Exhibit 3.2

AMENDED AND RESTATED BYLAWS

SIGILON THERAPEUTICS, INC.

(a Delaware corporation)

ARTICLE I

STOCKHOLDERS

Section 1. Annual Meetings. The annual meeting of the stockholders of Sigilon Therapeutics, Inc. (the “Corporation”) for the election of directors and for the transaction of such other business as may properly come before the meeting shall be held each year at such date and time, within or without the State of Delaware, as the board of directors of the Corporation (the “Board of Directors”) shall determine.

Section 2. Special Meetings. Special meetings of stockholders for the transaction of such business as may properly come before the meeting may be called by order of the Board of Directors or by stockholders holding together at least a majority of all the shares of the Corporation entitled to vote at the meeting, and shall be held at such date and time, within or without the State of Delaware, as may be specified by such order. Whenever the directors shall fail to fix such place, the meeting shall be held at the principal executive office of the Corporation.

Section 3. Notice of Meetings. Written notice of all meetings of the stockholders, stating the place, date and hour of the meeting, the means of remote communications, if any, by which stockholders and proxy holders may be deemed to be present in person and vote at such meeting, and the place within the city or other municipality or community at which the list of stockholders may be examined, shall be mailed or delivered to each stockholder entitled to vote at such meeting not less than 10 nor more than 60 days prior to the meeting. Notice of any special meeting shall state in general terms the purpose or purposes for which the meeting is to be held.

Section 4. Stockholder Lists. The officer who has charge of the stock ledger of the Corporation shall prepare and make, at least 10 days before every meeting of stockholders, a complete list of the stockholders entitled to vote at the meeting, arranged in alphabetical order, and showing the address of each stockholder and the number and class of shares registered in the name of each stockholder. Such list shall be open to the examination of any stockholder, for any purpose germane to the meeting, either at a place within the city where the meeting is to be held, which place shall be specified in the notice of the meeting, or, if not so specified, at the place where the meeting is to be held. The list shall also be produced and kept at the time and place of the meeting during the whole time thereof, and may be inspected by any stockholder who is present.

The stock ledger shall be the only evidence as to who are the stockholders entitled to examine the stock ledger, the list required by this section or the books of the Corporation, or to vote in person or by proxy at any meeting of stockholders.

Section 5. Quorum. Except as otherwise provided by law or the Corporation’s certificate of incorporation (the “Certificate of Incorporation”), a quorum for the transaction of business at any meeting of stockholders shall consist of the holders of record of a majority of the issued and outstanding shares of the capital stock of the Corporation entitled to vote at the meeting,

present in person or represented by proxy. At all meetings of the stockholders at which a quorum is present, all matters, except as otherwise provided by law or the Certificate of Incorporation, shall be decided by the vote of the holders of a majority of the shares entitled to vote thereat present in person or by proxy. If there be no such quorum, the holders of a majority of such shares so present or represented may adjourn the meeting from time to time, without further notice, until a quorum shall have been obtained. When a quorum is once present it is not broken by the subsequent withdrawal of any stockholder.

Section 6. Organization. Meetings of stockholders shall be presided over by the Chairman, if any, or if none or in the Chairman’s absence the Vice Chairman, if any, or if none or in the Vice Chairman’s absence, the President, if any, or if none or in the President’s absence a Vice President, or, if none of the foregoing is present, by a chairman to be chosen by the stockholders entitled to vote who are present in person or by proxy at the meeting. The Secretary of the Corporation, or in the Secretary’s absence, the presiding officer of the meeting shall appoint any person present to act as secretary of the meeting.

Section 7. Voting; Proxies; Required Vote.

(a) At each meeting of stockholders, every stockholder entitled to vote at such meeting shall be entitled to vote in person or by proxy appointed by instrument in writing, subscribed by such stockholder or by such stockholder’s duly authorized attorney-in-fact (but no such proxy shall be voted or acted upon after three years from its date, unless the proxy provides for a longer period), and, unless the Certificate of Incorporation provides otherwise, shall have one vote for each share of stock entitled to vote registered in the name of such stockholder on the books of the Corporation on the applicable record date fixed pursuant to these Bylaws. At all elections of directors the voting may be, but need not be, by ballot and a plurality of the votes cast there shall elect such directors. Except as otherwise required by law or the Certificate of Incorporation, any other action shall be authorized by a majority of the votes cast.

(b) Any action required or permitted to be taken at any meeting of stockholders may, except as otherwise required by law or the Certificate of Incorporation, be taken without a meeting, without prior notice and without a vote, if a consent in writing, setting forth the action so taken, shall be signed by the holders of record of the issued and outstanding capital stock of the Corporation having the number of votes that would be necessary to authorize or take such action at a meeting at which all shares entitled to vote thereon were present and voted, and the writing or writings are filed with the permanent records of the Corporation. Prompt notice of the taking of corporate action without a meeting by less than unanimous written consent shall be given to those stockholders who have not consented in writing.

(c) Where a separate vote is to be taken by a class or classes, the presence in person or by proxy of a majority of the holders of record of such class or classes shall constitute a quorum and the affirmative vote of the majority of shares of such class or classes present in person or represented by proxy at the meeting shall be the act of such class, unless otherwise provided in the Certificate of Incorporation.

