Exhibit 3.5

BY-LAWS

OF

EYEPOINT PHARMACEUTICALS, INC.

Section 1. LAW, CERTIFICATE OF INCORPORATION AND BY-LAWS

1.1. These by-laws are subject to the certificate of incorporation of the corporation. In these by-laws, references to law, the certificate of incorporation and by-laws mean the law, the provisions of the certificate of incorporation and the by-laws as from time to time in effect.

Section 2. STOCKHOLDERS

2.1. Annual Meetings. The annual meeting of stockholders shall be held at such location within or without the state of Delaware as may be determined from time to time by the board of directors on the second Thursday in November in each year, unless that day be a legal holiday at the place where the meeting is to be held, in which case the meeting shall be held at the same hour on the next succeeding day not a legal holiday, or at such other date and time as may be determined from time to time by the board of directors and stated in the notice of the meeting. At an annual meeting of the stockholders, only such business shall be conducted as shall have been properly brought before the meeting as (a) specified in the notice of meeting (or any supplement thereto) given by or at the direction of the board of directors, (b) otherwise properly brought before the meeting by or at the direction of the board of directors, or (c) otherwise properly brought before the meeting by a stockholder by the stockholder giving timely notice thereof in writing to the secretary of the corporation. To be timely, a stockholder’s notice must be received at the principal executive offices of the corporation: (1) not less than 60 days in advance of such meeting if such meeting is to be held on a day which is within 30 days preceding the anniversary of the previous year’s annual meeting or 90 days in advance of such meeting if such meeting is to be held on or after the anniversary of the previous year’s annual meeting; and (2) with respect to any other annual meeting of stockholders, on or before the close of business on the 15th day following the earliest date of public disclosure of the date of such meeting. For purposes of this section, the date of public disclosure of a meeting shall include, but not be limited to, the date on which disclosure of the date of the meeting is made in a press release reported by the Dow Jones News Services, Associated Press or a comparable national news service, or in a document publicly filed by the corporation with the Securities and Exchange Commission pursuant to Sections 13, 14 or 15(d) (or the rules and regulations thereunder) of the Securities Exchange Act of 1934, as amended. A stockholder’s notice to the secretary shall set forth as to each matter the stockholder proposes to bring before the annual meeting (a) a brief description of the business desired to be brought before the annual meeting and the reasons for conducting such business at the annual meeting, (b) the name, age and

business and residential address, as they appear on the corporation’s records, of the stockholder proposing such business, (c) the class and number of shares of the corporation which are beneficially owned by the stockholder, and (d) any material interest of the stockholder in such business. Notwithstanding anything in the by-laws to the contrary, no business shall be conducted at an annual meeting except in accordance with the procedures set forth herein. The chairperson of the annual meeting shall, if the facts warrant, determine and declare to the meeting that business was not properly brought before the meeting and in accordance with the provisions hereof 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.

2.2. Nominations. Subject to the rights of any class or series of stock having a preference over the common stock as to dividends or upon liquidation to elect directors under specified circumstances, nominations for the election of directors may be made by the board of directors or a committee appointed by the board of directors or by any stockholder entitled to vote in the election of directors generally. However, any stockholder entitled to vote in the election of directors generally may nominate one or more persons for election as director at a meeting only if timely written notice of such stockholder’s intent to make such nomination or nominations has been given, either by personal delivery or by United States mail, postage prepaid, to the secretary of the corporation. To be timely, a stockholder’s notice must be received at the principal executive offices of the corporation: (1) not less than 60 days in advance of such meeting if such meeting is to be held on a day which is within 30 days preceding the anniversary of the previous year’s annual meeting or 90 days in advance of such meeting if such meeting is to be held on or after the anniversary of the previous year’s annual meeting; and (2) with respect to any other annual meeting of stockholders, on or before the close of business on the 15th day following the earliest date of public disclosure of the date of such meeting. For purposes of this section, the date of public disclosure of a meeting shall include, but not be limited to, the date on which disclosure of the date of the meeting is made in a press release reported by the Dow Jones News Services, Associated Press or a comparable national news service or in a document publicly filed by the corporation with the Securities and Exchange Commission pursuant to Sections 13, 14 or 15(d) (or the rules and regulations thereunder) of the Securities Exchange Act of 1934, as amended. Each such notice shall set forth: (a) the name, age and business and residential address of the stockholder who intends to make the nomination and of the person or persons to be nominated; (b) a representation that the stockholder is a holder of record of stock of the corporation entitled to vote at such meeting and intends to appear in person or by proxy at the meeting to nominate the person or persons (naming such person or persons) pursuant to which the nomination or nominations are to be made by the stockholder; (c) such other information regarding each nominee proposed by such stockholder as would be required to be included in a proxy statement filed pursuant to the proxy rules of the Securities and Exchange Commission, had the nominee been nominated, or intended to be nominated, by the board of directors; and (e) the written consent of each nominee to serve as a director of the corporation if so elected. The chairperson of the meeting shall refuse to acknowledge the nomination of any person not made in compliance with the foregoing procedures.

