stock outstanding, all outstanding securities convertible into Stock on such date on an as converted basis) and (ii) an amount determined by the Administrator on or prior to the date of such annual meeting of stockholders and (2) any shares of Stock underlying awards granted under the Company’s Amended and Restated 2005 Stock Incentive Plan or the Company’s Amended and Restated 2010 Employee, Director and Consultant Equity Incentive Plan that are forfeited, expired or are cancelled without the delivery of shares of Stock thereunder.  Up to the total number of shares of Stock set forth in the preceding sentence may be issued in satisfaction of ISOs, but nothing in this Section 4(a) will be construed as requiring that any, or any fixed number of, ISOs be awarded under the Plan.  For purposes of this Section 4(a), the number of shares of Stock issued in satisfaction of Awards will be determined by excluding (i) shares of Stock withheld by the Company in payment of the exercise price or purchase price of the Award or in satisfaction of tax withholding requirements with respect to the Award, (ii) the full number of shares covered by a SAR any portion of which is settled in Stock (and not only the number of shares of Stock delivered in settlement), and (iii) any shares of Stock underlying Awards settled in cash or that expire, become unexercisable, terminate or are forfeited to or repurchased by the Company without the issuance of Stock.  For

the avoidance of doubt, the number of shares of Stock available for delivery under the Plan will not be increased by any shares of Stock delivered under the Plan that are subsequently repurchased using proceeds directly attributable to Stock Option exercises.  The limits set forth in this Section 4(a) will be construed to comply with Section 422.

(b)                                 Substitute Awards.  The Administrator may grant Substitute Awards under the Plan.  To the extent consistent with the requirements of Section 422 and the regulations thereunder and other applicable legal requirements (including applicable stock exchange requirements), Stock issued under Substitute Awards will be in addition to and will not reduce the number of shares available for Awards under the Plan set forth in Section 4(a), but, notwithstanding anything in Section 4(a) to the contrary, if any Substitute Award is settled in cash or expires, becomes unexercisable, terminates or is forfeited to or repurchased by the Company without the issuance of Stock, the shares of Stock previously subject to such Award will not be available for future grants under the Plan.  The Administrator will determine the extent to which the terms and conditions of the Plan apply to Substitute Awards, if at all, provided, however, that Substitute Awards will not be subject to the per-Participant Award limits described in Section 4(d) below.

(c)                                  Type of Shares.  Stock delivered by the Company under the Plan may be authorized but unissued Stock, treasury Stock or previously issued Stock acquired by the Company.  No fractional shares of Stock will be delivered under the Plan.

(d)                                 Individual Limit.

(1)                                 Awards comprising no more than 1,000,000 shares of Stock may be granted to any person under the Plan in any calendar year.  In applying the foregoing limit, (i) all Awards granted to the same person in the same calendar year are aggregated and made subject to one limit; (ii) the limit as applicable to Stock Options and SARs refers to the number of shares of Stock underlying those Awards; and (iii) the share limit as applicable to Awards other than Stock Options and SARs refers to the maximum number of shares of Stock that may be delivered, or the value of which could be paid in cash or other property, under an Award or Awards assuming a maximum payout.

(2)                                 Notwithstanding the foregoing limit, the aggregate value of all compensation granted or paid to any Director with respect to any calendar year, including Awards granted under the Plan and cash fees or other compensation paid by the Company to such Director outside of the Plan for his or her services as a Director during such calendar year, may not exceed $400,000 in the aggregate, calculating the value of any Awards based on the grant date fair value in accordance with the Accounting Rules, assuming a maximum payout.  To the extent applicable, the foregoing provisions will be construed in a manner consistent with Section 162(m), including, without limitation, where applicable, the rules under Section 162(m) pertaining to permissible deferrals of exempt awards.

5.                                      ELIGIBILITY AND PARTICIPATION

The Administrator shall select Participants from among key Employees and Directors of, and consultants and advisors to, the Company and its subsidiaries.  Eligibility for ISOs is limited

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to individuals described in the first sentence of this Section 5 who are employees of the Company or of a “parent corporation” or “subsidiary corporation” of the Company as those terms are defined in Section 424 of the Code.  Eligibility for Stock Options, other than ISOs, and SARs is limited to individuals described in the first sentence of this Section 5 who are providing direct services on the date of grant of the Award to the Company or to a subsidiary of the Company that would be described in the first sentence of Treas. Regs. §1.409A-1(b)(5)(iii)(E).

6.                                      RULES APPLICABLE TO AWARDS

(a)                                 All Awards.

(1)                                 Award Provisions.  The Administrator shall determine the terms of all Awards, subject to the limitations provided herein.  By accepting (or, under such rules as the Administrator may prescribe, being deemed to have accepted) an Award, the Participant will be deemed to have agreed to the terms of the Award and the Plan.  Notwithstanding any provision of this Plan to the contrary, Substitute Awards may contain terms and conditions that are inconsistent with the terms and conditions specified herein, as determined by the Administrator.

(2)                                 Term of Plan.  No Awards may be made after 10 years from the Date of Adoption, but previously granted Awards may continue beyond that date in accordance with their terms.

(3)                                 Transferability.  Neither ISOs nor, except as the Administrator otherwise expressly provides in accordance with the third sentence of this Section 6(a)(3), other Awards may be transferred other than by will or by the laws of descent and distribution.  During a Participant’s lifetime, ISOs and, except as the Administrator otherwise expressly provides in accordance with the third sentence of this Section 6(a)(3), SARs and NSOs may be exercised only by the Participant.  The Administrator may permit the gratuitous transfer (i.e., transfer not for value) of Awards other than ISOs, subject to applicable securities and other laws and such limitations as the Administrator may impose.

(4)                                 Vesting.  The Administrator shall determine the time or times at which an Award vests or becomes exercisable and the terms on which a Stock Option or SAR remains exercisable.  Without limiting the foregoing, the Administrator may at any time accelerate the vesting or exercisability of an Award, regardless of any adverse or potentially adverse tax or other consequences resulting from such acceleration.  Unless the Administrator expressly provides otherwise, however, the following rules will apply if a Participant’s Employment ceases:

(A)                               Except as provided in (B) and (C) below, immediately upon the cessation of the Participant’s Employment each Stock Option and SAR that is then held by the Participant or by the Participant’s permitted transferees, if any, will cease to be exercisable and will terminate and all other Awards that are then held by the Participant or by the Participant’s permitted transferees, if any, to the extent not already vested will be forfeited.

(B)                               Subject to (C) and (D) below, all Stock Options and SARs held by the Participant or the Participant’s permitted transferees, if any, immediately prior to the

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cessation of the Participant’s Employment, to the extent then exercisable, will remain exercisable for the lesser of (i) a period of three months or (ii) the period ending on the latest date on which such Stock Option or SAR could have been exercised without regard to this Section 6(a)(4), and will thereupon immediately terminate.

(C)                               Subject to (D) below, all Stock Options and SARs held by a Participant or the Participant’s permitted transferees, if any, immediately prior to the cessation of the Participant’s Employment due to death or Disability, to the extent then exercisable, will remain exercisable for the lesser of (i) the one year period ending with the first anniversary of the Participant’s cessation of Employment or (ii) the period ending on the latest date on which such Stock Option or SAR could have been exercised without regard to this Section 6(a)(4), and will thereupon immediately terminate.  In addition, if the Participant’s Employment ceases for any reason other than pursuant to (D) below and in the three months following such cessation of Employment the Participant dies or experiences a Disability, the exercisability of all Stock Options and SARs held by the Participant or the Participant’s permitted transferees, if any, will automatically be extended upon such event and will remain exercisable for the lesser of (i) the one year period ending with the first anniversary of the Participant’s cessation of Employment or (ii) the period ending on the latest date on which such Stock Option or SAR could have been exercised without regard to this Section 6(a)(4), and will thereupon immediately terminate.

(D)                               All Stock Options and SARs (whether or not exercisable) held by a Participant or the Participant’s permitted transferees, if any, immediately prior to the cessation of the Participant’s Employment will immediately terminate upon such cessation of Employment if the termination is for Cause or occurs in circumstances that in the determination of the Administrator would have constituted grounds for the Participant’s Employment to be terminated for Cause.

(5)                                 Recovery of Compensation.  The Administrator may provide in any case that outstanding Awards (whether or not vested or exercisable) and the proceeds from the exercise or disposition of Awards or Stock acquired under Awards will be subject to forfeiture and disgorgement to the Company, with interest and other related earnings, if the Participant to whom the Award was granted violates (i) a non-competition, non-solicitation, no-hire, non-disparagement, confidentiality, invention assignment or other restrictive covenant by which he or she is bound, or (ii) any Company policy applicable to the Participant that provides for forfeiture or disgorgement with respect to incentive compensation that includes Awards under the Plan.  In addition, the Administrator may require forfeiture and disgorgement to the Company of outstanding Awards and the proceeds from the exercise or disposition of Awards or Stock acquired under Awards, with interest and other related earnings, to the extent required by law or applicable stock exchange listing standards, including, without limitation, Section 10D of the Securities Exchange Act of 1934, as amended, and any related Company policy.  Each Participant, by accepting or being deemed to have accepted an Award under the Plan, agrees to cooperate fully with the Administrator, and to cause any and all permitted transferees of the Participant to cooperate fully with the Administrator, to effectuate any forfeiture or disgorgement required hereunder.  Neither the Administrator nor the Company nor any other person, other than the Participant and his or her permitted transferees, if any, will be responsible for any adverse tax or other consequences to a Participant or his or her permitted transferees, if any, that may arise in connection with this Section 6(a)(5).

(6)                                 Taxes.  The delivery, vesting and retention of Stock, cash or other property under an Award are conditioned upon full satisfaction by the Participant of all tax withholding requirements with respect to the Award.  The Administrator shall prescribe such rules for the withholding of taxes with respect to any Award as it deems necessary.  The Administrator may hold back shares of Stock from an Award or permit a Participant to tender previously owned shares of Stock in satisfaction of tax withholding requirements (but not in

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excess of the maximum withholding amount consistent with the award being subject to equity accounting treatment under the Accounting Rules).

(7)                                 Dividends and Dividend Equivalents.  The Administrator may provide for the payment of amounts (on terms and subject to conditions established by the Administrator) in lieu of cash dividends or other cash distributions with respect to Stock subject to an Award whether or not the holder of such Award is otherwise entitled to share in the actual dividend or distribution in respect of such Award; provided, however, that (a) dividends or dividend equivalents relating to an Award that, at the dividend payment date, remains subject to a risk of forfeiture (whether service-based or performance-based) shall be subject to the same risk of forfeiture as applies to the underlying Award and (b) no dividends or dividend equivalents shall be payable with respect to Options or SARs.  Any entitlement to dividend equivalents or similar entitlements will be established and administered either consistent with an exemption from, or in compliance with, the requirements of Section 409A.  Dividends or dividend equivalent amounts payable in respect of Awards that are subject to restrictions may be subject to such limits or restrictions as the Administrator may impose.

(8)                                 Rights Limited.  Nothing in the Plan may be construed as giving any person the right to be granted an Award or to continued employment or service with the Company or any of its subsidiaries, or any rights as a stockholder except as to shares of Stock actually issued under the Plan.  The loss of existing or potential profit in Awards will not constitute an element of damages in the event of termination of Employment for any reason, even if the termination is in violation of an obligation of the Company or any of its subsidiaries to the Participant.

(9)                                 Section 162(m).  To the extent applicable, Awards granted under this Plan are intended to be eligible for exemption from the limitations of Section 162(m) by reason of the post-initial public offering transition relief set forth in Section 1.162-27(f) of the Treasury Regulations.

(10)                          Coordination with Other Plans.  Awards under the Plan may be granted in tandem with, or in satisfaction of or substitution for, other Awards under the Plan or awards made under other compensatory plans or programs of the Company or any of its subsidiaries.  For example, but without limiting the generality of the foregoing, awards under other compensatory plans or programs of the Company or any of its subsidiaries may be settled in Stock (including, without limitation, Unrestricted Stock) under the Plan if the Administrator so determines, in which case the shares delivered will be treated as awarded under the Plan (and will reduce the number of shares thereafter available under the Plan in accordance with the rules set forth in Section 4).

(11)                          Section 409A.

(A)                               Without limiting the generality of Section 11(b) hereof, each Award will contain such terms as the Administrator determines and will be construed and administered, such that the Award either qualifies for an exemption from the requirements of Section 409A or satisfies such requirements.

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(B)                               Notwithstanding Section 9 of this Plan or any other provision of this Plan or any Award agreement to the contrary, the Administrator may unilaterally amend, modify or terminate the Plan or any outstanding Award, including but not limited to changing the form of the Award, if the Administrator determines that such amendment, modification or termination is necessary or advisable to avoid the imposition of an additional tax, interest or penalty under Section 409A.

(C)                               If a Participant is deemed on the date of the Participant’s termination of Employment to be a “specified employee” within the meaning of that term under Section 409A(a)(2)(B), then, with regard to any payment that is considered nonqualified deferred compensation under Section 409A, to the extent applicable, payable on account of a “separation from service”, such payment will be made or provided on the date that is the earlier of (i) the expiration of the six-month period measured from the date of such “separation from service” and (ii) the date of the Participant’s death (the “Delay Period”).  Upon the expiration of the Delay Period, all payments delayed pursuant to this Section 6(a)(11)(C) (whether they would have otherwise been payable in a single lump sum or in installments in the absence of such delay) will be paid on the first business day following the expiration of the Delay Period in a lump sum and any remaining payments due under the Award will be paid in accordance with the normal payment dates specified for them in the applicable Award agreement.

(D)                               For purposes of Section 409A, each payment made under this Plan will be treated as a separate payment.

(E)                               With regard to any payment considered to be nonqualified deferred compensation under Section 409A, to the extent applicable, that is payable upon a change in control of the Company or other similar event, to avoid the imposition of an additional tax, interest or penalty under Section 409A, no amount will be payable unless such change in control constitutes a “change in control event” within the meaning of Section 1.409A-3(i)(5) of the Treasury Regulations.

(b)                                 Stock Options and SARs.

(1)                                 Time and Manner of Exercise.  Unless the Administrator expressly provides otherwise, no Stock Option or SAR will be deemed to have been exercised until the Administrator receives notice of exercise in a form acceptable to the Administrator that is signed by the appropriate person and accompanied by any payment required under the Award.  Any attempt to exercise a Stock Option or SAR by any person other than the Participant will not be given effect unless the Administrator has received such evidence as it may require that the person exercising the Award has the right to do so.

(2)                                 Exercise Price.  The exercise price (or the base value from which appreciation is to be measured) of each Award requiring exercise must be no less than 100% (in the case of an ISO granted to a 10-percent stockholder within the meaning of subsection (b)(6) of Section 422, 110%) of the Fair Market Value of the Stock subject to the Award, determined as of

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the date of grant, or such higher amount as the Administrator may determine in connection with the grant.

(3)                                 Payment of Exercise Price.  Where the exercise of an Award is to be accompanied by payment, payment of the exercise price must be by cash or check acceptable to the Administrator or, if so permitted by the Administrator and if legally permissible, (i) through the delivery of previously acquired unrestricted shares of Stock, or the withholding of unrestricted shares of Stock otherwise deliverable upon exercise, in either case that have a Fair Market Value equal to the exercise price, (ii) through a broker-assisted exercise program acceptable to the Administrator, (iii) by other means acceptable to the Administrator, or (iv) by any combination of the foregoing permissible forms of payment.  The delivery of previously acquired shares in payment of the exercise price under clause (i) above may be accomplished either by actual delivery or by constructive delivery through attestation of ownership, subject to such rules as the Administrator may prescribe.