Section 8. Inspectors. The Board of Directors, in advance of any meeting, may, but need not, appoint one or more inspectors of election to act at the meeting or any adjournment thereof. If an inspector or inspectors are not so appointed, the person presiding at the meeting may, but need not, appoint one or more inspectors. In case any person who may be appointed as an inspector fails to appear or act, the vacancy may be filled by appointment made by the directors in advance of the meeting or at the meeting by the person presiding thereat. Each inspector, if any, before entering upon the discharge of his or her duties, shall take and sign an oath faithfully to execute the duties of inspector at such meeting with strict impartiality and according to the best of his or her ability. The inspectors, if any, shall determine the number of shares of stock outstanding and the voting power of each, the shares of stock represented at the meeting, the existence of a quorum, and the validity and effect of proxies, and shall receive votes, ballots or consents, hear and determine all challenges and questions arising in connection with the right to vote, count and tabulate all votes, ballots or consents, determine the result, and do such acts as are proper to conduct the election or vote with fairness to all stockholders. On request of the person presiding at the meeting, the inspector or inspectors, if any, shall make a report in writing of any challenge, question or matter determined by such inspector or inspectors and execute a certificate of any fact found by such inspector or inspectors.

ARTICLE II

BOARD OF DIRECTORS

Section 1. General Powers. The business, property and affairs of the Corporation shall be managed by, or under the direction of, the Board of Directors.

Section 2. Qualification; Number; Term; Compensation.

(a) Each director shall be at least 18 years of age. A director need not be a stockholder, a citizen of the United States or a resident of the State of Delaware. The number of directors constituting the entire Board of Directors shall be fixed initially by the incorporator and thereafter by the Board of Directors and shall be at least one, or such larger number as may be fixed initially by the incorporator and thereafter from time to time by the Board of Directors, one of whom may be selected by the Board of Directors to be its Chairman. The use of the phrase “entire Board of Directors” herein refers to the total number of directors which the Corporation would have if there were no vacancies.

(b) Directors who are elected at an annual meeting of stockholders, and directors who are elected in the interim to fill vacancies and newly created directorships, shall hold office until the next annual meeting of stockholders and until their successors are elected and qualified or until their earlier resignation or removal.

(c) Unless otherwise restricted by the Certificate of Incorporation or these Bylaws, the Board of Directors shall have the authority to fix the compensation of directors. The directors may be paid their expenses, if any, of attendance at each meeting of the Board of Directors and may be paid a fixed sum for attendance at each meeting of the Board of Directors or a stated salary as director. No such payment shall preclude any director from serving the Corporation in any other capacity and receiving compensation therefor. Members of special or standing committees may be allowed like compensation for attending committee meetings.

Section 3. Quorum and Manner of Voting. Except as otherwise provided by law, a majority of the entire Board of Directors shall constitute a quorum. A majority of the directors present, whether or not a quorum is present, may adjourn a meeting from time to time to another time and place without notice. The vote of the majority of the directors present at a meeting at which a quorum is present shall be the act of the Board of Directors.

Section 4. Places of Meetings. Meetings of the Board of Directors may be held at any place within or without the State of Delaware, as may from time to time be fixed by resolution of the Board of Directors, or as may be specified in the notice of meeting.

Section 5. Annual Meeting. Following the annual meeting of stockholders, the newly elected Board of Directors shall meet for the purpose of the election of officers and the transaction of such other business as may properly come before the meeting. Such meeting may be held without notice immediately after the annual meeting of stockholders at the same place at which such stockholders’ meeting is held.

Section 6. Regular Meetings. Regular meetings of the Board of Directors shall be held at such times and places as the Board of Directors shall from time to time determine by resolution. Notice need not be given of regular meetings of the Board of Directors held at times and places fixed by resolution of the Board of Directors.

Section 7. Special Meetings. Special meetings of the Board of Directors shall be held whenever called by the Chairman of the Board of Directors, the President or by a majority of directors then in office. Notice of the place, date and time and the purpose or purposes of each special meeting of the Board of Directors shall be given to each director by mailing the same at least two days before the meeting, or by telephoning or emailing the same or by delivering the same personally not later than the day before the day of the meeting.

Section 8. Meetings by Means of Conference Telephone. Unless otherwise provided by the Certificate of Incorporation or these Bylaws, members of the Board of Directors, or any committee designated by the Board of Directors, may participate in a meeting of the Board of Directors or such committee by means of a conference telephone or similar communication equipment by means of which all persons participating in the meeting can hear each other, and such participation in a meeting pursuant to this Section 8 shall constitute presence at such meeting.

Section 9. Organization. The Chairman of the Board of Directors, if there be one, or if none or in the Chairman’s absence or inability to act the Vice Chairman, if any, or if none or in the Vice Chairman’s absence or inability to act the President, or in the President’s absence or inability to act any Vice President who is a member of the Board of Directors, or in such Vice President’s absence or inability to act, a chairman chosen by the directors, shall preside at all meetings of the Board of Directors and shall have such other powers and duties as may from time to time be assigned by the Board of Directors. The Secretary of the Corporation shall act as secretary at all meetings of the Board of Directors when present, and, in the Secretary’s absence, the presiding officer may appoint any person to act as secretary.

Section 10. Resignation; Removal. Any director may resign at any time upon written notice to the Corporation and such resignation shall take effect upon receipt thereof by the President or Secretary, unless otherwise specified in the resignation. Any or all of the directors may be removed, with or without cause, by the holders of a majority of the shares of stock outstanding and entitled to vote for the election of directors.

Section 11. Vacancies. Unless otherwise provided in these Bylaws, vacancies on the Board of Directors, whether caused by resignation, death, disqualification, removal, an increase in the authorized number of directors or otherwise, may be filled by the affirmative vote of a majority of the remaining directors, although less than a quorum, or by a sole remaining director, or at a special meeting of the stockholders, by the holders of shares entitled to vote for the election of directors.