 

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2.3. Special Meetings. A special meeting of the stockholders may be called at any time by the chairperson of the board, if any, the president, if any, or the board of directors. A special meeting of the stockholders shall be called by the secretary, or in the case of the death, absence, incapacity or refusal of the secretary, by an assistant secretary or some other officer, upon application of a majority of the directors. Any such application shall state the purpose or purposes of the proposed meeting. Any such call shall state the place, date, hour, and purposes of the meeting.

2.4. Place of Meeting. All meetings of the stockholders for the election of directors or for any other purpose shall be held at such place within or without the State of Delaware as may be determined from time to time by the chairperson of the board, if any, the president, if any, or the board of directors. Any adjourned session of any meeting of the stockholders shall be held at the place designated in the vote of adjournment.

2.5. Notice of Meetings. Except as otherwise provided by law, a written notice of each meeting of stockholders stating the place, if any, date and hour thereof, 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, in the case of a special meeting, the purposes for which the meeting is called, shall be given not less then ten nor more than sixty days before the meeting, to each stockholder entitled to vote thereat, and to each stockholder who, by law, by the certificate of incorporation or by these by-laws, is entitled to notice. If mailed, notice to stockholders shall be deemed given when deposited in the United States mail, postage prepaid, and addressed to such stockholder at such stockholder’s address as it appears in the records of the corporation. Such notice to stockholders may be given by electronic transmission in the manner provided by Delaware law. Such notice shall be given by the secretary, or by an officer or person designated by the board of directors, or in the case of a special meeting, by the officer calling the meeting. As to any adjourned session of any meeting of stockholders, notice of the adjourned meeting need not be given if the time and place thereof are announced at the meeting at which the adjournment was taken, except that if the adjournment is for more than thirty days or if after the adjournment a new record date is set for the adjourned session, notice of any such adjourned session of the meeting shall be given in the manner heretofore described. A written waiver of any notice, signed by a stockholder, or a waiver by electronic transmission by a stockholder, whether given before or after the time of the meeting, shall be deemed equivalent to the notice required to be given to such person. Attendance at any meeting shall constitute waiver of notice, except attendance for the sole purpose of objecting at the beginning of the meeting to the transaction of any business because the meeting is not lawfully called or convened. Neither the business to be transacted at, nor the purpose of, any meeting of the stockholders or any adjourned session thereof need be specified in any written waiver of notice.

2.6. Quorum of Stockholders. At any meeting of the stockholders, a quorum as to any matter shall consist of one-third of the votes entitled to be cast on the matter, except where a larger quorum is required by law, by the certificate of incorporation or by these by-laws. Any meeting may be adjourned from time to time by a majority of the votes properly cast upon the question, whether or not a quorum is present. If a quorum is present at an original meeting, a

 

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quorum need not be present at an adjourned session of that meeting. Shares of its own stock belonging to the corporation or to another corporation, if a majority of the shares entitled to vote in the election of directors of such other corporation is held, directly or indirectly, by the corporation, shall neither be entitled to vote nor be counted for quorum purposes; provided, however, that the foregoing shall not limit the right of any corporation to vote stock, including but not limited to its own stock, held by it in a fiduciary capacity.

2.7. Action by Vote. When a quorum is present at any meeting, a plurality of the votes properly cast for election to any office shall elect to such office and a majority of the votes properly cast upon any question other than an election to an office shall decide the question, except when a larger vote is required by law, by the certificate of incorporation or by these by-laws. No ballot shall be required for any election unless requested by a stockholder present or represented at the meeting and entitled to vote in the election.

2.8. Proxy Representation. Every stockholder may authorize another person or persons to act for such stockholder by proxy in all matters in which a stockholder is entitled to participate, whether by waiving notice of any meeting, objecting to or voting or participating at a meeting, or expressing consent or dissent without a meeting. Every proxy must be signed by the stockholder or by such stockholder’s attorney-in-fact. No proxy shall be voted or acted upon after three years from its date unless such proxy provides for a longer period. A duly executed proxy shall be irrevocable if it states that it is irrevocable and, if, and only as long as, it is coupled with an interest sufficient in law to support an irrevocable power. A proxy may be made irrevocable regardless of whether the interest with which it is coupled is an interest in the stock itself or an interest in the corporation generally. The authorization of a proxy may but need not be limited to specified action, provided, however, that if a proxy limits its authorization to a meeting or meetings of stockholders, unless otherwise specifically provided such proxy shall entitle the holder thereof to vote at any adjourned session but shall not be valid after the final adjournment thereof.

2.9. Inspectors. The directors or the person presiding at the meeting may, and shall if required by applicable law, appoint one or more inspectors of election and any substitute inspectors to act at the meeting or any adjournment thereof. Each inspector, before entering upon the discharge of such inspector’s 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 such inspector’s 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, 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 inspectors shall make a report in writing of any challenge, question or matter determined by them and execute a certificate of any fact found by them.