(4)                                 Maximum Term.  The maximum term of Stock Options and SARs must not exceed 10 years from the date of grant (or five years from the date of grant in the case of an ISO granted to a 10-percent stockholder described in Section 6(b)(2) above).

(5)                                 No Repricing.  Except in connection with a corporate transaction involving the Company (which term includes, without limitation, any stock dividend, stock split, extraordinary cash dividend, recapitalization, reorganization, merger, consolidation, split-up, spin-off, combination or exchange of shares) or as otherwise contemplated by Section 7 below, the Company may not, without obtaining stockholder approval, (A) amend the terms of outstanding Stock Options or SARs to reduce the exercise price or base value of such Stock Options or SARs, (B) cancel outstanding Stock Options or SARs in exchange for Stock Options or SARs with an exercise price or base value that is less than the exercise price or base value of the original Stock Options or SARs, or (C) cancel outstanding Stock Options or SARs that have an exercise price or base value greater than the Fair Market Value of a share of Stock on the date of such cancellation in exchange for cash or other consideration.

7.                                      EFFECT OF CERTAIN TRANSACTIONS

(a)                                 Covered Transactions.  Except as otherwise expressly provided in an Award agreement or by the Administrator, the following provisions will apply in the event of a Covered Transaction:

(1)                                 Assumption or Substitution.  If the Covered Transaction is one in which there is an acquiring or surviving entity, the Administrator may provide for (A) the assumption or continuation of some or all outstanding Awards or any portion thereof or (B) the grant of new awards in substitution therefor by the acquiror or survivor or an affiliate of the acquiror or survivor.

(2)                                 Cash-Out of Awards.  Subject to Section 7(a)(5) below, the Administrator may provide for payment (a “cash-out”), with respect to some or all Awards or any portion thereof, equal in the case of each affected Award or portion thereof to the excess, if any, of (A) the Fair Market Value of one share of Stock times the number of shares of Stock

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subject to the Award or such portion, over (B) the aggregate exercise or purchase price, if any, under the Award or such portion (in the case of a SAR, the aggregate base value above which appreciation is measured), in each case on such payment terms (which need not be the same as the terms of payment to holders of Stock) and other terms, and subject to such conditions, as the Administrator determines; provided, however, for the avoidance of doubt, that if the exercise or purchase price (or base value) of an Award is equal to or greater than the Fair Market Value of one share of Stock, the Award may be cancelled with no payment due hereunder or otherwise in respect of such Award.

(3)                                 Acceleration of Certain Awards.  Subject to Section 7(a)(5) below, the Administrator may provide that any Award requiring exercise will become exercisable, in full or in part, and/or that the delivery of any shares of Stock remaining deliverable under any outstanding Award of Stock Units (including Restricted Stock Units and Performance Awards to the extent consisting of Stock Units) will be accelerated, in full or in part, in each case on a basis that gives the holder of the Award a reasonable opportunity, as determined by the Administrator, following exercise of the Award or the delivery of the shares, as the case may be, to participate as a stockholder in the Covered Transaction.

(4)                                 Termination of Awards upon Consummation of a Covered Transaction.  Except as the Administrator may otherwise determine in any case, each Award will automatically terminate (and in the case of outstanding shares of Restricted Stock, will automatically be forfeited) immediately upon consummation of the Covered Transaction, other than any Award that is assumed or substituted pursuant to Section 7(a)(1) above.

(5)                                 Additional Limitations.  Any share of Stock and any cash or other property or other award delivered pursuant to Section 7(a)(1), Section 7(a)(2) or Section 7(a)(3) above with respect to an Award may, in the discretion of the Administrator, contain such restrictions, if any, as the Administrator deems appropriate to reflect any performance or other vesting conditions to which the Award was subject and that did not lapse (and were not satisfied) in connection with the Covered Transaction.  For purposes of the immediately preceding sentence, a cash-out under Section 7(a)(2) above or an acceleration under Section 7(a)(3) above will not, in and of itself, be treated as the lapsing (or satisfaction) of a performance or other vesting condition.  In the case of Restricted Stock that does not vest and is not forfeited in connection with the Covered Transaction, the Administrator may require that any amounts delivered, exchanged or otherwise paid in respect of such Stock in connection with the Covered Transaction be placed in escrow or otherwise made subject to such restrictions as the Administrator deems appropriate to carry out the intent of the Plan.

(b)                                 Changes in and Distributions with Respect to Stock.

(1)                                 Basic Adjustment Provisions.  In the event of a stock dividend, stock split or combination of shares (including a reverse stock split), recapitalization or other change in the Company’s capital structure that constitutes an equity restructuring within the meaning of the Accounting Rules, the Administrator shall make appropriate adjustments to the maximum number of shares of Stock specified in Section 4(a) that may be issued under the Plan and to the maximum share limits described in Section 4(d), and shall make appropriate adjustments to the number and kind of shares of stock or securities underlying Awards then outstanding or

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subsequently granted, any exercise or purchase prices (or base values) relating to Awards and any other provision of Awards affected by such change.

(2)                                 Certain Other Adjustments.  The Administrator may also make adjustments of the type described in Section 7(b)(1) above to take into account distributions to stockholders other than those provided for in Section 7(a) and 7(b)(1), or any other event, if the Administrator determines that adjustments are appropriate to avoid distortion in the operation of the Plan, having due regard for the qualification of ISOs under Section 422 and the requirements of Section 409A, to the extent applicable.

(3)                                 Continuing Application of Plan Terms.  References in the Plan to shares of Stock will be construed to include any stock or securities resulting from an adjustment pursuant to this Section 7.

8.                                      LEGAL CONDITIONS ON DELIVERY OF STOCK

The Company will not be obligated to deliver any shares of Stock pursuant to the Plan or to remove any restriction from shares of Stock previously delivered under the Plan until: (i) the Company is satisfied that all legal matters in connection with the issuance and delivery of such shares have been addressed and resolved; (ii) if the outstanding Stock is at the time of delivery listed on any stock exchange or national market system, the shares to be delivered have been listed or authorized to be listed on such exchange or system upon official notice of issuance; and (iii) all conditions of the Award have been satisfied or waived.  The Company may require, as a condition to the exercise of an Award or the delivery of shares of Stock under an Award, such representations or agreements as counsel for the Company may consider appropriate to avoid violation of the Securities Act of 1933, as amended, or any applicable state or non-U.S. securities law.  Any Stock required to be issued to Participants under the Plan will be evidenced in such manner as the Administrator may deem appropriate, including book-entry registration or delivery of stock certificates.  In the event that the Administrator determines that stock certificates will be issued to Participants under the Plan, the Administrator may require that certificates evidencing Stock issued under the Plan bear an appropriate legend reflecting any restriction on transfer applicable to such Stock, and the Company may hold the certificates pending lapse of the applicable restrictions.

9.                                      AMENDMENT AND TERMINATION

The Administrator may at any time or times amend the Plan or any outstanding Award for any purpose which may at the time be permitted by law, and may at any time terminate the Plan as to any future grants of Awards; provided, however, that except as otherwise expressly provided in the Plan the Administrator may not, without the Participant’s consent, alter the terms of an Award so as to affect materially and adversely the Participant’s rights under the Award, unless the Administrator expressly reserved the right to do so at the time the Award was granted.  Any amendments to the Plan will be conditioned upon stockholder approval only to the extent, if any, such approval is required by law (including the Code) or applicable stock exchange requirements, as determined by the Administrator.

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10.                               OTHER COMPENSATION ARRANGEMENTS

The existence of the Plan or the grant of any Award will not affect the Company’s right to award a person bonuses or other compensation in addition to Awards under the Plan.

11.                               MISCELLANEOUS

(a)                                 Waiver of Jury Trial.  By accepting or being deemed to have accepted an Award under the Plan, each Participant waives any right to a trial by jury in any action, proceeding or counterclaim concerning any rights under the Plan and any Award, or under any amendment, waiver, consent, instrument, document or other agreement delivered or which in the future may be delivered in connection therewith, and agrees that any such action, proceedings or counterclaim will be tried before a court and not before a jury.  By accepting or being deemed to have accepted an Award under the Plan, each Participant certifies that no officer, representative, or attorney of the Company has represented, expressly or otherwise, that the Company would not, in the event of any action, proceeding or counterclaim, seek to enforce the foregoing waivers.  Notwithstanding anything to the contrary in the Plan, nothing herein is to be construed as limiting the ability of the Company and a Participant to agree to submit disputes arising under the terms of the Plan or any Award made hereunder to binding arbitration or as limiting the ability of the Company to require any eligible individual to agree to submit such disputes to binding arbitration as a condition of receiving an Award hereunder.

(b)                                 Limitation of Liability.  Notwithstanding anything to the contrary in the Plan, neither the Company, nor any of its subsidiaries, nor the Administrator, nor any person acting on behalf of the Company, any of its subsidiaries, or the Administrator, will be liable to any Participant, to any permitted transferee, to the estate or beneficiary of any Participant or any permitted transferee, or to any other holder of an Award by reason of any acceleration of income, or any additional tax (including any interest and penalties), asserted by reason of the failure of an Award to satisfy the requirements of Section 422 or Section 409A or by reason of Section 4999 of the Code, or otherwise asserted with respect to the Award.

12.                               ESTABLISHMENT OF SUB-PLANS

The Administrator may at any time and from time to time establish one or more sub-plans under the Plan (for local-law compliance purposes or other administrative reasons determined by the Administrator) by adopting supplements to the Plan containing, in each case, such limitations on the Administrator’s discretion under the Plan, and such additional terms and conditions, as the Administrator deems necessary or desirable.  Each supplement so established will be deemed to be part of the Plan but will apply only to Participants within the group to which the supplement applies (as determined by the Administrator).

13.                               GOVERNING LAW

(a)                                 Certain Requirements of Corporate Law.  Awards will be granted and administered consistent with the requirements of applicable Massachusetts law relating to the issuance of stock and the consideration to be received therefor, and with the applicable requirements of the stock exchanges or other trading systems on which the Stock is listed or entered for trading, in each case as determined by the Administrator.

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(b)           Other Matters.  Except as otherwise provided by the express terms of an Award agreement, under a sub-plan described in Section 12 or as provided in Section 13(a) above, the domestic substantive laws of the Commonwealth of Massachusetts govern the provisions of the Plan and of Awards under the Plan and all claims or disputes arising out of or based upon the Plan or any Award under the Plan or relating to the subject matter hereof or thereof without giving effect to any choice or conflict of laws provision or rule that would cause the application of the domestic substantive laws of any other jurisdiction.

(c)           Jurisdiction.  By accepting an Award, each Participant will be deemed to (a) have submitted irrevocably and unconditionally to the jurisdiction of the federal and state courts located within the geographic boundaries of the United States District Court for the District of Massachusetts for the purpose of any suit, action or other proceeding arising out of or based upon the Plan or any Award; (b) agree not to commence any suit, action or other proceeding arising out of or based upon the Plan or an Award, except in the federal and state courts located within the geographic boundaries of the United States District Court for the District of Massachusetts; and (c) waive, and agree not to assert, by way of motion as a defense or otherwise, in any such suit, action or proceeding, any claim that he or she is not subject personally to the jurisdiction of the above-named courts that his or her property is exempt or immune from attachment or execution, that the suit, action or proceeding is brought in an inconvenient forum, that the venue of the suit, action or proceeding is improper or that the Plan or an Award or the subject matter thereof may not be enforced in or by such court.

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EXHIBIT A

Definition of Terms

The following terms, when used in the Plan, have the meanings and are subject to the provisions set forth below:

“Accounting Rules”:  Financial Accounting Standards Board Accounting Standards Codification Topics 505 and 718, as applicable, or any successor provision.

“Administrator”:  The Compensation Committee, except that the Compensation Committee may delegate (i) to one or more of its members (or one or more other members of the Board, including the full Board) such of its duties, powers and responsibilities as it may determine; and (ii) to such Employees or other persons as it determines such ministerial tasks as it deems appropriate.  In the event of any delegation described in the preceding sentence, the term “Administrator” will include the person or persons so delegated to the extent of such delegation.

“Award”:  Any or a combination of the following:

(i) Stock Options.

(ii) SARs.

(iii) Restricted Stock.

(iv) Unrestricted Stock.

(v) Stock Units, including Restricted Stock Units.

(vi) Performance Awards.

(vii) Awards (other than Awards described in (i) through (vi) above) that are convertible into or otherwise based on Stock.

“Board”:  The Board of Directors of the Company.

“Cause”:  In the case of any Participant who is party to an employment or severance-benefit agreement that contains a definition of “Cause,” the definition set forth in such agreement applies with respect to such Participant for purposes of the Plan for so long as such agreement is in effect.  In every other case, “Cause” means, as determined by the Administrator, (i) a substantial failure of the Participant to perform the Participant’s duties and responsibilities to the Company or any of its subsidiaries or substantial negligence in the performance of such duties and responsibilities; (ii) the commission by the Participant of a felony or a crime involving moral turpitude; (iii) the commission by the Participant of theft, fraud, embezzlement, breach of trust or any act of dishonesty involving the Company or any of its subsidiaries; (iv) a significant violation by the Participant of the code of conduct of the Company or any of its subsidiaries of any material policy of the Company or any of its subsidiaries, or of any statutory or common law

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duty of loyalty to the Company or any of its subsidiaries; (v) breach of any of the terms of the Plan or any Award made under the Plan, or of the terms of any other agreement between the Company or any of its subsidiaries and the Participant; or (vi) other conduct by the Participant that could be expected to be harmful to the business, interests or reputation of the Company.

“Code”:  The U.S. Internal Revenue Code of 1986, as from time to time amended and in effect, or any successor statute as from time to time in effect.

“Compensation Committee”:  The Compensation Committee of the Board.

“Company”:  Cyclerion Therapeutics, Inc., a Massachusetts corporation.

“Covered Transaction”:  Any of (i) a consolidation, merger or similar transaction or series of related transactions, including a sale or other disposition of stock, in which the Company is not the surviving corporation or which results in the acquisition of all or substantially all of the Company’s then outstanding common stock by a single person or entity or by a group of persons and/or entities acting in concert, (ii) a sale or transfer of all or substantially all the Company’s assets, or (iii) a dissolution or liquidation of the Company.  Where a Covered Transaction involves a tender offer that is reasonably expected to be followed by a merger described in clause (i) (as determined by the Administrator), the Covered Transaction will be deemed to have occurred upon consummation of the tender offer.

“Date of Adoption”:  The earlier of the date the Plan was approved by the Company’s stockholders or adopted by the Board, as determined by the Committee.

“Director”:  A member of the Board who is not an Employee.

“Disability”:  A disability that would entitle the Participant to long-term disability benefits under the Company’s long-term disability plan in which the Participant participates.  If a Participant does not participate in a long-term disability plan of the Company, Disability means a permanent and total disability as defined in Section 22(e)(3) of the Code.

“Employee”:  Any person who is employed by the Company or any of its subsidiaries.