Section 12. Action by Written 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 thereto in writing, and the writing or writings are filed with the minutes of proceedings of the Board of Directors.

ARTICLE III

COMMITTEES

Section 1. Appointment. From time to time the Board of Directors by a resolution adopted by a majority of the entire Board of Directors may appoint any committee or committees for any purpose or purposes, to the extent lawful, which shall have powers as shall be determined and specified by the Board of Directors in the resolution of appointment.

Section 2. Procedures, Quorum and Manner of Acting. Each committee shall fix its own rules of procedure, and shall meet where and as provided by such rules or by resolution of the Board of Directors. Except as otherwise provided by law, the presence of a majority of the then appointed members of a committee shall constitute a quorum for the transaction of business by that committee, and in every case where a quorum is present the affirmative vote of a majority of the members of the committee present shall be the act of the committee. Each committee shall keep minutes of its proceedings, and actions taken by a committee shall be reported to the Board of Directors.

Section 3. Action by Written Consent. Any action required or permitted to be taken at any meeting of any committee of the Board of Directors may be taken without a meeting if all the members of the committee consent thereto in writing, and the writing or writings are filed with the minutes of proceedings of the committee.

Section 4. Term; Termination. In the event any person shall cease to be a director of the Corporation, such person shall simultaneously therewith cease to be a member of any committee appointed by the Board of Directors.

ARTICLE IV

OFFICERS

Section 1. Election and Qualifications. The Board of Directors shall elect the officers of the Corporation, which shall include a President and a Secretary, and may include, by election or appointment, one or more Vice Presidents (any one or more of whom may be given an additional designation of rank or function), a Treasurer and such Assistant Secretaries, such Assistant Treasurers and such other officers as the Board of Directors may from time to time deem proper. Each officer shall have such powers and duties as may be prescribed by these Bylaws and as may be assigned by the Board of Directors or the President. Any two or more offices may be held by the same person. The Chairman of the Board of Directors, if one is appointed, shall, if present, preside at all meetings of the stockholders.

Section 2. Term of Office and Remuneration. All officers shall hold office until their successors are elected and qualified. Any vacancy in any office arising from any cause may be filled for the unexpired portion of the term by the Board of Directors. The remuneration of all officers of the Corporation may be fixed by the Board of Directors or in such manner as the Board of Directors shall provide.

Section 3. Resignation; Removal. Any officer may resign at any time upon written notice to the Corporation and such resignation shall take effect upon receipt thereof by the President or Secretary, unless otherwise specified in the resignation. Any officer shall be subject to removal, with or without cause, at any time by vote of a majority of the entire Board of Directors.

Section 4. President. The President shall, subject to control of the Board of Directors, have direction and control of the business and officers of the Corporation, shall have the general powers and duties of management usually vested in the president of a corporation, and shall have such other powers and duties as may from time to time be assigned by the Board of Directors. The President may appoint and remove assistant officers and other agents and employees; and may execute and deliver in the name of the Corporation powers of attorney, contracts, bonds and other obligations and instruments.

Section 5. Vice President. A Vice President may execute and deliver in the name of the Corporation contracts and other obligations and instruments pertaining to the regular course of the duties of said office, and shall have such other authority as from time to time may be assigned by the Board of Directors.

Section 6. Treasurer. The Treasurer (if any) shall in general have all duties incident to the position of Treasurer and such other duties as may be assigned by the Board of Directors.

Section 7. Secretary. The Secretary shall in general have all the duties incident to the office of Secretary and such other duties as may be assigned by the Board of Directors.

Section 8. Other Officers. Such other officers as the Board of Directors may choose shall perform such duties and have such powers as from time to time may be assigned to them by the Board of Directors. The Board of Directors may delegate to any other officer of the Corporation the power to choose such other officers and to prescribe their respective duties and powers.

ARTICLE V

BOOKS AND RECORDS

Section 1. Location. The books and records of the Corporation may be kept at such place or places within or outside the State of Delaware as the Board of Directors or the respective officers in charge thereof may from time to time determine. The record books containing the names and addresses of all stockholders, the number and class of shares of stock held by each and the dates when they respectively became the owners of record thereof shall be kept by the Secretary as prescribed in these Bylaws and by such officer or agent as shall be designated by the Board of Directors.

Section 2. Addresses of Stockholders. Notices of meetings and all other corporate notices may be delivered personally or mailed to each stockholder at the stockholder’s address as it appears on the records of the Corporation.

Section 3. Fixing Date for Determination of Stockholders of Record.

(a) In order that the Corporation may determine the stockholders entitled to notice of or to vote at any meeting of stockholders or any adjournment thereof, the Board of Directors may fix a record date, which record date shall not precede the date upon which the resolution fixing the record date is adopted by the Board of Directors and which record date shall not be more than 60 nor less than 10 days before the date of such meeting. If no record date is fixed by the Board of Directors, the record date for determining stockholders entitled to notice of or to vote at a meeting of stockholders shall be at the close of business on the day next preceding the day on which notice is given, or, if notice is waived, at the close of business on the day next preceding the day on which the meeting is held. A determination of stockholders of record entitled to notice of or to vote at a meeting of stockholders shall apply to any adjournment of the meeting; provided, however, that the Board of Directors may fix a new record date for the adjourned meeting.