“Employment”:  A Participant’s employment or other service relationship with the Company or any of its subsidiaries.  Employment will be deemed to continue, unless the Administrator expressly provides otherwise, so long as the Participant is employed by, or otherwise is providing services in a capacity described in Section 5 to, the Company or any of its subsidiaries.  If a Participant’s employment or other service relationship is with any subsidiary of the Company and that entity ceases to be a subsidiary of the Company, the Participant’s Employment will be deemed to have terminated when the entity ceases to be a subsidiary of the Company unless the Participant transfers Employment to the Company or any of its remaining subsidiaries.  Notwithstanding the foregoing, in construing the provisions of any Award relating to the payment of “nonqualified deferred compensation” (subject to Section 409A) upon a termination or cessation of Employment, references to termination or cessation of employment, separation from service, retirement or similar or correlative terms will be construed to require a “separation from service” (as that term is defined in Section 1.409A-1(h) of the Treasury Regulations) from the Company and from all other corporations and trades or businesses, if any, that would be treated as a single “service recipient” with the Company under Section 1.409A-1(h)(3) of the Treasury Regulations.  The Company may, but need not, elect in writing, subject to the applicable limitations under Section 409A, any of the special elective rules prescribed in Section 1.409A-1(h) of the Treasury Regulations for purposes of determining whether a

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“separation from service” has occurred.  Any such written election will be deemed a part of the Plan.

“Fair Market Value”:  As of a particular date, (i) the closing price for a share of Stock reported on the Nasdaq Stock Market (or any other national securities exchange on which the Stock is then listed) for that date or, if no closing price is reported for that date, the closing price on the immediately preceding date on which a closing price was reported or (ii) in the event that the Stock is not traded on a national securities exchange, the fair market value of a share of Stock determined by the Administrator consistent with the rules of Section 422 and Section 409A to the extent applicable.

“ISO”:  A Stock Option intended to be an “incentive stock option” within the meaning of Section 422.  Each Stock Option granted pursuant to the Plan will be treated as providing by its terms that it is to be an NSO unless, as of the date of grant, it is expressly designated as an ISO.

“NSO”:  A Stock Option that is not intended to be an “incentive stock option” within the meaning of Section 422.

“Participant”:  A person who is granted an Award under the Plan.

“Performance Award”:  An Award subject to Performance Criteria.

“Performance Criteria”:  Specified criteria, other than the mere continuation of Employment or the mere passage of time, the satisfaction of which is a condition for the grant, exercisability, vesting or full enjoyment of an Award.  A Performance Criterion and any targets with respect thereto need not be based upon an increase, a positive or improved result or avoidance of loss and may be applied to the Participant individually, or to a business unit or division or the Company as a whole and may relate to any or any combination of the following (measured either absolutely or by reference to an index or indices or the performance of one or more companies and determined either on a consolidated basis or, as the context permits, on a divisional, subsidiary, line of business, project or geographical basis or in combinations thereof): achievement of research, clinical trial or other drug development objectives; achievement of regulatory objectives; achievement of manufacturing and/or supply chain objectives; sales; revenues; assets; expenses; earnings before or after deduction for all or any portion of interest, taxes, depreciation, or amortization, whether or not on a continuing operations or an aggregate or per share basis; return on equity, investment, capital or assets; one or more operating ratios; borrowing levels, leverage ratios or credit rating; market share; capital expenditures; cash flow; stock price; stockholder return; sales of particular products or services; customer acquisition or retention; acquisitions and divestitures (in whole or in part); joint ventures, licenses and strategic alliances; spin-offs, split-ups and the like; reorganizations; or recapitalizations, restructurings, financings (issuance of debt or equity) or refinancings.  The Administrator may provide that one or more of the Performance Criteria applicable to such Award will be adjusted to reflect events (including, but not limited to, the impact of charges for restructurings, discontinued operations, mergers, acquisitions, extraordinary items, and other unusual or non-recurring items, and the cumulative effects of tax or accounting changes, each as defined by U.S. generally accepted accounting principles) occurring during the applicable performance period that affect the applicable Performance Criterion or Criteria.

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“Plan”:  The Cyclerion Therapeutics, Inc. 2019 Incentive Plan, as from time to time amended and in effect.

“Restricted Stock”:  Stock subject to restrictions requiring that it be forfeited, redelivered or offered for sale to the Company if specified service or performance-based conditions are not satisfied.

“Restricted Stock Unit”:  A Stock Unit that is, or as to which the delivery of Stock or cash in lieu of Stock is, subject to the satisfaction of specified performance or other vesting conditions.

“SAR”:  A right entitling the holder upon exercise to receive an amount (payable in cash or in shares of Stock of equivalent value) equal to the excess of the Fair Market Value of the shares of Stock subject to the right over the base value from which appreciation under the SAR is to be measured.

“Section 409A”:  Section 409A of the Code.

“Section 422”:  Section 422 of the Code.

“Section 162(m)”:  Section 162(m) of the Code.

“Stock”:  Common stock of the Company, par value $0.00 per share.

“Stock Option”:  An option entitling the holder to acquire shares of Stock upon payment of the exercise price.

“Stock Unit”:  An unfunded and unsecured promise, denominated in shares of Stock, to deliver Stock or cash measured by the value of Stock in the future.

“Substitute Awards”:  Awards issued under the Plan in substitution for equity awards of an acquired company that are converted, replaced or adjusted in connection with the acquisition.

“Unrestricted Stock”:  Stock not subject to any restrictions under the terms of the Award.

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Exhibit 4.5

CYCLERION THERAPEUTICS, INC.

AMENDED AND RESTATED 2010 EMPLOYEE, DIRECTOR AND CONSULTANT EQUITY INCENTIVE PLAN

1.                                      DEFINITIONS.

Unless otherwise specified or unless the context otherwise requires, the following terms, as used in this Cyclerion Therapeutics, Inc.  Amended and Restated 2010 Employee, Director and Consultant Equity Incentive Plan, have the following meanings:

Administrator means the Board of Directors, unless it has delegated power to act on its behalf to the Committee, in which case the Administrator means the Committee.

Affiliate means a corporation which, for purposes of Section 424 of the Code, is a parent or subsidiary of the Company, direct or indirect.

Agreement means an agreement between the Company and a Participant delivered pursuant to the Plan and pertaining to a Stock Right, in such form as the Administrator shall approve.

Board of Directors means the Board of Directors of the Company.

Cause means, with respect to a Participant (a) dishonesty with respect to the Company or any Affiliate, (b) insubordination, substantial malfeasance or non-feasance of duty, (c) unauthorized disclosure of confidential information, (d) breach by a Participant of any provision of any employment, consulting, advisory, nondisclosure, non-competition or similar agreement between the Participant and the Company or any Affiliate, and (e) conduct substantially prejudicial to the business of the Company or any Affiliate; provided, however, that this definition of “Cause” shall be superseded by (i) the definition of “Cause” contained in an agreement between a Participant and the Company or any Affiliate which is in effect at the time of such termination, with respect to that Participant and (ii) the definition of “Cause” contained in the Company’s Change of Control Severance Benefit Plan to the extent such plan is in effect at the time of such termination, the Participant is a participant in such plan and such termination occurs within the period during which the Participant is eligible for enhanced severance benefits under the Company’s Change of Control Severance Benefit Plan.  The determination of the Administrator as to the existence of Cause will be conclusive on the Participant and the Company; provided, however, that if the determination is made within the period during which the Participant is eligible for enhanced severance benefits under the Company’s Change of Control Severance Benefit Plan, then the determination will be subject to de novo review.

Code means the United States Internal Revenue Code of 1986, as amended including any successor statute, regulation and guidance thereto.

Committee means the committee of the Board of Directors to which the Board of Directors has delegated power to act under or pursuant to the provisions of the Plan, or a subcommittee thereof that consists solely of two or more “outside” directors, as required under Section 162(m) of the Code.

Common Stock means common stock of the Company.

Company means Cyclerion Therapeutics, Inc., a Massachusetts corporation.

Consultant means any natural person who (i) is an advisor or consultant that provides bona fide services to the Company or its Affiliates or to Ironwood, provided that such services are not in connection with the offer or sale of securities in a capital raising transaction, and do not directly or indirectly promote or maintain a market for the Company’s or its Affiliates’ securities and (ii) was granted one or more Stock Rights under the Plan prior to the separation of the Company from Ironwood.

Disability or Disabled means permanent and total disability as defined in Section 22(e)(3) of the Code.

Employee means any employee of the Company or an Affiliate or of Ironwood (including, without limitation, an employee who is also serving as an officer or director of the Company or an Affiliate or of Ironwood), to whom one or more Stock Rights were granted under the Plan prior to the separation of the Company from Ironwood.

Exchange Act means the Securities Exchange Act of 1934, as amended.

Fair Market Value of a Share of Common Stock means:

(1)                                 If the Common Stock is listed on a national securities exchange or traded in the over-the-counter market and sales prices are regularly reported for the Common Stock, the closing or, if not applicable, the last price of the Common Stock on the composite tape or other comparable reporting system for the trading day on the applicable date and if such applicable date is not a trading day, the last market trading day prior to such date;

(2)                                 If the Common Stock is not traded on a national securities exchange but is traded on the over-the-counter market, if sales prices are not regularly reported for the Common Stock for the trading day referred to in clause (1), and if bid and asked prices for the Common Stock are regularly reported, the mean between the bid and the asked price for the Common Stock at the close of trading in the over-the-counter market for the trading day on which Common Stock was traded on the applicable date and if such applicable date is not a trading day, the last market trading day prior to such date; and

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(3)                                 If the Common Stock is neither listed on a national securities exchange nor traded in the over-the-counter market, such value as the Administrator, in good faith, shall determine.

Ironwood means Ironwood Pharmaceuticals, Inc.

ISO means an option meant to qualify as an incentive stock option under Section 422 of the Code.

Non-Qualified Option means an option which is not intended to qualify as an ISO.

Option means an ISO or Non-Qualified Option granted under the Plan.

Participant means an Employee, Consultant or director of the Company or an Affiliate or of Ironwood to whom one or more Stock Rights were granted under the Plan prior to the separation of the Company from Ironwood.  As used herein, “Participant” shall include “Participant’s Survivors” where the context requires.

Performance-Based Award means a Stock Right as set forth in Paragraph 9 hereof.

Performance Goals means performance goals based on one or more of the following criteria: achievement of research, clinical trial or other drug development objectives; achievement of regulatory objectives; achievement of manufacturing and/or supply chain objectives; sales; revenues; assets; expenses; earnings or earnings per share; earnings before interest and taxes (EBIT) or EBIT per share; earnings before interest, taxes, depreciation and amortization (EBITDA) or EBITDA per share; return on equity, investment, capital or assets; one or more operating ratios; borrowing levels, leverage ratios or credit rating; market share; capital expenditures; cash flow or cash flow per share; stock price; stockholder return; income, pre-tax income, net income, operating income, pre-tax profit, operating profit, net operating profit or economic profit; gross margin, operating margin, profit margin, return on operating revenue, return on operating assets, cash from operations, operating ratio or operating revenue; market capitalization; customer expansion or retention; acquisitions or divestitures (in whole or in part) and/or integration activities related thereto; joint ventures, collaborations, licenses and strategic alliances, and/or the management and performance of such relationships; spin-offs, split-ups or similar transactions; reorganizations; recapitalizations, restructurings, financings (issuance of debt or equity) or refinancings; achievement of litigation-related objectives and/or objectives related to litigation expenses; achievement of human resource, organizational and/or personnel objectives; achievement of information technology or information services objectives; or achievement of real estate, facilities or space-planning objectives.

The foregoing performance goals may be determined: (a) on an absolute basis, (b) relative to internal goals or levels attained in prior years, (c) related to other companies or indices, or (d) as ratios expressing relationships between two or

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more Performance Goals.  Where applicable, the Performance Goals may be expressed in terms of attaining a specified level of the particular criterion or the attainment of a percentage increase or decrease in the particular criterion, and may be applied to the Company and/or an Affiliate, or a division or strategic business unit of the Company and/or an Affiliate, all as determined by the Committee.  The Performance Goals may include a threshold level of performance below which no Performance-Based Award will be issued or no vesting will occur, levels of performance at which Performance-Based Awards will be issued or specified vesting will occur, and a maximum level of performance above which no additional issuances will be made or at which full vesting will occur.  In the areas of drug research, development, regulatory affairs and commercialization, if a third party partner that is party to a licensing or collaboration agreement with the Company accomplishes a development milestone, regulatory achievement, or commercialization or sales target with the partnered asset, then such third party partner’s accomplishment shall constitute an achievement of the Company.

The satisfaction of each of the foregoing Performance Goals shall be subject to certification by the Committee.  The Committee has the authority to take appropriate action with respect to the Performance Goals (including, without limitation, to make adjustments to the Performance Goals or determine the satisfaction of the Performance Goals, in each case, in connection with a Corporate Transaction) provided that any such actions do not otherwise violate Section 162(m) of the Code or the terms of the Plan.  In the case of Performance-Based Awards that are not intended to comply with Section 162(m) of the Code, the Committee may designate performance criteria from among the foregoing or such other performance criteria as it shall determine in its sole discretion.

Plan means this Cyclerion Therapeutics, Inc.  Amended and Restated 2010 Employee, Director and Consultant Equity Incentive Plan.

Securities Act means the Securities Act of 1933, as amended.

Shares means shares of the Common Stock as to which Stock Rights have been or may be granted under the Plan or any shares of capital stock into which the Shares are changed or for which they are exchanged within the provisions of Paragraph 3 of the Plan.  The Shares issued under the Plan may be authorized and unissued shares or shares held by the Company in its treasury, or both.

Stock-Based Award means a grant by the Company under the Plan of an equity award or an equity-based award which is not an Option or a Stock Grant.

Stock Grant means a grant by the Company of Shares under the Plan.

Stock Right means a right to Shares or the value of Shares of the Company granted pursuant to the Plan — an ISO, a Non-Qualified Option, a Stock Grant or a Stock-Based Award.

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Survivor means a deceased Participant’s legal representatives and/or any person or persons who acquired the Participant’s rights to a Stock Right by will or by the laws of descent and distribution.

2.                                      PURPOSES OF THE PLAN.

The Plan is intended to encourage ownership of Shares by Employees, Consultants and directors of the Company, its Affiliates or Ironwood to whom one or more Stock Rights were granted under the Plan prior to the separation of the Company from Ironwood, in order to attract and retain such people, to induce them to work for the benefit of the Company or of an Affiliate and to provide additional incentive for them to promote the success of the Company or of an Affiliate.  The Plan provides for the granting of ISOs, Non-Qualified Options, Stock Grants and Stock-Based Awards.  The Plan has been adopted by the Board of Directors solely for the purpose of granting Stock Rights in respect of equity-based awards previously granted under the Ironwood Pharmaceuticals, Inc. Amended and Restated 2010 Employee, Director and Consultant Equity Incentive Plan (the “Ironwood 2010 Plan”) and converted into equity-based awards of the Company pursuant to Article 5 of the Employee Matters Agreement by and between Ironwood Pharmaceuticals, Inc. and the Company dated as of            2019 (the “Employee Matters Agreement”).  The Plan is intended to mirror in all material respects the terms and conditions of the Ironwood 2010 Plan (other than those terms that are made inoperative by the separation of the Company’s soluble guanylate cyclase business from Ironwood Pharmaceuticals, Inc.)

3.                                      SHARES SUBJECT TO THE PLAN.

(a)                                 The number of Shares which may be issued from time to time pursuant to this Plan shall be the lesser of (i) 13,800,000 Shares and (ii) that number of Shares necessary to give effect to the grant of equity-based awards contemplated by Article 5 of the Employee Matters Agreement. Any Shares underlying Stock Rights that are forfeited, expired or are cancelled without the delivery of Shares thereunder, shall be added to the number of Shares that may be issued in satisfaction of awards under the Company’s 2019 Equity Incentive Plan.