(b) In order that the Corporation may determine the stockholders entitled to consent to corporate action in writing without a meeting, the Board of Directors may fix a record date, which record date shall not precede the date upon which the resolution fixing the record date is adopted by the Board of Directors and if no record date has been fixed by the Board of Directors, the record date for determining stockholders entitled to consent to corporate action in writing without a meeting, when no prior action by the Board of Directors is required, shall be the first date on which a signed written consent setting forth the action taken or proposed to be taken is delivered to the Corporation by delivery to its registered office in this State, its principal place of business, or an officer or agent of the Corporation having custody of the book in which proceedings of meetings of stockholders are recorded. Delivery made to the Corporation’s registered office shall be by hand or by certified or registered mail, return receipt requested. If no record date has been fixed by the Board of Directors and prior action by the Board of Directors is required by this article, the record date for determining stockholders entitled to consent to corporate action in writing without a meeting shall be at the close of business on the day on which the Board of Directors adopts the resolution taking such prior action.

(c) In order that the Corporation may determine the stockholders entitled to receive payment of any dividend or other distribution or allotment of any rights or the stockholders entitled to exercise any rights in respect of any change, conversion or exchange of stock, or for the purpose of any other lawful action, the Board of Directors may fix a record date, which record date shall not precede the date upon which the resolution fixing the record date is adopted and if no record date is fixed, the record date for determining stockholders for any such purpose shall be at the close of business on the day on which the Board of Directors adopts the resolution relating thereto.

ARTICLE VI

CERTIFICATES REPRESENTING STOCK

Section 1. Certificates; Signatures. Unless, to the extent permitted by applicable law, the Board of Directors has resolved that any series or class of shares of capital stock of the Corporation shall be uncertificated, upon request every holder of shares shall be entitled to have a certificate, signed by or in the name of the Corporation by any two officers of the Corporation, representing the number of shares registered in such holder’s name. Any and all signatures on any such certificate may be facsimiles. In case any officer, transfer agent or registrar who has signed or whose facsimile signature has been placed upon a certificate shall have ceased to be such officer, transfer agent or registrar before such certificate is issued, it may be issued by the Corporation with the same effect as if he were such officer, transfer agent or registrar at the date of issue. The name of the holder of record of the shares represented thereby, with the number of such shares and the date of issue, shall be entered on the books of the Corporation.

Section 2. Transfers of Stock. Upon compliance with provisions restricting the transfer or registration of transfer of shares of stock, if any, shares of capital stock shall be transferable on the books of the Corporation only by the holder of record thereof in person, or by a duly authorized attorney, upon surrender and cancellation of certificates for a like number of shares, properly endorsed, and the payment of all taxes due thereon.

Section 3. Fractional Shares. The Corporation may, but shall not be required to, issue certificates for fractions of a share where necessary to effect authorized transactions, or the Corporation may pay in cash the fair value of fractions of a share as of the time when those entitled to receive such fractions are determined, or it may issue scrip in registered or bearer form over the manual or facsimile signature of an officer of the Corporation or of its agent, exchangeable as therein provided for full shares, but such scrip shall not entitle the holder to any rights of a stockholder except as therein provided.

Section 4. Rules and Regulations. The Board of Directors shall have power and authority to make all such rules and regulations as it may deem expedient concerning the issue, transfer and registration of certificates representing shares of the Corporation.

Section 5. Lost, Stolen or Destroyed Certificates. The Corporation may issue a new certificate of stock in place of any certificate, theretofore issued by it, alleged to have been lost, stolen or destroyed, and the Board of Directors may require the owner of any lost, stolen or destroyed certificate, or his legal representative, to give the Corporation a bond sufficient to indemnify the Corporation against any claim that may be made against it on account of the alleged loss, theft or destruction of any such certificate or the issuance of any such new certificate.

ARTICLE VII

DIVIDENDS

Subject always to the provisions of applicable law and the Certificate of Incorporation, the Board of Directors shall have full power to determine whether any, and, if any, what part of any, funds legally available for the payment of dividends shall be declared as dividends and paid to stockholders; the division of the whole or any part of such funds of the Corporation shall rest wholly within the lawful discretion of the Board of Directors, and it shall not be required at any time, against such discretion, to divide or pay any part of such funds among or to the stockholders as dividends or otherwise; and before payment of any dividend, there may be set aside out of any funds of the Corporation legally available for dividends such sum or sums as the Board of Directors from time to time, in its absolute discretion, deems proper as a reserve or reserves to meet contingencies, or for equalizing dividends, or for repairing or maintaining any property of the Corporation, or for such other purpose as the Board of Directors shall think conducive to the interest of the Corporation, and the Board of Directors may modify or abolish any such reserve in the manner in which it was created.

ARTICLE VIII

RATIFICATION

Any transaction, questioned in any lawsuit on the ground of lack of authority, defective or irregular execution, adverse interest of director, officer or stockholder, non-disclosure, miscomputation, or the application of improper principles or practices of accounting, may be ratified before or after judgment, by the Board of Directors or by the stockholders, and if so ratified shall have the same force and effect as if the questioned transaction had been originally duly authorized. Such ratification shall be binding upon the Corporation and its stockholders and shall constitute a bar to any claim or execution of any judgment in respect of such questioned transaction.

ARTICLE IX

CORPORATE SEAL

The Corporation may have a corporate seal. The corporate seal shall have inscribed thereon the name of the Corporation and the year of its incorporation, and shall be in such form and contain such other words and/or figures as the Board of Directors shall determine. The corporate seal may be used by printing, engraving, lithographing, stamping or otherwise making, placing or affixing, or causing to be printed, engraved, lithographed, stamped or otherwise made, placed or affixed, upon any paper or document, by any process whatsoever, an impression, facsimile or other reproduction of said corporate seal.