4.                                      ADMINISTRATION OF THE PLAN.

The Administrator of the Plan will be the Board of Directors, except to the extent the Board of Directors delegates its authority to the Committee, in which case the Committee shall be the Administrator.

Subject to the provisions of the Plan, the Administrator is authorized to:

(a)                                 Interpret the provisions of the Plan and all Stock Rights and to make all rules and determinations which it deems necessary or advisable for the administration of the Plan;

(b)                                 Determine which Employees, directors and Consultants shall be granted Stock Rights;

(c)                                  Determine the number of Shares for which a Stock Right or Stock Rights shall be granted; provided, however, that in no event shall Stock Rights with respect to more than 1,000,000 Shares be granted to any Participant in any fiscal year (it being understood, however, that all equity-based awards previously granted under the Ironwood 2010 Plan are Stock Rights assumed under the Plan, and are, therefore, not subject to this limitation);

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(d)                                 Specify the terms and conditions upon which a Stock Right or Stock Rights may be granted;

(e)                                  Determine Performance Goals; and

(f)                                   Adopt any sub-plans applicable to residents of any specified jurisdiction as it deems necessary or appropriate in order to comply with or take advantage of any tax or other laws applicable to the Company, any Affiliate or to Participants or to otherwise facilitate the administration of the Plan, which sub-plans may include additional restrictions or conditions applicable to Stock Rights or Shares issuable pursuant to a Stock Right; provided, however, that all such interpretations, rules, determinations, terms and conditions shall be made and prescribed in the context of: (i) not causing any adverse tax consequences under Section 409A of the Code and (ii) preserving the tax status under Section 422 of the Code of those Options which are designated as ISOs.  Subject to the foregoing and except as otherwise provided in the definition of Cause provided in Paragraph 1 above, the interpretation and construction by the Administrator of any provisions of the Plan or of any Stock Right granted under it shall be final, unless otherwise determined by the Board of Directors, if the Administrator is the Committee.  In addition, if the Administrator is the Committee, the Board of Directors may take any action under the Plan that would otherwise be the responsibility of the Committee.

To the extent permitted under applicable law, the Board of Directors or the Committee may allocate all or any portion of its responsibilities and powers to any one or more of its members and may delegate all or any portion of its responsibilities and powers to any other person selected by it.  The Board of Directors or the Committee may revoke any such allocation or delegation at any time.  Notwithstanding the foregoing, only the Board of Directors or the Committee shall be authorized to grant a Stock Right to any director of the Company or to any “officer” of the Company (as defined by Rule 16a-1 under the Exchange Act).

5.                                      ELIGIBILITY FOR PARTICIPATION.

All Employees, Consultants and directors of the Company, its Affiliates or Ironwood to whom one or more Stock Rights were granted under the Plan prior to the separation of the Company from Ironwood are eligible to participate in the Plan.

6.                                      TERMS AND CONDITIONS OF OPTIONS.

Each Option shall be set forth in writing in an Option Agreement, duly executed by the Company and, to the extent required by law or requested by the Company, by the Participant.  The Administrator may provide that Options be granted subject to such terms and conditions, consistent with the terms and conditions specifically required under this Plan, as the Administrator may deem appropriate including, without limitation, subsequent approval by the shareholders of the Company of this Plan or any amendments thereto.  The Option Agreements shall be subject to at least the following terms and conditions:

(a)                                 Non-Qualified Options: Each Option intended to be a Non-Qualified Option shall be subject to the terms and conditions which the Administrator determines to be appropriate and in the best interest of the Company, subject to the following minimum standards for any such Non-Qualified Option:

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(i)                                     Exercise Price: Each Option Agreement shall state the exercise price (per share) of the Shares covered by each Option, which exercise price shall be determined by the Administrator and shall be at least equal to the Fair Market Value per share of Common Stock on the date of grant of the Option.

(ii)                                  Number of Shares: Each Option Agreement shall state the number of Shares to which it pertains.

(iii)                               Option Periods: Each Option Agreement shall state the date or dates on which it first is exercisable and the date after which it may no longer be exercised, and may provide that the Option rights accrue or become exercisable in installments over a period of months or years, or upon the occurrence of certain conditions or the attainment of stated goals or events.

(iv)                              Option Conditions: Exercise of any Option may be conditioned upon the Participant’s execution of a Share purchase agreement in form satisfactory to the Administrator providing for certain protections for the Company and its other shareholders, including requirements that:

(A)                               The Participant’s or the Participant’s Survivors’ right to sell or transfer the Shares may be restricted; and

(B)                               The Participant or the Participant’s Survivors may be required to execute letters of investment intent and must also acknowledge that the Shares will bear legends noting any applicable restrictions.

(b)                                 ISOs: Each Option intended to be an ISO shall be issued only to an Employee who is deemed to be a resident of the United States for tax purposes, and shall be subject to the following terms and conditions, with such additional restrictions or changes as the Administrator determines are appropriate but not in conflict with Section 422 of the Code and relevant regulations and rulings of the Internal Revenue Service:

(i)                                     Minimum Standards: The ISO shall meet the minimum standards required of Non-Qualified Options, as described in Subparagraph 6(a) above, except Subclause (i) thereunder.

(ii)                                  Exercise Price: Immediately before the ISO is granted, if the Participant owns, directly or by reason of the applicable attribution rules in Section 424(d) of the Code:

(A)                               10% or less of the total combined voting power of all classes of stock of the Company or an Affiliate, the exercise price per share of the Shares covered by each ISO shall not be less than 100% of the Fair Market Value per share of the Common Stock on the date of grant of the Option; or

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(B)                               More than 10% of the total combined voting power of all classes of stock of the Company or an Affiliate, the exercise price per share of the Shares covered by each ISO shall not be less than 110% of the Fair Market Value per share of the Common Stock on the date of grant of the Option.

(iii)                               Term of Option: For Participants who own:

(A)                               10%                       or less of the total combined voting power of all classes of stock of the Company or an Affiliate, each ISO shall terminate not more than ten years from the date of the grant or at such earlier time as the Option Agreement may provide; or

(B)                               More than 10% of the total combined voting power of all classes of stock of the Company or an Affiliate, each ISO shall terminate not more than five years from the date of the grant or at such earlier time as the Option Agreement may provide.

(iv)                              Limitation on Yearly Exercise: The Option Agreements shall restrict the amount of ISOs which may become exercisable in any calendar year (under this or any other ISO plan of the Company or an Affiliate) so that the aggregate Fair Market Value (determined on the date each ISO is granted) of the stock with respect to which ISOs are exercisable for the first time by the Participant in any calendar year does not exceed $100,000.

7.                                      TERMS AND CONDITIONS OF STOCK GRANTS.

Each Stock Grant to a Participant shall state the principal terms in an Agreement duly executed by the Company and, to the extent required by law or requested by the Company, by the Participant.  The Agreement shall be in a form approved by the Administrator and shall contain terms and conditions which the Administrator determines to be appropriate and in the best interest of the Company, subject to the following minimum standards:

(a)                                 Each Agreement shall state the purchase price per share, if any, of the Shares covered by each Stock Grant, which purchase price shall be determined by the Administrator but shall not be less than the minimum consideration required under applicable law, if any, on the date of the grant of the Stock Grant;

(b)                                 Each Agreement shall state the number of Shares to which the Stock Grant pertains; and

(c)                                  Each Agreement shall include the terms of any right of the Company to restrict or reacquire the Shares subject to the Stock Grant, including the time or attainment of Performance Goals upon which such rights shall accrue and the purchase price therefor, if any.

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8.                                      TERMS AND CONDITIONS OF OTHER STOCK-BASED AWARDS.

The Administrator shall have the right to grant other Stock-Based Awards based upon the Common Stock having such terms and conditions as the Administrator may determine, including, without limitation, the grant of Shares based upon certain conditions, the grant of securities convertible into Shares and the grant of stock appreciation rights, phantom stock awards or stock units.  The principal terms of each Stock-Based Award shall be set forth in an Agreement, duly executed by the Company and, to the extent required by law or requested by the Company, by the Participant.  The Agreement shall be in a form approved by the Administrator and shall contain terms and conditions which the Administrator determines to be appropriate and in the best interest of the Company.

The Company intends that the Plan and any Stock-Based Awards granted hereunder be exempt from the application of Section 409A of the Code or meet the requirements of paragraphs (2), (3) and (4) of subsection (a) of Section 409A of the Code, to the extent applicable, and be operated in accordance with Section 409A so that any compensation deferred under any Stock-Based Award (and applicable investment earnings) shall not be included in income under Section 409A of the Code.  Any ambiguities in the Plan shall be construed to effect the intent as described in this Paragraph 8.

9.                                      PERFORMANCE-BASED AWARDS.

A Participant’s Performance-Based Award shall be determined based on the attainment of written Performance Goals, which must be objective and approved by the Committee while the outcome for that performance period is substantially uncertain, and no more than ninety (90) days after the commencement of the performance period to which the Performance Goal relates or, if less, the number of days which is equal to twenty-five percent (25%) of the relevant performance period.  The Committee shall determine whether, with respect to a performance period, the applicable Performance Goals have been met with respect to a given Participant and, if they have, to so certify and ascertain the amount of the applicable Performance-Based Award.  No Performance-Based Awards will vest for such performance period until such certification is made by the Committee.  The number of Shares issued in respect of a Performance-Based Award to a given Participant may be less than the amount determined by the applicable Performance Goal formula, at the discretion of the Committee.

10.                               EXERCISE OF OPTIONS AND ISSUE OF SHARES.

An Option (or any part or installment thereof) shall be exercised by giving written notice to the Company or its designee (in a form acceptable to the Administrator, which may include electronic notice), together with provision for payment of the aggregate exercise price in accordance with this Paragraph 10 for the Shares as to which the Option is being exercised, and upon compliance with any other condition(s) set forth in the Option Agreement.  Such notice shall be signed by the person exercising the Option (which signature may be provided electronically in a form acceptable to the Administrator), shall state the number of Shares with respect to which the Option is being exercised and shall contain any representation required by the Plan or the Option Agreement.  Payment of the exercise price for the Shares as to which such Option is being exercised shall be made (a) in United States dollars in cash or by check, or (b) at the discretion of the Administrator, through delivery of shares of Common Stock held for at least six months (if required to avoid negative accounting treatment) having a Fair Market Value equal

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as of the date of the exercise to the aggregate cash exercise price for the number of Shares as to which the Option is being exercised, or (c) at the discretion of the Administrator, by having the Company retain from the Shares otherwise issuable upon exercise of the Option, a number of Shares having a Fair Market Value equal as of the date of exercise to the aggregate exercise price for the number of Shares as to which the Option is being exercised, or (d) at the discretion of the Administrator, in accordance with a cashless exercise program established with a securities brokerage firm, and approved by the Administrator, or (e) at the discretion of the Administrator, by any combination of (a), (b), (c) and (d) above or (f) at the discretion of the Administrator, by payment of such other lawful consideration as the Administrator may determine.  Notwithstanding the foregoing, the Administrator shall accept only such payment on exercise of an ISO as is permitted by Section 422 of the Code.

The Company shall then reasonably promptly deliver the Shares as to which such Option was exercised to the Participant (or to the Participant’s Survivors, as the case may be).  In determining what constitutes “reasonably promptly,” it is expressly understood that the issuance and delivery of the Shares may be delayed by the Company in order to comply with any law or regulation (including, without limitation, state securities or “blue sky” laws) which requires the Company to take any action with respect to the Shares prior to their issuance.  The Shares shall, upon delivery, be fully paid, non-assessable Shares.

The Administrator shall have the right to accelerate the date of exercise of any installment of any Option; provided that the Administrator shall not accelerate the exercise date of any installment of any Option granted to an Employee as an ISO (and not previously converted into a Non-Qualified Option pursuant to Paragraph 23) without the prior approval of the Employee if such acceleration would violate the annual vesting limitation contained in Section 422(d) of the Code, as described in Subclause 6(b)(iv).

The Administrator may, in its discretion, amend any term or condition of an outstanding Option provided (i) such term or condition as amended is permitted by the Plan, (ii) any such amendment shall be made only with the consent of the Participant to whom the Option was granted, or in the event of the death of the Participant, the Participant’s Survivors, if the amendment is adverse to the Participant, and (iii) any such amendment of any Option shall be made only after the Administrator determines whether such amendment would constitute a “modification” of any Option which is an ISO (as that term is defined in Section 424(h) of the Code) or would cause any adverse tax consequences for the holder of any Option including, but not limited to, pursuant to Section 409A of the Code.

11.                               ACCEPTANCE OF STOCK GRANTS AND STOCK-BASED AWARDS AND ISSUANCE OF SHARES.

A Stock Grant or Stock-Based Award (or any part or installment thereof) shall be accepted by executing the applicable Agreement and delivering it to the Company or its designee, together with provision for payment of the aggregate exercise price, if any, in accordance with this Paragraph 11 for the Shares as to which such Stock Grant or Stock-Based Award is being accepted, and upon compliance with any other conditions set forth in the applicable Agreement.  Payment of the purchase price for the Shares as to which such Stock Grant or Stock-Based Award is being accepted shall be made (a) in United States dollars in cash

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or by check, or (b) at the discretion of the Administrator, through delivery of shares of Common Stock held for at least six months (if required to avoid negative accounting treatment) and having a Fair Market Value equal as of the date of acceptance of the Stock Grant or Stock Based-Award to the purchase price of the Stock Grant or Stock-Based Award, or (c) at the discretion of the Administrator, by any combination of (a) and (b) above; or (d) at the discretion of the Administrator, by payment of such other lawful consideration as the Administrator may determine.

The Company shall then, if required by the applicable Agreement, reasonably promptly deliver the Shares as to which such Stock Grant or Stock-Based Award was accepted to the Participant (or to the Participant’s Survivors, as the case may be), subject to any escrow provision set forth in the applicable Agreement.  In determining what constitutes “reasonably promptly,” it is expressly understood that the issuance and delivery of the Shares may be delayed by the Company in order to comply with any law or regulation (including, without limitation, state securities or “blue sky” laws) which requires the Company to take any action with respect to the Shares prior to their issuance.

The Administrator may, in its discretion, amend any term or condition of an outstanding Stock Grant, Stock-Based Award or applicable Agreement provided (i) such term or condition as amended is permitted by the Plan, (ii) any such amendment shall be made only with the consent of the Participant to whom the Stock Grant or Stock-Based Award was made, if the amendment is adverse to the Participant, and (iii) any such amendment shall be made only after the Administrator determines whether such amendment would cause any adverse tax consequences to the Participant, including, but not limited to, pursuant to Section 409A of the Code.

12.                               RIGHTS AS A SHAREHOLDER.

No Participant to whom a Stock Right has been granted shall have rights as a shareholder with respect to any Shares covered by such Stock Right, except after due exercise of the Option or acceptance of the Stock Grant or as set forth in any Agreement, and tender of the aggregate exercise or purchase price, if any, for the Shares being purchased pursuant to such exercise or acceptance and registration of the Shares in the Company’s share register in the name of the Participant.

13.                               ASSIGNABILITY AND TRANSFERABILITY OF STOCK RIGHTS.

By its terms, a Stock Right granted to a Participant shall not be transferable by the Participant other than (a) by will or by the laws of descent and distribution, or (b) as approved by the Administrator in its discretion and set forth in the applicable Agreement provided that no Stock Right may be transferred by a Participant for value.  Notwithstanding the foregoing, an ISO transferred except in compliance with Subparagraph (a) above shall no longer qualify as an ISO.  The designation of a beneficiary of a Stock Right by a Participant, with the prior approval of the Administrator and in such form as the Administrator shall prescribe, shall not be deemed a transfer prohibited by this Paragraph 13.  Except as provided above, a Stock Right shall only be exercisable or may only be accepted, during the Participant’s lifetime, by such Participant (or by his or her legal representative) and shall not be assigned, pledged or hypothecated in any way (whether by operation of law or otherwise) and shall not be subject to execution, attachment or

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similar process.  Any attempted transfer, assignment, pledge, hypothecation or other disposition of any Stock Right or of any rights granted thereunder contrary to the provisions of this Plan, or the levy of any attachment or similar process upon a Stock Right, shall be null and void.

14.                               EFFECT ON OPTIONS OF TERMINATION OF SERVICE OTHER THAN FOR CAUSE OR DEATH OR DISABILITY.

Except as otherwise provided in a Participant’s Option Agreement, in the event of a termination of service (whether as an Employee, director or Consultant) with the Company or an Affiliate before the Participant has exercised an Option, the following rules apply:

(a)                                 A Participant who ceases to be an Employee, director or Consultant of the Company or of an Affiliate (for any reason other than termination for Cause, Disability, or death for which events there are special rules in Paragraphs 15, 16, and 17, respectively), may exercise any Option granted to him or her to the extent that the Option is exercisable on the date of such termination of service, but only within such term as the Administrator has designated in a Participant’s Option Agreement.

(b)                                 Except as provided in Subparagraph (c) below, or Paragraph 16 or 17, in no event may an Option intended to be an ISO, be exercised later than three months after the Participant’s termination of employment.

(c)                                  The provisions of this Subparagraph (c), and not the provisions of Paragraph 16 or 17, shall apply to a Participant who subsequently becomes Disabled or dies after the termination of employment, director status or consultancy; provided, however, in the case of a Participant’s Disability or death within three months after the termination of employment, director status or consultancy, the Participant or the Participant’s Survivors may exercise the Option within one year after the date of the Participant’s termination of service, but in no event after the date of expiration of the term of the Option.

(d)                                 Notwithstanding anything herein to the contrary, if subsequent to a Participant’s termination of employment, termination of director status or termination of consultancy, but prior to the exercise of an Option, the Administrator determines that, either prior or subsequent to the Participant’s termination, the Participant engaged in conduct which would constitute Cause, then such Participant shall forthwith cease to have any right to exercise any Option.

(e)                                  A Participant to whom an Option has been granted under the Plan who is absent from the Company or an Affiliate because of temporary disability (any disability other than a Disability as defined in Paragraph 1 hereof), or who is on leave of absence for any purpose, shall not, during the period of any such absence, be deemed, by virtue of such absence alone, to have terminated such Participant’s employment, director status or consultancy with the Company or with an Affiliate, except as the Administrator may otherwise expressly provide; provided, however, that, for ISOs, any leave of absence granted by the Administrator of greater than ninety days, unless pursuant to a contract or statute that guarantees the right to reemployment, shall cause such ISO to become a Non-Qualified Option on the 181st day following such leave of absence.

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(f)                                   Except as required by law or as set forth in a Participant’s Option Agreement, Options granted under the Plan shall not be affected by any change of a Participant’s status within or among the Company and any Affiliates, so long as the Participant continues to be an Employee, director or Consultant of the Company or any Affiliate.

15.                               EFFECT ON OPTIONS OF TERMINATION OF SERVICE FOR CAUSE.

Except as otherwise provided in a Participant’s Option Agreement, the following rules apply if the Participant’s service (whether as an Employee, director or Consultant) with the Company or an Affiliate is terminated for Cause prior to the time that all his or her outstanding Options have been exercised:

(a)                                 All outstanding and unexercised Options as of the time the Participant is notified that his or her service is terminated for Cause will immediately be forfeited.

(b)                                 Cause is not limited to events which have occurred prior to a Participant’s termination of service, nor is it necessary that the Administrator’s finding of Cause occur prior to termination.  If the Administrator determines, subsequent to a Participant’s termination of service but prior to the exercise of an Option, that either prior or subsequent to the Participant’s termination the Participant engaged in conduct which would constitute Cause, then the right to exercise any Option is forfeited.

16.                               EFFECT ON OPTIONS OF TERMINATION OF SERVICE FOR DISABILITY.

Except as otherwise provided in a Participant’s Option Agreement:

(a)                                 A Participant who ceases to be an Employee, director or Consultant of the Company or of an Affiliate by reason of Disability may exercise any Option granted to him or her to the extent that the Option has become exercisable but has not been exercised on the date of Disability.

(b)                                 A Disabled Participant may exercise the Option only within the period ending one year after the date of the Participant’s termination due to Disability, notwithstanding that the Participant might have been able to exercise the Option as to some or all of the Shares on a later date if the Participant had not become Disabled and had continued to be an Employee, director or Consultant or, if earlier, within the originally prescribed term of the Option.

(c)                                  The Administrator shall make the determination both of whether Disability has occurred and the date of its occurrence (unless a procedure for such determination is set forth in another agreement between the Company and such Participant, in which case such procedure shall be used for such determination).  If requested, the Participant shall be examined by a physician selected or approved by the Administrator, the cost of which examination shall be paid for by the Company.

17.                               EFFECT ON OPTIONS OF DEATH WHILE AN EMPLOYEE.  DIRECTOR OR CONSULTANT.

Except as otherwise provided in a Participant’s Option Agreement:

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(a)                                 In the event of the death of a Participant while the Participant is an Employee, director or Consultant of the Company or of an Affiliate, such Option may be exercised by the Participant’s Survivors to the extent that the Option has become exercisable but has not been exercised on the date of death.

(b)                                 If the Participant’s Survivors wish to exercise the Option, they must take all necessary steps to exercise the Option within one year after the date of death of such Participant, notwithstanding that the decedent might have been able to exercise the Option as to some or all of the Shares on a later date if he or she had not died and had continued to be an Employee, director or Consultant or, if earlier, within the originally prescribed term of the Option.

18.                               PURCHASE FOR INVESTMENT.

Unless the offering and sale of the Shares to be issued upon the particular exercise or acceptance of a Stock Right shall have been effectively registered under the Securities Act, the Company shall be under no obligation to issue the Shares covered by such exercise unless and until the following conditions have been fulfilled:

(a)                                 The person who exercises or accepts such Stock Right shall warrant to the Company, prior to the receipt of such Shares, that such person is acquiring such Shares for his or her own account, for investment, and not with a view to, or for sale in connection with, the distribution of any such Shares, in which event the person acquiring such Shares shall be bound by the provisions of the following legend (or a legend in substantially similar form) which shall be endorsed upon the certificate evidencing the Shares issued pursuant to such exercise or such grant:

“The shares represented by this certificate have been taken for investment and they may not be sold or otherwise transferred by any person, including a pledgee, unless (1) either (a) a Registration Statement with respect to such shares shall be effective under the Securities Act of 1933, as amended, or (b) the Company shall have received an opinion of counsel satisfactory to it that an exemption from registration under such Act is then available, and (2) there shall have been compliance with all applicable state securities laws.”

(b)                                 At the discretion of the Administrator, the Company shall have received an opinion of its counsel that the Shares may be issued upon such particular exercise or acceptance in compliance with the Securities Act without registration thereunder.

19.                               DISSOLUTION OR LIQUIDATION OF THE COMPANY.

Upon the dissolution or liquidation of the Company, all Options granted under this Plan which as of such date shall not have been exercised and all Stock Grants and Stock-Based Awards which have not been accepted will terminate and become null and void; provided, however, that if the rights of a Participant or a Participant’s Survivors have not otherwise terminated and expired, the Participant or the Participant’s Survivors will have the right immediately prior to such dissolution or liquidation to exercise or accept any Stock Right to the extent that the Stock Right is exercisable or subject to acceptance as of the date immediately prior to such dissolution or liquidation.  Upon the dissolution or liquidation of the Company, any

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outstanding Stock-Based Awards shall immediately terminate unless otherwise determined by the Administrator or specifically provided in the applicable Agreement.

20.                               ADJUSTMENTS.

Upon the occurrence of any of the following events, a Participant’s rights with respect to any Stock Right granted to him or her hereunder shall be adjusted as hereinafter provided, unless otherwise specifically provided in a Participant’s Agreement:

(a)                                 Stock Dividends and Stock Splits.  If (i) the shares of Common Stock shall be subdivided or combined into a greater or smaller number of shares or if the Company shall issue any shares of Common Stock as a stock dividend on its outstanding Common Stock, or additional shares or new or different shares or other securities of the Company or other non- cash assets are distributed with respect to such shares of Common Stock, each Stock Right and the number of shares of Common Stock deliverable thereunder shall be appropriately increased or decreased proportionately, and appropriate adjustments shall be made including, in the exercise or purchase price per share, to reflect such events.  The number of Shares subject to the limitations in Subparagraphs 3(a) and 4(c) shall also be proportionately adjusted upon the occurrence of such events.

(b)                                 Corporate Transactions.  If the Company is to be consolidated with or acquired by another entity in a merger, consolidation, or sale of all or substantially all of the Company’s assets other than a transaction to merely change the state of incorporation (a “Corporate Transaction”), the Administrator or the board of directors of any entity assuming the obligations of the Company hereunder (the “Successor Board”), shall, as to outstanding Options, either (i) make appropriate provision for the continuation of such Options by substituting on an equitable basis for the Shares then subject to such Options either the consideration payable with respect to the outstanding shares of Common Stock in connection with the Corporate Transaction or securities of any successor or acquiring entity; or (ii) upon written notice to the Participants, provide that such Options must be exercised (any such Options being made fully exercisable for purposes of this Subparagraph (b)), within a specified number of days of the date of such notice, at the end of which period such Options which have not been exercised shall terminate; or (iii) terminate such Options in exchange for payment of an amount equal to the consideration payable upon consummation of such Corporate Transaction to a holder of the number of shares of Common Stock into which such Option would have been exercisable (any such Options being made fully exercisable for purposes of this Subparagraph (b)) less the aggregate exercise price thereof.  For purposes of determining the payments to be made pursuant to Subclause (iii) above, in the case of a Corporate Transaction the consideration for which, in whole or in part, is other than cash, the consideration other than cash shall be valued at the fair value thereof as determined in good faith by the Board of Directors.

With respect to outstanding Stock Grants, the Administrator or the Successor Board, shall make appropriate provision for the continuation of such Stock Grants on the same terms and conditions by substituting on an equitable basis for the Shares then subject to such Stock Grants either the consideration payable with respect to the outstanding Shares of Common Stock in connection with the Corporate Transaction or securities of any successor or acquiring entity.  In lieu of the foregoing, in connection with any Corporate Transaction, the Administrator may

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provide that, upon consummation of the Corporate Transaction, each outstanding Stock Grant shall be terminated in exchange for payment of an amount equal to the consideration payable upon consummation of such Corporate Transaction to a holder of the number of shares of Common Stock comprising such Stock Grant.

In taking any of the actions permitted under this Subparagraph 20(b), the Administrator shall not be obligated by the Plan to treat all Stock Rights, all Stock Rights held by a Participant, or all Stock Rights of the same type, identically.

(c)                                  Recapitalization or Reorganization.  In the event of a recapitalization or reorganization of the Company other than a Corporate Transaction pursuant to which securities of the Company or of another corporation are issued with respect to the outstanding shares of Common Stock, a Participant upon exercising an Option or accepting a Stock Grant after the recapitalization or reorganization shall be entitled to receive for the price paid upon such exercise or acceptance if any, the number of replacement securities which would have been received if such Option had been exercised or Stock Grant accepted prior to such recapitalization or reorganization.

(d)                                 Adjustments to Stock-Based Awards.  Upon the happening of any of the events described in Subparagraphs (a), (b) or (c) above, any outstanding Stock-Based Award shall be appropriately adjusted to reflect the events described in such Subparagraphs.  The Administrator or the Successor Board shall determine the specific adjustments to be made under this Paragraph 20, including, but not limited to the effect of any, Corporate Transaction and, subject to Paragraph 4, its determination shall be conclusive.  Except as permitted in this Subparagraph 20(d), the Administrator may not, without obtaining stockholder approval: (a) amend the terms of any outstanding Stock-Based Award to reduce the exercise price of such Stock-Based Award; (b) cancel any outstanding Stock-Based Award in exchange for an Option or Stock-Based Award with an exercise price that is less than the exercise price of the original Stock-Based Award; or (c) cancel any outstanding Stock-Based Award with an exercise price above the current stock price in exchange for cash or other securities.

(e)                                  Modification of Options.  Notwithstanding the foregoing, any adjustments made pursuant to Subparagraph (a), (b) or (c) above with respect to Options shall be made only after the Administrator determines whether such adjustments would constitute a “modification” of any ISOs (as that term is defined in Section 424(h) of the Code) or would cause any adverse tax consequences for the holders of Options, including, but not limited to, pursuant to Section 409A of the Code.  If the Administrator determines that such adjustments made with respect to Options would constitute a modification or other adverse tax consequence, it may refrain from making such adjustments, unless the holder of an Option specifically agrees in writing that such adjustment be made and such writing indicates that the holder has full knowledge of the consequences of such “modification” on his or her income tax treatment with respect to the Option.  This Subparagraph (e) shall not apply to the acceleration of the vesting of any ISO that would cause any portion of the ISO to violate the annual vesting limitation contained in Section 422(d) of the Code, as described in Subclause 6(b)(iv).

Except as permitted in this Subparagraph 20(e), the Administrator may not, without obtaining stockholder approval: (a) amend the terms of any outstanding Option to reduce the

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exercise price of such Option; (b) cancel any outstanding Option in exchange for an Option or Stock-Based Award with an exercise price that is less than the exercise price of the original Option; or (c) cancel any outstanding Option with an exercise price above the current stock price in exchange for cash or other securities.

(f)                                   Modification of Performance-Based Awards.  Notwithstanding the foregoing, with respect to any Performance-Based Award that is intended to comply as “performance based compensation” under Section 162(m) of the Code, the Committee may adjust proportionately the number of Shares payable pursuant to a Performance-Based Award to reflect the Corporate Transaction or other event but may not otherwise increase the number of Shares, and the Committee may not waive the achievement of the applicable Performance Goals except in the case of death or Disability of the Participant or in connection with a Corporate Transaction.

21.                               ISSUANCES OF SECURITIES.

Except as expressly provided herein, no issuance by the Company of shares of stock of any class, or securities convertible into shares of stock of any class, shall affect, and no adjustment by reason thereof shall be made with respect to, the number or price of shares subject to Stock Rights.  Except as expressly provided herein, no adjustments shall be made for dividends paid in cash or in property (including without limitation, securities) of the Company prior to any issuance of Shares pursuant to a Stock Right.

22.                               FRACTIONAL SHARES.

No fractional shares shall be issued under the Plan and the person exercising a Stock Right shall receive from the Company cash in lieu of such fractional shares equal to the Fair Market Value thereof.