ARTICLE X

FISCAL YEAR

The fiscal year of the Corporation shall be fixed, and shall be subject to change, by the Board of Directors. Unless otherwise fixed by the Board of Directors, the fiscal year of the Corporation shall be the calendar year.

ARTICLE XI

WAIVER OF NOTICE

Whenever notice is required to be given by these Bylaws or by the Certificate of Incorporation or by law, a written waiver thereof, signed by the person or persons entitled to such notice, whether before or after the time stated therein, shall be deemed equivalent to notice.

ARTICLE XII

BANK ACCOUNTS, DRAFTS, CONTRACTS, ETC.

Section 1. Bank Accounts and Drafts. In addition to such bank accounts as may be authorized by the Board of Directors, the primary financial officer or any person designated by said primary financial officer or otherwise authorized by the Board of Directors, whether or not an employee of the Corporation, may authorize such bank accounts to be opened or maintained in the name and on behalf of the Corporation as he may deem necessary or appropriate, payments from such bank accounts to be made upon and according to the check of the Corporation in accordance with the written instructions of said primary financial officer, or other person so authorized.

Section 2. Contracts. The Board of Directors may authorize any person or persons, in the name and on behalf of the Corporation, to enter into or execute and deliver any and all deeds, bonds, mortgages, contracts and other obligations or instruments (including powers of attorney), and such authority may be general or confined to specific instances.

Section 3. Proxies; Powers of Attorney; Other Instruments. The Chairman, the President or any other person designated by either of them shall have the power and authority to execute and deliver proxies, powers of attorney and other instruments on behalf of the Corporation in connection with the rights and powers incident to the ownership of stock by the Corporation. The Chairman, the President or any other person authorized by proxy or power of attorney executed and delivered by either of them on behalf of the Corporation may attend and vote at any meeting of stockholders of any company in which the Corporation may hold stock, and may exercise on behalf of the Corporation any and all of the rights and powers incident to the ownership of such stock at any such meeting, or otherwise as specified in the proxy or power of attorney so authorizing any such person. The Board of Directors, from time to time, may confer like powers upon any other person.

Section 4. Financial Reports. The Board of Directors may appoint the primary financial officer or other fiscal officer or any other officer to cause to be prepared and furnished to stockholders entitled thereto any special financial notice and/or financial statement, as the case may be, which may be required by any provision of law.

ARTICLE XIII

INDEMNIFICATION AND INSURANCE

Section 1. Indemnification.

(a) Each person who was or is made a party or is threatened to be made a party to or is involved in (as a witness or otherwise) any action, suit, arbitration, alternate dispute resolution mechanism, investigation, inquiry, administrative hearing or any other proceeding, whether civil, criminal, administrative or investigative in nature (hereinafter a “proceeding”), by reason of the fact that he or she or a person of whom he or she is the legal representative (in the event of death or disability of such person) is or was a director or officer of the Corporation (or any predecessor) or is or was serving at the request of the Corporation (or any predecessor) as a director, officer, employee, fiduciary, representative, partner or agent of another corporation or of a partnership, joint venture, trust, employee benefit plan sponsored or maintained by the

Corporation, or other enterprise (or any predecessor of any of such entities), whether the basis of such proceeding is alleged action or inaction in an official capacity as a director, officer, employee, fiduciary, representative, partner or agent or in any other capacity while serving as a director, officer, employee, fiduciary, representative, partner or agent, shall be indemnified and held harmless by the Corporation to the fullest extent authorized by the General Corporation Law of the State of Delaware (the “DGCL”), as the same exists or may hereafter be amended (but, in the case of any such amendment, only to the extent that such amendment permits the Corporation to provide broader indemnification rights than said law permitted the Corporation to provide prior to such amendment), against all expense, liability and loss (including attorneys’ fees, judgments, fines, ERISA excise taxes or penalties, and amounts paid or to be paid in settlement) reasonably incurred or suffered by such person in connection with such proceeding; provided, however, that except as provided in Section 1(c) of this Article XIII, the Corporation shall indemnify any such person seeking indemnification in connection with a proceeding (or part thereof) initiated by such person only if such proceeding (or part thereof) was authorized by the Board of Directors. The right to indemnification conferred in this Section 1(a) shall be a contract right subject to the terms and conditions of this Article XIII.

(b) To obtain indemnification under this Section 1 a claimant shall submit to the Corporation a written request, including therein or therewith such documentation and information as is reasonably available to the claimant and is reasonably necessary to determine whether and to what extent the claimant is entitled to indemnification; provided, however, that the failure of a claimant to so notify the Corporation shall not relieve the Corporation of any obligation which it may have to the claimant under this Section 1 or otherwise except to the extent that any delay in such notification actually and materially prejudices the Corporation. Upon written request by a claimant for indemnification pursuant to the preceding sentence, a determination, if required by applicable law, with respect to the claimant’s entitlement thereto shall be made as follows: (i) if requested by the claimant, by “Independent Counsel” (as hereinafter defined), or (ii) if no request is made by the claimant for a determination by Independent Counsel, (A) by the Board of Directors by a majority vote of the “Disinterested Directors” (as hereinafter defined), even though less than a quorum, or (B) by a committee of Disinterested Directors designated by majority vote of the Disinterested Directors, even though less than a quorum, or (C) if there are no Disinterested Directors or the Disinterested Directors so direct, by Independent Counsel in a written opinion to the Board of Directors, a copy of which shall be delivered to the claimant, or (D) if a quorum of Disinterested Directors so directs, by the stockholders.

In the event the determination of entitlement to indemnification is to be made by Independent Counsel at the request of the claimant, the Independent Counsel shall be selected by the Board of Directors unless there shall have occurred within two (2) years prior to the date of the commencement of the proceeding for which indemnification is claimed a “Change of Control” (as hereinafter defined), in which case Independent Counsel shall be selected by the claimant unless the claimant shall request that such selection be made by the Board of Directors. In either event, the claimant or the Corporation, as the case may be, shall give written notice to the other advising it of the identity of the Independent Counsel so selected. The party so notified may, within ten (10) days after such written notice of selection shall have been given, deliver to the Corporation or to the claimant, as the case may be, a written objection to such selection; provided, however, that such objection may be asserted only on the ground that the Independent Counsel so selected does not meet the requirements of “Independent Counsel” as defined in Section 6 of this Article XIII,

and the objection shall set forth with particularity the factual basis of such assertion. If such written objection is so made and substantiated, the Independent Counsel so selected may not serve as Independent Counsel unless and until such objection is withdrawn or a court has determined that such objection is without merit. If, within thirty (30) days after submission by the claimant of a written request for indemnification pursuant to this Section 1(b), no Independent Counsel shall have been selected and not objected to, either the Corporation or the claimant may petition the Court of Chancery of the State of Delaware (the “Court”) for resolution of any objection which shall have been made by the Corporation or the claimant to the other’s selection of Independent Counsel or for the appointment as Independent Counsel of a person selected by the Court or by such other person as the Court shall designate, and the person with respect to whom all objections are so resolved or the person so appointed shall act as Independent Counsel hereunder. The Corporation shall pay any and all fees and expenses of Independent Counsel reasonably incurred in connection with acting pursuant to this Section 1(b), and the Corporation shall pay all reasonable fees and expenses incident to the procedures of this Section 1(b), regardless of the manner in which such Independent Counsel was selected or appointed. Upon the due commencement of any judicial proceeding pursuant to Section 1(c) of this Article XIII, Independent Counsel shall be discharged and relieved of any further responsibility in such capacity (subject to the applicable standards of professional conduct then prevailing).

If the person, persons or entity empowered or selected under this Section 1(b) to determine whether the claimant is entitled to indemnification shall not have made a determination within ninety (90) days after receipt by the Corporation of the request therefor, the requisite determination of entitlement to indemnification shall be deemed to have been made and the claimant shall be entitled to such indemnification, absent (i) a misstatement by the claimant of a material fact, or an omission of a material fact necessary to make the claimant’s statement(s) not materially misleading, in connection with the request for indemnification or (ii) a prohibition of such indemnification under applicable law.

If it is determined that the claimant is entitled to indemnification, the Corporation shall pay the claimant within twenty (20) business days after such determination any then known amounts with respect to which it has been so determined that the claimant is entitled to indemnification hereunder and will pay any other amounts thereafter incurred for which the claimant is entitled to indemnification within twenty (20) business days of the Corporation’s receipt of reasonably detailed invoices for such amounts.

(c) In the event that (i) a determination is made pursuant to Section 1(b) of this Article XIII that the claimant is not entitled to indemnification, (ii) advancement of expenses is not timely made pursuant to Section 2 of this Article XIII or (iii) a claim for indemnification under Section 1 of this Article XIII is not paid in full by the Corporation within twenty (20) business days after a determination has been made that the claimant is entitled to indemnification, the claimant may at any time thereafter bring suit against the Corporation to determine his or her entitlement to such indemnification or advancement of expenses and, if successful in whole or in part, the claimant shall be entitled to be paid also the expense of prosecuting such claim. If a Change of Control shall have occurred, in any judicial proceeding commenced pursuant to this Section 1(c), the Corporation shall have the burden of proving that the claimant is not entitled to indemnification. It shall be a defense to any such action (other than an action brought to enforce a claim for expenses incurred in defending any proceeding in advance of its final disposition where

the required undertaking, if any is required, has been tendered to the Corporation) that the claimant has not met the standard of conduct that makes it permissible under the DGCL for the Corporation to indemnify the claimant for the amount claimed, but the burden of proving such defense shall be on the Corporation. Neither the failure of the Corporation (including the Board of Directors, Independent Counsel or stockholders) to have made a determination prior to the commencement of such action that indemnification of the claimant is proper in the circumstances because he or she has met the applicable standard of conduct set forth in the DGCL, nor the fact that the Corporation (including the Board of Directors, Independent Counsel or stockholders) has determined that the claimant has not met such applicable standard of conduct, shall be a defense to the action or create a presumption that the claimant has not met the applicable standard of conduct. The termination of any action, suit or proceeding by judgment, order, settlement, conviction, or upon a plea of nolo contendere or its equivalent, shall not, of itself, create a presumption that the claimant has not met the applicable standard of conduct.

(d) If a determination shall have been made pursuant to this Section 1 that the claimant is entitled to indemnification, the Corporation shall be bound by such determination in any judicial proceeding commenced pursuant to Section 1(c) of this Article XIII, absent (i) a misstatement by the claimant of a material fact, or an omission of a material fact necessary to make the claimant’s statements not materially misleading in connection with a request for indemnification or (ii) a prohibition of such indemnification under applicable law. The Corporation shall be precluded from asserting in any judicial proceeding commenced pursuant to Section 1(c) of this Article XIII that the procedures and presumptions of this Article XIII are not valid, binding and enforceable and shall stipulate in such proceeding that the Corporation is bound by all the provisions of this Article XIII.