23.                               CONVERSION OF ISOS INTO NON-QUALIFIED OPTIONS; TERMINATION OF ISOS.

The Administrator, at the written request of any Participant, may in its discretion take such actions as may be necessary to convert such Participant’s ISOs (or any portions thereof) that have not been exercised on the date of conversion into Non-Qualified Options at any time prior to the expiration of such ISOs, regardless of whether the Participant is an Employee of the Company or an Affiliate at the time of such conversion.  At the time of such conversion, the Administrator (with the consent of the Participant) may impose such conditions on the exercise of the resulting Non-Qualified Options as the Administrator in its discretion may determine, provided that such conditions shall not be inconsistent with this Plan.  Nothing in the Plan shall be deemed to give any Participant the right to have such Participant’s ISOs converted into Non-Qualified Options, and no such conversion shall occur until and unless the Administrator takes appropriate action.  The Administrator, with the consent of the Participant, may also terminate any portion of any ISO that has not been exercised at the time of such conversion.

24.                               WITHHOLDING.

In the event that any federal, state, or local income taxes, employment taxes, Federal Insurance Contributions Act withholdings or other amounts are required by applicable law or

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governmental regulation to be withheld from the Participant’s salary, wages or other remuneration in connection with the exercise or acceptance of a Stock Right or in connection with a Disqualifying Disposition (as defined in Paragraph 25) or upon the lapsing of any forfeiture provision or right of repurchase or for any other reason required by law, the Company may withhold from the Participant’s compensation, if any, or may require that the Participant advance in cash to the Company, or to any Affiliate of the Company which employs or employed the Participant, the statutory minimum amount of such withholdings unless a different withholding arrangement, including the use of shares of the Company’s Common Stock, is authorized by the Administrator (and permitted by law).  For purposes hereof, the fair market value of the shares withheld for purposes of payroll withholding shall be determined in the manner set forth under the definition of Fair Market Value provided in Paragraph 1 above, as of the most recent practicable date prior to the date of exercise.  If the Fair Market Value of the shares withheld is less than the amount of payroll withholdings required, the Participant may be required to advance the difference in cash to the Company or the Affiliate employer.  The Administrator in its discretion may condition the exercise of an Option for less than the then Fair Market Value on the Participant’s payment of such additional withholding.

25.                               NOTICE TO COMPANY OF DISQUALIFYING DISPOSITION.

Each Employee who receives an ISO must agree to notify the Company in writing immediately after the Employee makes a Disqualifying Disposition of any Shares acquired pursuant to the exercise of an ISO.  A Disqualifying Disposition is defined in Section 424(c) of the Code and includes any disposition (including any sale or gift) of such Shares before the later of (a) two years after the date the Employee was granted the ISO, or (b) one year after the date the Employee acquired Shares by exercising the ISO, except as otherwise provided in Section 424(c) of the Code.  If the Employee has died before such Shares are sold, these holding period requirements do not apply and no Disqualifying Disposition can occur thereafter.

26.                               TERMINATION OF THE PLAN.

The Plan will terminate on December 17, 2019.  The Plan may be terminated at an earlier date by vote of the shareholders or the Board of Directors of the Company; provided, however, that any such earlier termination shall not affect any Agreements executed prior to the effective date of such termination.  Termination of the Plan shall not affect any Stock Rights theretofore granted.

27.                               AMENDMENT OF THE PLAN AND AGREEMENTS.

The Plan may be amended by the shareholders of the Company.  The Plan may also be amended by the Administrator, including, without limitation, to the extent necessary to qualify any or all outstanding Stock Rights granted under the Plan or Stock Rights to be granted under the Plan for favorable federal income tax treatment as may be afforded incentive stock options under Section 422 of the Code (including deferral of taxation upon exercise); to the extent necessary to qualify the shares issuable upon exercise or acceptance of any outstanding Stock Rights granted, or Stock Rights to be granted, under the Plan for listing on any national securities exchange or quotation in any national automated quotation system of securities dealers; and, in order to continue to comply with Section 162(m) of the Code.  Any amendment approved by the

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Administrator which the Administrator determines is of a scope that requires shareholder approval shall be subject to obtaining such shareholder approval.  Any modification or amendment of the Plan shall not, without the consent of a Participant, adversely affect his or her rights under a Stock Right previously granted to him or her.  With the consent of the Participant affected, the Administrator may amend outstanding Agreements in a manner which may be adverse to the Participant but which is not inconsistent with the Plan.  In the discretion of the Administrator, outstanding Agreements may be amended by the Administrator in a manner which is not adverse to the Participant.

28.                               EMPLOYMENT OR OTHER RELATIONSHIP.

Nothing in this Plan or any Agreement shall be deemed to prevent the Company or an Affiliate from terminating the employment, consultancy or director status of a Participant, nor to prevent a Participant from terminating his or her own employment, consultancy or director status or to give any Participant a right to be retained in employment or other service by the Company or any Affiliate for any period of time.

29.                               GOVERNING LAW.

This Plan shall be construed and enforced in accordance with the laws of the Commonwealth of Massachusetts.

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Exhibit 4.6

CYCLERION THERAPEUTICS, INC.

AMENDED AND RESTATED 2005 STOCK INCENTIVE PLAN

1.             Purpose

The purpose of this Amended and Restated 2005 Stock Incentive Plan (the “Plan”) of Cyclerion Therapeutics, Inc., a Massachusetts corporation (the “Company”), is to advance the interests of the Company’s stockholders by enhancing the Company’s ability to attract, retain and motivate persons who are expected to make important contributions to the Company and by providing such persons with equity ownership opportunities and performance-based incentives that are intended to align their interests with those of the Company’s stockholders. Except where the context otherwise requires, the term “Company” shall include any of the Company’s present or future parent or subsidiary corporations as defined in Sections 424(e) or (f) of the Internal Revenue Code of 1986, as amended, and any regulations promulgated thereunder (the “Code”) and any other business venture (including, without limitation, joint venture or limited liability company) in which the Company has a controlling interest, as determined by the Board of Directors of the Company (the “Board”). The Plan has been adopted by the Board solely for the purpose of granting Awards in respect of equity-based awards previously granted under the Ironwood Pharmaceuticals, Inc. Amended and Restated 2005 Stock Incentive Plan (the “Ironwood 2005 Plan”) and converted into equity-based awards of the Company pursuant to Article 5 of the Employee Matters Agreement by and between Ironwood Pharmaceuticals, Inc. and the Company dated as of March 30, 2019 (the “Employee Matters Agreement”). The Plan is intended to mirror in all material respects the terms and conditions of the Ironwood 2005 Plan (other than those terms that are made inoperative by the separation of the Company’s soluble guanylate cyclase business from Ironwood Pharmaceuticals, Inc.)

2.             Eligibility

All employees, officers, directors, consultants and advisors of the Company and Ironwood Pharmaceuticals, Inc. who were granted options, restricted stock, restricted stock units and other stock-based awards (each, an “Award”) under the Plan prior to the separation of the Company from Ironwood Pharmaceuticals, Inc., are eligible to participate in the Plan. Each person who receives an Award under the Plan is deemed a “Participant”.

3.             Administration and Delegation

(a)           Administration by Board of Directors. The Plan will be administered by the Board. The Board shall have authority to grant Awards and to adopt, amend and repeal such administrative rules, guidelines and practices relating to the Plan as it shall deem advisable. The Board may correct any defect, supply any omission or reconcile any inconsistency in the Plan or any Award in the manner and to the extent it shall deem expedient to carry the Plan into effect and it shall be the sole and final judge of such expediency. All decisions by the Board shall be made in the Board’s sole discretion and shall be final and binding on all persons having or claiming any interest in the Plan or in any Award. No director or person acting pursuant to the authority delegated by

the Board shall be liable for any action or determination relating to or under the Plan made in good faith.

(b)           Appointment of Committees. To the extent permitted by applicable law, the Board may delegate any or all of its powers under the Plan to one or more committees or subcommittees of the Board (a “Committee”). All references in the Plan to the “Board” shall mean the Board or a Committee of the Board to the extent that the Board’s powers or authority under the Plan have been delegated to such Committee.

4.             Stock Available for Awards. Subject to adjustment under Section 8, Awards may be made under the Plan for up to the lesser of (i) 350,000 shares of common stock of the Company (the “Common Stock”) and (ii) that number of shares of Common Stock necessary to give effect to the grant of equity-based awards contemplated by Article 5 of the Employee Matters Agreement.  Any shares of Common Stock underlying Awards that are forfeited, expired or are cancelled without the delivery of shares of Common Stock thereunder, shall be added to the number of shares of Common Stock that may be issued in satisfaction of awards under the Company’s 2019 Equity Incentive Plan.

5.             Stock Options

(a)           General. The Board may grant options to purchase Common Stock (each, an “Option”), and determine the number of shares of Common Stock to be covered by each Option, the exercise price of each Option and the conditions and limitations applicable to the exercise of each Option, including conditions relating to applicable federal or state securities laws, as it considers necessary or advisable. An Option which is not intended to be an Incentive Stock Option (as hereinafter defined) shall be designated a “Nonstatutory Stock Option”.

(b)           Incentive Stock Options. An Option that the Board intends to be an “incentive stock option” as defined in Section 422 of the Code (an “Incentive Stock Option”) shall only be granted to employees of the Company, any of the Company’s present or future parent or subsidiary corporations as defined in Sections 424(e) or (f) of the Code, and any other entities the employees of which are eligible to receive Incentive Stock Options under the Code, and shall be subject to and shall be construed consistently with the requirements of Section 422 of the Code. The Company shall have no liability to a Participant, or any other party, if an Option (or any part thereof) that is intended to be an Incentive Stock Option is not an Incentive Stock Option or for any action taken by the Board pursuant to Section 9(f), including without limitation the conversion of an Incentive Stock Option to a Nonstatutory Stock Option.

(c)           Exercise Price. The Board shall establish the exercise price of each Option and specify such exercise price in the applicable option agreement.

(d)           Duration of Options. Each Option shall be exercisable at such times and subject to such terms and conditions as the Board may specify in the applicable option agreement.

(e)           Exercise of Option. Options may be exercised by delivery to the Company of a written notice of exercise signed by the proper person or by any other form of notice (including electronic notice) approved by the Board together with payment in full as specified in Section 5(f) for the number of shares for which the Option is exercised. Shares of Common Stock subject to

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the Option will be delivered by the Company following exercise either as soon as practicable or, subject to such conditions as the Board shall specify, on a deferred basis (with the Company’s obligation to be evidenced by an instrument providing for future delivery of the deferred shares at the time or times specified by the Board).

(f)            Payment Upon Exercise. Common Stock purchased upon the exercise of an Option granted under the Plan shall be paid for as follows:

(1)           in cash or by check, payable to the order of the Company;

(2)           except as the Board may otherwise provide in an option agreement, by (i) delivery of an irrevocable and unconditional undertaking by a creditworthy broker to deliver promptly to the Company sufficient funds to pay the exercise price and any required tax withholding or (ii) delivery by the Participant to the Company of a copy of irrevocable and unconditional instructions to a creditworthy broker to deliver promptly to the Company cash or a check sufficient to pay the exercise price and any required tax withholding;

(3)           by delivery of shares of Common Stock owned by the Participant valued at their fair market value as determined by (or in a manner approved by) the Board (“Fair Market Value”), provided (i) such method of payment is then permitted under applicable law, (ii) such Common Stock, if acquired directly from the Company, was owned by the Participant for such minimum period of time, if any, as may be established by the Board in its discretion and (iii) such Common Stock is not subject to any repurchase, forfeiture, unfulfilled vesting or other similar requirements;

(4)           to the extent permitted by applicable law and by the Board, by (i) delivery of a promissory note of the Participant to the Company on terms determined by the Board, or (ii) payment of such other lawful consideration as the Board may determine; or

(5)           by any combination of the above permitted forms of payment.

(g)           Substitute Options. In connection with a merger or consolidation of an entity with the Company or the acquisition by the Company of property or stock of an entity, the Board may grant Options in substitution for any options or other stock or stock-based awards granted by such entity or an affiliate thereof. Substitute Options may be granted on such terms as the Board deems appropriate in the circumstances, notwithstanding any limitations on Options contained in the other sections of this Section 5 or in Section 2. Substitute Options shall not count against the overall share limit set forth in Section 4(a), except as may be required by reason of Section 422 and related provisions of the Code.

6.             Restricted Stock; Restricted Stock Units

(a)           General. The Board may grant Awards entitling recipients to acquire shares of Common Stock (“Restricted Stock”), subject to the right of the Company to repurchase all or part of such shares at their issue price or other stated or formula price (or to require forfeiture of such shares if issued at no cost) from the recipient in the event that conditions specified by the Board in the applicable Award are not satisfied prior to the end of the applicable restriction period or periods established by the Board for such Award. Instead of granting Awards for Restricted Stock, the

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Board may grant Awards entitling the recipient to receive shares of Common Stock to be delivered at the time such shares of Common Stock vest (“Restricted Stock Units”) (Restricted Stock and Restricted Stock Units are each referred to herein as a “Restricted Stock Award”).

(b)           Terms and Conditions. The Board shall determine the terms and conditions of a Restricted Stock Award, including the conditions for repurchase (or forfeiture) and the issue price, if any.

(c)           Stock Certificates. Any stock certificates issued in respect of a Restricted Stock Award shall be registered in the name of the Participant and, unless otherwise determined by the Board, deposited by the Participant, together with a stock power endorsed in blank, with the Company (or its designee). At the expiration of the applicable restriction periods, the Company (or such designee) shall deliver the certificates no longer subject to such restrictions to the Participant or if the Participant has died, to the beneficiary designated, in a manner determined by the Board, by a Participant to receive amounts due or exercise rights of the Participant in the event of the Participant’s death (the “Designated Beneficiary”). In the absence of an effective designation by a Participant, “Designated Beneficiary” shall mean the Participant’s estate.

7.             Other Stock-Based Awards

Other Awards of shares of Common Stock, and other Awards that are valued in whole or in part by reference to, or are otherwise based on, shares of Common Stock or other property, may be granted hereunder to Participants (“Other Stock Unit Awards”), including without limitation stock appreciation rights and Awards entitling recipients to receive shares of Common Stock to be delivered in the future. Such Other Stock Unit Awards shall also be available as a form of payment in the settlement of other Awards granted under the Plan or as payment in lieu of compensation to which a Participant is otherwise entitled. Other Stock Unit Awards may be paid in shares of Common Stock or cash, as the Board shall determine. Subject to the provisions of the Plan, the Board shall determine the conditions of each Other Stock Unit Award, including any purchase price applicable thereto.

8.             Adjustments for Changes in Common Stock and Certain Other Events

(a)           Changes in Capitalization. In the event of any stock split, reverse stock split, stock dividend, recapitalization, combination of shares, reclassification of shares, spin-off or other similar change in capitalization or event, or any distribution to holders of Common Stock other than an ordinary cash dividend, (i) the number and class of securities available under this Plan, (ii) the number and class of securities and exercise price per share of each outstanding Option, (iii) the repurchase price per share subject to each outstanding Restricted Stock Award, and (iv) the terms of each other outstanding Award shall be appropriately adjusted by the Company (or substituted Awards may be made, if applicable) to the extent determined by the Board.

(b)           Reorganization Events

(1)           Definition. A “Reorganization Event” shall mean: (a) any merger or consolidation of the Company with or into another entity as a result of which all of the Common Stock of the Company is converted into or exchanged for the right to receive cash, securities or other property or is cancelled, (b) any exchange of all of the Common Stock of the Company for

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cash, securities or other property pursuant to a share exchange transaction or (c) any liquidation or dissolution of the Company.

(2)           Consequences of a Reorganization Event on Awards Other than Restricted Stock Awards. In connection with a Reorganization Event, the Board shall take any one or more of the following actions as to all or any outstanding Awards on such terms as the Board determines: (i) provide that Awards shall be assumed, or substantially equivalent Awards shall be substituted, by the acquiring or succeeding corporation (or an affiliate thereof), (ii) upon written notice to a Participant, provide that the Participant’s unexercised Options or other unexercised Awards shall become exercisable in full and will terminate immediately prior to the consummation of such Reorganization Event unless exercised by the Participant within a specified period following the date of such notice, (iii) provide that outstanding Awards shall become realizable or deliverable, or restrictions applicable to an Award shall lapse, in whole or in part prior to or upon such Reorganization Event, (iv) in the event of a Reorganization Event under the terms of which holders of Common Stock will receive upon consummation thereof a cash payment for each share surrendered in the Reorganization Event (the “Acquisition Price”), make or provide for a cash payment to a Participant equal to (A) the Acquisition Price times the number of shares of Common Stock subject to the Participant’s Options or other Awards (to the extent the exercise price does not exceed the Acquisition Price) minus (B) the aggregate exercise price of all such outstanding Options or other Awards, in exchange for the termination of such Options or other Awards, (v) provide that, in connection with a liquidation or dissolution of the Company, Awards shall convert into the right to receive liquidation proceeds (if applicable, net of the exercise price thereof) and (vi) any combination of the foregoing.

For purposes of clause (i) above, an Option shall be considered assumed if, following consummation of the Reorganization Event, the Option confers the right to purchase, for each share of Common Stock subject to the Option immediately prior to the consummation of the Reorganization Event, the consideration (whether cash, securities or other property) received as a result of the Reorganization Event by holders of Common Stock for each share of Common Stock held immediately prior to the consummation of the Reorganization Event (and if holders were offered a choice of consideration, the type of consideration chosen by the holders of a majority of the outstanding shares of Common Stock); provided, however, that if the consideration received as a result of the Reorganization Event is not solely common stock of the acquiring or succeeding corporation (or an affiliate thereof), the Company may, with the consent of the acquiring or succeeding corporation, provide for the consideration to be received upon the exercise of Options to consist solely of common stock of the acquiring or succeeding corporation (or an affiliate thereof) equivalent value (as determined by the Board) to the per share consideration received by holders of outstanding shares of Common Stock as a result of the Reorganization Event. Notwithstanding the foregoing, for purposes of clause (i) above, in the event of a merger or consolidation of the Company (a) effected to reincorporate the Company outside of Massachusetts or (b) with or into a wholly-owned subsidiary of the Company (each of (a) and (b), an “Excluded Event”), an Option shall be considered assumed if following consummation of the Excluded Event, the Option confers the right to purchase, for each share of Common Stock subject to the Option immediately prior to the consummation of the Reorganization Event, the consideration (whether cash, securities or other property) received as a result of the Excluded Event by holders of such Common Stock for each share of such Common Stock held immediately prior to the consummation of the Excluded Event (and if holders were offered a choice of consideration, the type of

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consideration chosen by the holders of a majority of the outstanding shares of such Common Stock); provided, however, that if the consideration received as a result of the Excluded Event is not solely common stock of the acquiring or succeeding corporation (or an affiliate thereof), the Company may, with the consent of the acquiring or succeeding corporation, provide for the consideration to be received upon the exercise of Options to consist solely of common stock of the acquiring or succeeding corporation (or an affiliate thereof) equivalent value (as determined by the Board) to the per share consideration received by holders of outstanding shares of Common Stock as a result of the Excluded Event.

To the extent all or any portion of an Option becomes exercisable solely as a result of clause (ii) above, the Board may provide that upon exercise of such Option the Participant shall receive shares subject to a right of repurchase by the Company or its successor at the Option exercise price; such repurchase right (x) shall lapse at the same rate as the Option would have become exercisable under its terms and (y) shall not apply to any shares subject to the Option that were exercisable under its terms without regard to clause (ii) above.

(3)           Consequences of a Reorganization Event on Restricted Stock Awards. Upon the occurrence of a Reorganization Event other than a liquidation or dissolution of the Company, the repurchase and other rights of the Company under each outstanding Restricted Stock Award shall inure to the benefit of the Company’s successor and shall apply to the cash, securities or other property which the Common Stock was converted into or exchanged for pursuant to such Reorganization Event in the same manner and to the same extent as they applied to the Common Stock subject to such Restricted Stock Award. Upon the occurrence of a Reorganization Event involving the liquidation or dissolution of the Company, except to the extent specifically provided to the contrary in the instrument evidencing any Restricted Stock Award or any other agreement between a Participant and the Company, all restrictions and conditions on all Restricted Stock Awards then outstanding shall automatically be deemed terminated or satisfied.

9.             General Provisions Applicable to Awards

(a)           Transferability of Awards. Except as the Board may otherwise determine or provide in an Award, Awards shall not be sold, assigned, transferred, pledged or otherwise encumbered by the person to whom they are granted, either voluntarily or by operation of law, except by will or the laws of descent and distribution or, other than in the case of an Incentive Stock Option, pursuant to a qualified domestic relations order, and, during the life of the Participant, shall be exercisable only by the Participant. References to a Participant, to the extent relevant in the context, shall include references to authorized transferees.

(b)           Documentation. Each Award shall be evidenced in such form (written, electronic or otherwise) as the Board shall determine. Each Award may contain terms and conditions in addition to those set forth in the Plan.

(c)           Board Discretion. Except as otherwise provided by the Plan, each Award may be made alone or in addition or in relation to any other Award. The terms of each Award need not be identical, and the Board need not treat Participants uniformly.

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(d)           Termination of Status. The Board shall determine the effect on an Award of the disability, death, retirement, authorized leave of absence or other change in the employment or other status of a Participant and the extent to which, and the period during which, the Participant, or the Participant’s legal representative, conservator, guardian or Designated Beneficiary, may exercise rights under the Award.

(e)           Withholding. Each Participant shall pay to the Company, or make provision satisfactory to the Company for payment of, any taxes required by law to be withheld in connection with an Award to such Participant. Except as the Board may otherwise provide in an Award, for so long as the Common Stock is registered under the Exchange Act, Participants may satisfy such tax obligations in whole or in part by delivery of shares of Common Stock, including shares retained from the Award creating the tax obligation, valued at their Fair Market Value; provided, however, except as otherwise provided by the Board, that the total tax withholding where stock is being used to satisfy such tax obligations cannot exceed the Company’s minimum statutory withholding obligations (based on minimum statutory withholding rates for federal and state tax purposes, including payroll taxes, that are applicable to such supplemental taxable income). Shares surrendered to satisfy tax withholding requirements cannot be subject to any repurchase, forfeiture, unfulfilled vesting or other similar requirements. The Company may, to the extent permitted by law, deduct any such tax obligations from any payment of any kind otherwise due to a Participant.

(f)            Amendment of Award. The Board may amend, modify or terminate any outstanding Award, including but not limited to, substituting therefor another Award of the same or a different type, changing the date of exercise or realization, and converting an Incentive Stock Option to a Nonstatutory Stock Option, provided that the Participant’s consent to such action shall be required unless the Board determines that the action, taking into account any related action, would not materially and adversely affect the Participant.

(g)           Conditions on Delivery of Stock. The Company will not be obligated to deliver any shares of Common Stock pursuant to the Plan or to remove restrictions from shares previously delivered under the Plan until (i) all conditions of the Award have been met or removed to the satisfaction of the Company, (ii) in the opinion of the Company’s counsel, all other legal matters in connection with the issuance and delivery of such shares have been satisfied, including any applicable securities laws and any applicable stock exchange or stock market rules and regulations, and (iii) the Participant has executed and delivered to the Company such representations or agreements as the Company may consider appropriate to satisfy the requirements of any applicable laws, rules or regulations.

(h)           Acceleration. The Board may at any time provide that any Award shall become immediately exercisable in full or in part, free of some or all restrictions or conditions, or otherwise realizable in full or in part, as the case may be.

10.          Miscellaneous

(a)           No Right To Employment or Other Status. No person shall have any claim or right to be granted an Award, and the grant of an Award shall not be construed as giving a Participant the right to new or continued employment or any other relationship with the Company. The Company expressly reserves the right at any time to dismiss or otherwise terminate its relationship

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with a Participant free from any liability or claim under the Plan, except as expressly provided in the applicable Award.

(b)           No Rights As Stockholder. Subject to the provisions of the applicable Award, no Participant or Designated Beneficiary shall have any rights as a stockholder with respect to any shares of Common Stock to be distributed with respect to an Award until becoming the record holder of such shares. Notwithstanding the foregoing, in the event the Company effects a split of the Common Stock by means of a stock dividend and the exercise price of and the number of shares subject to such Option are adjusted as of the date of the distribution of the dividend (rather than as of the record date for such dividend), then an optionee who exercises an Option between the record date and the distribution date for such stock dividend shall be entitled to receive, on the distribution date, the stock dividend with respect to the shares of Common Stock acquired upon such Option exercise, notwithstanding the fact that such shares were not outstanding as of the close of business on the record date for such stock dividend.

(c)           Effective Date and Term of Plan. The Plan shall become effective on the date on which it is adopted by the Board. No Awards shall be granted under the Plan after the completion of 10 years from the earlier of (i) the date on which the Plan was adopted by the Board or (ii) the date the Plan was approved by the Company’s stockholders, but Awards previously granted may extend beyond that date. For the avoidance of doubt, no Awards shall be granted under the Plan except in accordance with Article 5 of the Employee Matters Agreement.

(d)           Amendment of Plan. The Board may amend, suspend or terminate the Plan or any portion thereof at any time.

(e)           Authorization of Sub-Plans. The Board may from time to time establish one or more sub-plans under the Plan for purposes of satisfying applicable blue sky, securities or tax laws of various jurisdictions. The Board shall establish such sub-plans by adopting supplements to this Plan containing (i) such limitations on the Board’s discretion under the Plan as the Board deems necessary or desirable or (ii) such additional terms and conditions not otherwise inconsistent with the Plan as the Board shall deem necessary or desirable. All supplements adopted by the Board shall be deemed to be part of the Plan, but each supplement shall apply only to Participants within the affected jurisdiction and the Company shall not be required to provide copies of any supplement to Participants in any jurisdiction which is not the subject of such supplement.

(f)            Compliance with Code Section 409A. No Award shall provide for deferral of compensation that does not comply with Section 409A of the Code, unless the Board, at the time of grant, specifically provides that the Award is not intended to comply with Section 409A of the Code.

(g)           Governing Law. The provisions of the Plan and all Awards made hereunder shall be governed by and interpreted in accordance with the laws of the State of Massachusetts, excluding choice-of-law principles of the law of such state that would require the application of the laws of a jurisdiction other than such state.

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ATTACHMENT I

CYCLERION THERAPEUTICS, INC.

Incentive Stock Option Agreement
Granted under Amended and Restated 2005 Stock Incentive Plan

1.                                      Grant of Option.

This agreement evidences the grant by Cyclerion Therapeutics, Inc., a Massachusetts corporation (the “Company”), on                    , 201   (the “Grant Date”) to                       , an employee of the Company (the “Participant”), of an option to purchase, in whole or in part, on the terms provided herein and in the Company’s Amended and Restated 2005 Stock Incentive Plan (the “Plan”), a total of       shares (the “Shares”) of Common Stock of the Company (“Common Stock”) at $                per Share. Unless earlier terminated, this option shall expire on (the “Final Exercise Date”).

It is intended that the option evidenced by this agreement shall be an incentive stock option as defined in Section 422 of the Internal Revenue Code of 1986, as amended, and any regulations promulgated thereunder (the “Code”). Except as otherwise indicated by the context, the term “Participant”, as used in this option, shall be deemed to include any person who acquires the right to exercise this option validly under its terms.

The option evidenced by this agreement is intended to qualify as an option substitution under Treas. Regs. §1.409A-1(b)(5)(v)(D) and Treas. Regs. §1.424-1(a), and will be construed accordingly. Without limiting the foregoing, this option will (i) expire not later than the latest date on which the corresponding Ironwood Pharmaceuticals, Inc. option (the “Ironwood Option”) would have expired and (ii) be governed in all respects by the terms of the corresponding Ironwood Option, except for (A) the number and type of shares of Common Stock subject to this option, (B) the exercise price of this option, (C) the post-termination exercise provisions set forth herein, (D) the provisions of Section 8 of the Plan, (E) the provisions of the Plan applicable to governance, amendment, termination, administration, interpretation and similar matters, and (F) all other provisions of the Plan that as applied to this option would not be treated as inconsistent with satisfaction of the requirements of Treas. Regs. §1.409A-1(b)(5)(v)(D) and Treas. Regs. §1.424-1(a).

2.                                      Vesting Schedule.

This option will become exercisable (“vest”) as to            . The shares subject to the portion of this option that are not yet exercisable are referred to herein as “Unvested Shares” and the shares subject to the portion of this option that have become exercisable are referred to herein as “Vested Shares”.

The right of exercise shall be cumulative so that to the extent the option is not exercised in any period to the maximum extent permissible it shall continue to be exercisable, in whole or in part, with respect to all shares for which it is vested until the earlier of the Final Exercise Date or the termination of this option under Section 3 hereof or the Plan.

3.                                      Exercise of Option.

(a)                                 Form of Exercise. Each election to exercise this option shall be in writing in a form acceptable to the Administrator and received by the Company at its principal office, accompanied by this agreement, and payment in full in the manner provided in the Plan. The Participant may purchase less than the number of shares covered hereby, provided that no partial exercise of this option may be for any fractional share or for fewer than ten whole shares.

(b)                                 Continuous Relationship with the Company Required. Except as otherwise provided in this Section 3, this option may not be exercised unless the Participant, at the time he or she exercises this option, is, and has been at all times since the Grant Date, an employee or officer of, or consultant or advisor to, the Company or any parent or subsidiary of the Company as defined in Section 424(e) or (f) of the Code (an “Eligible Participant”).

(c)                                  Termination of Relationship with the Company. If the Participant ceases to be an Eligible Participant for any reason, then, except as provided in paragraphs (d) and (e) below, the right to exercise this option shall terminate three months after such cessation (but in no event after the Final Exercise Date), provided that this option shall be exercisable only to the extent that the Participant was entitled to exercise this option on the date of such cessation. Notwithstanding the foregoing, if the Participant, prior to the Final Exercise Date, violates the non-competition or confidentiality provisions of any employment contract, confidentiality and nondisclosure agreement or other agreement between the Participant and the Company, the right to exercise this option shall terminate immediately upon written notice to the Participant from the Company describing such violation.

(d)                                 Exercise Period Upon Death or Disability. If the Participant dies or becomes disabled (within the meaning of Section 22(e)(3) of the Code) prior to the Final Exercise Date while he or she is an Eligible Participant and the Company has not terminated such relationship for “cause” as specified in paragraph (e) below, this option shall be exercisable, within the period of one year following the date of death or disability of the Participant, by the Participant (or in the case of death by an authorized transferee), provided that this option shall be exercisable only to the extent that this option was exercisable by the Participant on the date of his or her death or disability, and further provided that this option shall not be exercisable after the Final Exercise Date.

(e)                                  Discharge for Cause. If the Participant, prior to the Final Exercise Date, is discharged by the Company for “cause” (as defined below), the right to exercise this option shall terminate immediately upon the effective date of such discharge. “Cause” shall mean willful misconduct by the Participant or willful failure by the Participant to perform his or her responsibilities to the Company (including, without limitation, breach by the Participant of any provision of any employment, consulting, advisory, nondisclosure, non-competition or other similar agreement between the Participant and the Company), as determined by the Company, which determination shall be conclusive. The Participant shall be considered to have been discharged for “Cause” if the Company determines, within 30 days after the Participant’s resignation, that discharge for cause was warranted.