(e) With respect to any proceeding for which indemnification is sought hereunder, so long as there shall not have occurred a Change of Control, the Corporation, in its sole discretion, will be entitled to participate in such proceeding at its own expense and, except as provided below, to assume the defense of, and to settle, such proceeding. After notice from the Corporation to the claimant of its election so to assume the defense thereof, the Corporation will not be liable to the claimant under this Article XIII for any legal or other expenses subsequently incurred by the claimant in connection with the defense thereof other than reasonable costs of investigation or as otherwise provided below. The claimant shall have the right to employ its counsel in such proceeding but the fees and expenses of such counsel incurred after notice from the Corporation of its assumption of the defense thereof shall be at the expense of the claimant unless (i) the employment of counsel by the claimant has been authorized by the Corporation, (ii) the claimant shall have reasonably concluded that there may be a conflict of interest between the Corporation and the claimant in the conduct of the defense of such proceeding or (iii) the Corporation shall not in fact have employed counsel to assume the defense of such proceeding, in each of which cases the fees and expenses of counsel shall be at the expense of the Corporation. The Corporation shall not be entitled to assume the defense of any proceeding brought by or on behalf of the Corporation or as to which the claimant shall have made the conclusion provided for in clause (ii) of the immediately preceding sentence. The claimant shall not compromise or settle any claim or proceeding, release any claim, or make any admission of fact, law, liability or damages with respect to any losses for which indemnification is sought hereunder without the prior written consent of the Corporation, which consent shall not be unreasonably withheld (subject to the terms and conditions of this Article XIII, including any determination required by Section 1(b) of this Article XIII or by applicable law). The Corporation shall not be liable for any amount paid by the claimant in settlement of any proceeding or any claim therein, unless the Corporation has consented to such settlement or unreasonably withholds consent to such settlement.

(f) If the claimant is a party to or involved in a proceeding with any other person(s) for whom the Corporation is required to indemnify or advance expenses with respect to such proceeding, the Corporation shall not be required to indemnify against or advance expenses for more than one law firm to represent collectively the claimant and such other person(s) in respect of the same matter unless the representation of the claimant and such other person(s) gives rise to an actual or potential conflict of interest.

Section 2. Advance Payment. The right to indemnification under this Article XIII shall include the right to be paid by the Corporation the expenses incurred in defending any such proceeding in advance of its final disposition, such advances to be paid by the Corporation within twenty (20) business days after the receipt by the Corporation of a statement or statements from the claimant requesting and reasonably evidencing such advance or advances from time to time; provided, however, that if the DGCL requires, the payment of such expenses incurred by a director or officer in his or her capacity as a director or officer (and not in any other capacity in which service was or is rendered by such person while a director or officer, including, without limitation, service to an employee benefit plan) in advance of the final disposition of a proceeding, shall be made only upon delivery to the Corporation of an undertaking by or on behalf of such director or officer to repay all amounts so advanced if it shall ultimately be determined that such director or officer is not entitled to be indemnified under Section 1 of this Article XIII or otherwise.

Section 3. Non-Exclusivity and Survival of Rights; Amendments. The right to indemnification and the payment of expenses incurred in defending a proceeding in advance of its final disposition conferred in this Article XIII shall not be deemed exclusive of any other right which any person may have or hereafter acquire under any statute, provision of the Certificate of Incorporation, these bylaws, agreement, vote of stockholders or Disinterested Directors or otherwise, both as to actions in such person’s official capacity and as to actions in another capacity while holding such office. The indemnification and advancement of expenses provided by, or granted pursuant to, this Article XIII shall, unless otherwise provided when authorized or ratified, continue as to a person who has ceased to be a director, officer, employee or agent of the Corporation and shall inure to the benefit of the heirs, executors and administrators of such a person. Any repeal or modification of the provisions of this Article XIII shall not in any way diminish or adversely affect the rights or protections of any director, officer, employee or agent of the Corporation hereunder in respect of any proceeding (regardless of when such proceeding is first threatened, commenced or completed) arising out of, or related to, any act or omission occurring prior to the time of such repeal or modification.

Section 4. Insurance. The Corporation may purchase and maintain insurance on behalf of any person who is or was a director, officer, employee or agent of the Corporation, or is or was serving at the request of the Corporation as a director, officer, employee, fiduciary, representative, partner or agent of another corporation or of a partnership, joint venture, trust, employee benefit plan sponsored or maintained by the Corporation, or other enterprise (or any predecessor of any of such entities) against any expense, liability or loss asserted against such person and incurred by such person in any such capacity, or arising out of such person’s status as such, whether or not the Corporation would have the power to indemnify such person against such liability under the provisions of the DGCL.

Section 5. Severability. If any word, clause, provision or provisions of this Article XIII shall be held to be invalid, illegal or unenforceable for any reason whatsoever: (i) the validity, legality and enforceability of the remaining provisions of this Article XIII (including, without limitation, each portion of any section or paragraph of this Article XIII containing any such provision held to be invalid, illegal or unenforceable, that is not itself held to be invalid, illegal or unenforceable) shall not in any way be affected or impaired thereby; and (ii) to the fullest extent possible, the provisions of this Article XIII (including, without limitation, each such portion of any section or paragraph of this Article XIII containing any such provision held to be invalid, illegal or unenforceable) shall be construed so as to give effect to the intent manifested by the provision held invalid, illegal or unenforceable.