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4.                                      Withholding.

No Shares will be issued pursuant to the exercise of this option unless and until the Participant pays to the Company, or makes provision satisfactory to the Company for payment of, any federal, state or local withholding taxes required by law to be withheld in respect of this option.

5.                                      Nontransferability of Option.

This option may not be sold, assigned, transferred, pledged or otherwise encumbered by the Participant, either voluntarily or by operation of law, except by will or the laws of descent and distribution, and, during the lifetime of the Participant, this option shall be exercisable only by the Participant.

6.                                      Disqualifying Disposition.

If the Participant disposes of Shares acquired upon exercise of this option within two years from            or one year after such Shares were acquired pursuant to exercise of this option, the Participant shall notify the Company in writing of such disposition.

7.                                      Provisions of the Plan.

This option is subject to the provisions of the Plan, a copy of which is furnished to the Participant with this option.

8.                                      Participant’s Acknowledgements.

By acceptance of this option, the Participant agrees to the terms and conditions hereof and acknowledges receipt of a copy of the Plan.

IN WITNESS WHEREOF, the Company has caused this option to be executed under its corporate seal by its duly authorized officer. This option shall take effect as a sealed instrument.

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ATTACHMENT II

CYCLERION THERAPEUTICS, INC.

Nonstatutory Stock Option Agreement
Granted under Amended and Restated 2005 Stock Incentive Plan

1.                                      Grant of Option.

This agreement evidences the grant by Cyclerion Therapeutics, Inc., a Massachusetts corporation (the “Company”), on      , 201  (the “Grant Date”) to              , an employee of the Company (the “Participant”), of an option to purchase, in whole or in part, on the terms provided herein and in the Company’s Amended and Restated 2005 Stock Incentive Plan (the “Plan”), a total of       shares (the “Shares”) of Common Stock of the Company (“Common Stock”) at $            per Share. Unless earlier terminated, this option shall expire on             (the “Final Exercise Date”).

It is intended that the option evidenced by this agreement shall not be an incentive stock option as defined in Section 422 of the Internal Revenue Code of 1986, as amended, and any regulations promulgated thereunder (the “Code”). Except as otherwise indicated by the context, the term “Participant”, as used in this option, shall be deemed to include any person who acquires the right to exercise this option validly under its terms.

The option evidenced by this agreement is intended to qualify as an option substitution under Treas. Regs. §1.409A-1(b)(5)(v)(D) and will be construed accordingly. Without limiting the foregoing, this option will (i) expire not later than the latest date on which the corresponding Ironwood Pharmaceuticals, Inc. option (the “Ironwood Option”) would have expired and (ii) be governed in all respects by the terms of the corresponding Ironwood Option, except for (A) the number and type of shares of Common Stock subject to this option, (B) the exercise price of this option, (C) the post-termination exercise provisions set forth herein, (D) the provisions of Section 8 of the Plan, (E) the provisions of the Plan applicable to governance, amendment, termination, administration, interpretation and similar matters, and (F) all other provisions of the Plan that as applied to this option would not be treated as inconsistent with satisfaction of the requirements of Treas. Regs. §1.409A-1(b)(5)(v)(D).

2.                                      Vesting Schedule.

This option will become exercisable (“vest”) as to            . The shares subject to the portion of this option that are not yet exercisable are referred to herein as “Unvested Shares”, and the shares subject to the portion of this option that have become exercisable are referred to herein as “Vested Shares”.

The right of exercise shall be cumulative so that to the extent the option is not exercised in any period to the maximum extent permissible it shall continue to be exercisable, in whole or in part, with respect to all shares for which it is vested until the earlier of the Final Exercise Date or the termination of this option under Section 3 hereof or the Plan.

3.                                      Exercise of Option.

(a)                                 Form of Exercise. Each election to exercise this option shall be in writing in a form acceptable to the Administrator and received by the Company at its principal office, accompanied by this agreement, and payment in full in the manner provided in the Plan. The Participant may purchase less than the number of shares covered hereby, provided that no partial exercise of this option may be for any fractional share or for fewer than ten whole shares.

(b)                                 Continuous Relationship with the Company Required. Except as otherwise provided in this Section 3, this option may not be exercised unless the Participant, at the time he or she exercises this option, is, and has been at all times since the Grant Date, an employee or officer of, or consultant or advisor to, the Company or any parent or subsidiary of the Company as defined in Section 424(e) or (f) of the Code (an “Eligible Participant”).

(c)                                  Termination of Relationship with the Company. If the Participant ceases to be an Eligible Participant for any reason, then, except as provided in paragraphs (d) and (e) below, the right to exercise this option shall terminate three months after such cessation (but in no event after the Final Exercise Date), provided that this option shall be exercisable only to the extent that the Participant was entitled to exercise this option on the date of such cessation. Notwithstanding the foregoing, if the Participant, prior to the Final Exercise Date, violates the non-competition or confidentiality provisions of any employment contract, confidentiality and nondisclosure agreement or other agreement between the Participant and the Company, the right to exercise this option shall terminate immediately upon written notice to the Participant from the Company describing such violation.

(d)                                 Exercise Period Upon Death or Disability. If the Participant dies or becomes disabled (within the meaning of Section 22(e)(3) of the Code) prior to the Final Exercise Date while he or she is an Eligible Participant and the Company has not terminated such relationship for “cause” as specified in paragraph (e) below, this option shall be exercisable, within the period of one year following the date of death or disability of the Participant, by the Participant (or in the case of death by an authorized transferee), provided that this option shall be exercisable only to the extent that this option was exercisable by the Participant on the date of his or her death or disability, and further provided that this option shall not be exercisable after the Final Exercise Date.

(e)                                  Discharge for Cause. If the Participant, prior to the Final Exercise Date, is discharged by the Company for “cause” (as defined below), the right to exercise this option shall terminate immediately upon the effective date of such discharge. “Cause” shall mean willful misconduct by the Participant or willful failure by the Participant to perform his or her responsibilities to the Company (including, without limitation, breach by the Participant of any provision of any employment, consulting, advisory, nondisclosure, non-competition or other similar agreement between the Participant and the Company), as determined by the Company, which determination shall be conclusive. The Participant shall be considered to have been discharged for “Cause” if the Company determines, within 30 days after the Participant’s resignation, that discharge for cause was warranted.

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4.                                      Withholding.

No Shares will be issued pursuant to the exercise of this option unless and until the Participant pays to the Company, or makes provision satisfactory to the Company for payment of, any federal, state or local withholding taxes required by law to be withheld in respect of this option.

5.                                      Nontransferability of Option.

This option may not be sold, assigned, transferred, pledged or otherwise encumbered by the Participant, either voluntarily or by operation of law, except by will or the laws of descent and distribution, and, during the lifetime of the Participant, this option shall be exercisable only by the Participant.

6.                                      Provisions of the Plan.

This option is subject to the provisions of the Plan, a copy of which is furnished to the Participant with this option.

7.                                      Participant’s Acknowledgements.

By acceptance of this option, the Participant agrees to the terms and conditions hereof and acknowledges receipt of a copy of the Plan.

IN WITNESS WHEREOF, the Company has caused this option to be executed under its corporate seal by its duly authorized officer. This option shall take effect as a sealed instrument.

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ATTACHMENT III

CYCLERION THERAPEUTICS, INC.

Nonstatutory Stock Option Agreement
Granted under Amended and Restated 2005 Stock Incentive Plan

1.                                      Grant of Option.

This agreement evidences the grant by Cyclerion Therapeutics, Inc., a Massachusetts corporation (the “Company”), on             , 201   (the “Grant Date”) to             , a consultant of the Company (the “Participant”), of an option to purchase, in whole or in part, on the terms provided herein and in the Company’s Amended and Restated 2005 Stock Incentive Plan (the “Plan”), a total of        shares (the “Shares”) of Common Stock of the Company (“Common Stock”) at $         per Share. Unless earlier terminated, this option shall expire on (the “Final Exercise Date”).

It is intended that the option evidenced by this agreement shall not be an incentive stock option as defined in Section 422 of the Internal Revenue Code of 1986, as amended, and any regulations promulgated thereunder (the “Code”). Except as otherwise indicated by the context, the term “Participant”, as used in this option, shall be deemed to include any person who acquires the right to exercise this option validly under its terms.

The option evidenced by this agreement is intended to qualify as an option substitution under Treas. Regs. §1.409A-1(b)(5)(v)(D) and will be construed accordingly. Without limiting the foregoing, this option will (i) expire not later than the latest date on which the corresponding Ironwood Pharmaceuticals, Inc. option (the “Ironwood Option”) would have expired and (ii) be governed in all respects by the terms of the corresponding Ironwood Option, except for (A) the number and type of shares of Common Stock subject to this option, (B) the exercise price of this option, (C) the post-termination exercise provisions set forth herein, (D) the provisions of Section 8 of the Plan, (E) the provisions of the Plan applicable to governance, amendment, termination, administration, interpretation and similar matters, and (F) all other provisions of the Plan that as applied to this option would not be treated as inconsistent with satisfaction of the requirements of Treas. Regs. §1.409A-1(b)(5)(v)(D).

2.                                      Vesting Schedule.

This option will become exercisable (“vest”) as to            . The shares subject to the portion of this option that are not yet exercisable are referred to herein as “Unvested Shares” and the shares subject to the portion of this option that have become exercisable are referred to herein as “Vested Shares”.

The right of exercise shall be cumulative so that to the extent the option is not exercised in any period to the maximum extent permissible it shall continue to be exercisable, in whole or in part, with respect to all shares for which it is vested until the earlier of the Final Exercise Date or the termination of this option under Section 3 hereof or the Plan.

3.                                      Exercise of Option.

(a)                                 Form of Exercise. Each election to exercise this option shall be in writing in a form acceptable to the Administrator and received by the Company at its principal office, accompanied by this agreement, and payment in full in the manner provided in the Plan. The Participant may purchase less than the number of shares covered hereby, provided that no partial exercise of this option may be for any fractional share or for fewer than ten whole shares.

(b)                                 Continuous Relationship with the Company Required. Except as otherwise provided in this Section 3, this option may not be exercised unless the Participant, at the time he or she exercises this option, is, and has been at all times since the Grant Date, an employee or officer of, or consultant or advisor to, the Company or any parent or subsidiary of the Company as defined in Section 424(e) or (f) of the Code (an “Eligible Participant”).

(c)                                  Termination of Relationship with the Company. If the Participant ceases to be an Eligible Participant for any reason, then, except as provided in paragraphs (d) and (e) below, the right to exercise this option shall terminate three months after such cessation (but in no event after the Final Exercise Date), provided that this option shall be exercisable only to the extent that the Participant was entitled to exercise this option on the date of such cessation. Notwithstanding the foregoing, if the Participant, prior to the Final Exercise Date, violates the non-competition or confidentiality provisions of any employment contract, confidentiality and nondisclosure agreement or other agreement between the Participant and the Company, the right to exercise this option shall terminate immediately upon written notice to the Participant from the Company describing such violation.

(d)                                 Exercise Period Upon Death or Disability. If the Participant dies or becomes disabled (within the meaning of Section 22(e)(3) of the Code) prior to the Final Exercise Date while he or she is an Eligible Participant and the Company has not terminated such relationship for “cause” as specified in paragraph (e) below, this option shall be exercisable, within the period of one year following the date of death or disability of the Participant, by the Participant (or in the case of death by an authorized transferee), provided that this option shall be exercisable only to the extent that this option was exercisable by the Participant on the date of his or her death or disability, and further provided that this option shall not be exercisable after the Final Exercise Date.

(e)                                  Discharge for Cause. If the Participant, prior to the Final Exercise Date, is discharged by the Company for “cause” (as defined below), the right to exercise this option shall terminate immediately upon the effective date of such discharge. “Cause” shall mean willful misconduct by the Participant or willful failure by the Participant to perform his or her responsibilities to the Company (including, without limitation, breach by the Participant of any provision of any employment, consulting, advisory, nondisclosure, non-competition or other similar agreement between the Participant and the Company), as determined by the Company, which determination shall be conclusive. The Participant shall be considered to have been discharged for “Cause” if the Company determines, within 30 days after the Participant’s resignation, that discharge for cause was warranted.

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4.                                      Withholding.

No Shares will be issued pursuant to the exercise of this option unless and until the Participant pays to the Company, or makes provision satisfactory to the Company for payment of, any federal, state or local withholding taxes required by law to be withheld in respect of this option.

5.                                      Nontransferability of Option.

This option may not be sold, assigned, transferred, pledged or otherwise encumbered by the Participant, either voluntarily or by operation of law, except by will or the laws of descent and distribution, and, during the lifetime of the Participant, this option shall be exercisable only by the Participant.

6.                                      Provisions of the Plan.

This option is subject to the provisions of the Plan, a copy of which is furnished to the Participant with this option.

7.                                      Participant’s Acknowledgements.

By acceptance of this option, the Participant agrees to the terms and conditions hereof and acknowledges receipt of a copy of the Plan.

IN WITNESS WHEREOF, the Company has caused this option to be executed under its corporate seal by its duly authorized officer. This option shall take effect as a sealed instrument.

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Exhibit 5.1

March 29, 2019

Cyclerion Therapeutics, Inc.

301 Binney Street

Cambridge, Massachusetts 02142

Ladies and Gentlemen:

This opinion letter is furnished to you in connection with the registration statement on Form S-8 (the “Registration Statement”), filed by Cyclerion Therapeutics, Inc., a Massachusetts corporation (the “Company”), on the date hereof, with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Securities Act”), for the registration of 11,350,000 shares of Common Stock, with no par value, of the Company (the “Shares”).

The Shares are issuable under the Cyclerion Therapeutics, Inc. 2019 Equity Incentive Plan, the Cyclerion Therapeutics, Inc. 2019 Employee Stock Purchase Plan, the Cyclerion Therapeutics, Inc. Amended and Restated 2010 Employee, Director and Consultant Equity Incentive Plan and the Cyclerion Therapeutics, Inc. Amended and Restated 2005 Stock Incentive Plan (each, a “Plan,” and together, the “Plans”).

We are familiar with the actions taken by the Company in connection with the adoption of the Plans.  We have examined such certificates, documents and records and have made such investigation of fact and such examination of law as we have deemed appropriate in order to enable us to render the opinions set forth herein.  In conducting such investigation, we have relied, without independent verification, upon certificates of officers of the Company, public officials and other appropriate persons.

The opinions expressed below are limited to the laws of the Commonwealth of Massachusetts.

Based upon and subject to the foregoing, we are of the opinion that the Shares have been duly authorized and, when the Shares have been issued and sold in accordance with the terms of the applicable Plan, the Shares will be validly issued, fully paid and nonassessable.

We hereby consent to the filing of this opinion letter as an exhibit to the Registration Statement.  In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations thereunder.

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the Registration Statement (Form S-8) pertaining to the 2019 Employee Stock Purchase Plan and 2019 Equity Incentive Plan of Cyclerion Therapeutics, Inc. of our reports dated March 4, 2019, with respect to the combined financial statements of Cyclerion Therapeutics, Inc.  included in its Annual Report (Form 10) for the year ended December 31, 2018, filed with the Securities and Exchange Commission.

/s/ Ernst & Young LLP

Boston, Massachusetts

March 29, 2019