Section 6. Definitions. For the purpose of this Article XIII:

(a) “Change of Control” shall mean:

(1) the acquisition by any individual, entity or group (within the meaning of Section 13(d)(3) or 14(d)(2) of the Securities Exchange Act of 1934 (such act and the rules and regulations promulgated thereunder as amended from time to time, collectively, the “1934 Act”) (a “Person”)), directly or indirectly, of beneficial ownership (within the meaning of Rule 13d-3 promulgated under the 1934 Act) of 20% or more of either (i) the then outstanding shares of common stock of the Corporation (the “Outstanding Corporation Common Stock”) or (ii) the combined voting power of the then outstanding voting securities of the Corporation entitled to vote generally in the election of directors (the “Outstanding Corporation Voting Securities”); provided, however, that for purposes of this part (1), the following acquisitions shall not constitute a Change of Control: (i) any acquisition directly from the Corporation or any acquisition from other stockholders where (A) such acquisition was approved in advance by the Board of Directors and (B) such acquisition would not constitute a Change of Control under part (2) or part (4) of this definition, (ii) any acquisition by the Corporation, (iii) any acquisition by any employee benefit plan (or related trust) sponsored or maintained by the Corporation or any corporation controlled by the Corporation, or (iv) any acquisition by any corporation pursuant to a transaction that complies with clauses (i), (ii) and (iii) of part (4) of this definition; or

(2) the acquisition by any Person, directly or indirectly, of beneficial ownership (within the meaning of Rule 13d-3 promulgated under the 1934 Act) of 50% or more of either (i) the Outstanding Corporation Common Stock or (ii) the Outstanding Corporation Voting Securities; or

(3) individuals who, as of the date hereof, constitute the Board of Directors (the “Incumbent Board”) cease for any reason to constitute at least a majority of the Board of Directors; provided, however, that any individual becoming a director subsequent to the date hereof whose election, or nomination for election by the stockholders, was approved by a vote of at least a majority of the directors then comprising the Incumbent Board (or such committee thereof that shall then have the authority to nominate persons for election as directors) shall be considered as though such individual were a member of the Incumbent Board, but excluding, for this purpose, any such individual whose initial assumption of office occurs as a result of an actual or threatened election contest with respect to the election or removal of directors or other actual or threatened solicitation of proxies of consents by or on behalf of a person other than the Board of Directors; or

(4) consummation of a reorganization, merger or consolidation or sale or other disposition of all or substantially all of the assets of the Corporation (a “Business Combination”), in each case, unless, immediately following such Business Combination, (i) all or substantially all of the individuals and entities who were the beneficial owners, respectively, of the Outstanding Corporation Common Stock and Outstanding Corporation Voting Securities immediately prior to such Business Combination beneficially own, directly or indirectly, more than 50% of, respectively, the then outstanding shares of common stock of the Corporation and the combined voting power of the then outstanding voting securities entitled to vote generally in the election of directors, as the case may be, of the corporation resulting from such Business Combination (including, without limitation, a corporation that as a result of such transaction owns the Corporation or all or substantially all of the Corporation’s assets either directly or through one or more subsidiaries) in substantially the same proportions as their ownership, immediately prior to such Business Combination of the Outstanding Corporation Common Stock and Outstanding Corporation Voting Securities, as the case may be, (ii) no Person (excluding any corporation resulting from such Business Combination or any employee benefit plan (or related trust) of the Corporation or such corporation resulting from such Business Combination) beneficially owns, directly or indirectly, 20% or more of, respectively, the then outstanding shares of common stock of the corporation resulting from such Business Combination or the combined voting power of the then outstanding voting securities of such corporation except to the extent that such ownership existed prior to the Business Combination, and (iii) at least a majority of the members of the board of directors of the corporation resulting from such Business Combination were members of the Incumbent Board at the time of the execution of the initial agreement, or of the action of the Board of Directors, providing for such Business Combination; or

(5) approval by the stockholders of a complete liquidation or dissolution of the Corporation.

(b) “Disinterested Director” shall mean a director of the Corporation who is not and was not a party to the proceeding in respect of which indemnification is sought by the claimant.

(c) “Independent Counsel” shall mean a law firm, a member of a law firm, or an independent practitioner, that is experienced in matters of corporation law and neither presently is, nor in the past five (5) years has been, retained to represent: (i) the Corporation or the claimant in any matter material to any such party, or (ii) any other party to the proceeding giving rise to a claim for indemnification hereunder. Notwithstanding the foregoing, the term “Independent Counsel” shall not shall include any person who, under the applicable standards of professional conduct then prevailing, would have a conflict of interest in representing either the Corporation or the claimant in an action to determine the claimant’s rights under this Article XIII.

Section 7. Notices. Any notice, request or other communication required or permitted to be given to the Corporation under this Article XIII shall be in writing and either delivered in person or sent by telecopy or other electronic transmission, overnight mail or courier service, or certified or registered mail, postage or charges prepaid, return copy requested, to the Secretary of the Corporation and shall be effective only upon receipt by the Secretary.

ARTICLE XIV

AMENDMENTS

The Board of Directors shall have the power to adopt, amend or repeal these Bylaws. Bylaws adopted by the Board of Directors may be repealed or changed, and new Bylaws made, by the stockholders, and the stockholders may prescribe that any Bylaw made by them shall not be altered, amended or repealed by the Board of Directors.

Sigilon Therapeutics, Inc. 8-K