 

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2.10. List of Stockholders. The secretary shall prepare and make, at least ten days before every meeting of stockholders, a complete list of the stockholders entitled to vote at such meeting, arranged in alphabetical order and showing the address of each stockholder and the number of shares registered in such stockholder’s name. The stock ledger shall be the only evidence as to who are stockholders entitled to examine such list or to vote in person or by proxy at such meeting.

Section 3. BOARD OF DIRECTORS

3.1. Number. The corporation shall have one or more directors, the number of directors to be determined from time to time by vote of a majority of the directors then in office. Except in connection with the election of directors at the annual meeting of stockholders, the number of directors may be decreased only to eliminate vacancies by reason of death, resignation or removal of one or more directors. No director need be a stockholder.

3.2. Tenure. Except as otherwise provided by law, by the certificate of incorporation or by these by-laws, each director shall hold office until the next annual meeting and until such director’s successor is elected and qualified, or until he sooner dies, resigns, is removed or becomes disqualified.

3.3. Powers. The business and affairs of the corporation shall be managed by or under the direction of the board of directors who shall have and may exercise all the powers of the corporation and do all such lawful acts and things as are not by law, the certificate of incorporation or these by-laws directed or required to be exercised or done by the stockholders.

3.4. Vacancies. Vacancies and any newly created directorships resulting from any increase in the number of directors may be filled by vote of the holders of the particular class or series of stock entitled to elect such director at a meeting called for the purpose, or by a majority of the directors then in office, although less than a quorum, or by a sole remaining director, in each case elected by the particular class or series of stock entitled to elect such directors. When one or more directors shall resign from the board, effective at a future date, a majority of the directors then in office, including those who have resigned, who were elected by the particular class or series of stock entitled to elect such resigning director or directors shall have power to fill such vacancy or vacancies, the vote or action by writing thereon to take effect when such resignation or resignations shall become effective. The directors shall have and may exercise all their powers notwithstanding the existence of one or more vacancies in their number, subject to any requirements of law or of the certificate of incorporation or of these by-laws as to the number of directors required for a quorum or for any vote or other actions.

3.5. Committees. The board of directors may, by vote of a majority of the whole board, (a) designate, change the membership of or terminate the existence of any committee or committees, each committee to consist of one or more of the directors; (b) designate one or more directors as alternate members of any such committee who may replace any absent or disqualified member at any meeting of the committee; and (c) determine the extent to which each

 

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such committee shall have and may exercise the powers of the board of directors in the management of the business and affairs of the corporation, including the power to authorize the seal of the corporation to be affixed to all papers which require it and the power and authority to declare dividends or to authorize the issuance of stock; excepting, however, such powers which by law, by the certificate of incorporation or by these by-laws they are prohibited from so delegating. In the absence or disqualification of any member of such committee and such member’s alternate, if any, the member or members thereof present at any meeting and not disqualified from voting, whether or not constituting a quorum, may unanimously appoint another member of the board of directors to act at the meeting in the place of any such absent or disqualified member. Except as the board of directors may otherwise determine, any committee may make rules for the conduct of its business, but unless otherwise provided by the board or such rules, its business shall be conducted as nearly as may be in the same manner as is provided by these by-laws for the conduct of business by the board of directors.

3.6. Regular Meetings. Regular meetings of the board of directors may be held without call or notice at such places within or without the State of Delaware and at such times as the board may from time to time determine, provided that notice of the first regular meeting following any such determination shall be given to absent directors. A regular meeting of the directors may be held without call or notice immediately after and at the same place as the annual meeting of stockholders.

3.7. Special Meetings. Special meetings of the board of directors may be held at any time and at any place within or without the State of Delaware designated in the notice of the meeting, when called by the chairperson of the board, if any, the president, if any, or by one-third or more in number of the directors, notice thereof being given to each director by the secretary or by the chairperson of the board, if any, the president, if any, or any one of the directors calling the meeting.

3.8. Notice. It shall be reasonable and sufficient notice to a director to send notice by mail at least forty-eight hours or by delivery service at least twenty-four hours before the meeting addressed to such director at such director’s usual or last known business or residence address or to give notice to such director in person or by telephone, facsimile telecommunication or electronic mail at least twenty-four hours before the meeting. A written waiver of any notice, signed by a director, or a waiver by electronic transmission by a director, whether given before or after the time of the meeting, shall be deemed equivalent to the notice required to be given to such person. Attendance at any meeting shall constitute waiver of notice. Neither notice of a meeting nor a waiver of a notice need specify the purposes of the meeting.

3.9. Quorum. Except as may be otherwise provided by law, by the certificate of incorporation or by these by-laws, at any meeting of the directors a majority of the directors then in office shall constitute a quorum; a quorum shall not in any case be less than one-third of the total number of directors constituting the whole board. Any meeting may be adjourned from time to time by a majority of the votes cast upon the question, whether or not a quorum is present, and the meeting may be held as adjourned without further notice.

 

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3.10. Action by Vote. Except as may be otherwise provided by law, by the certificate of incorporation or by these by-laws, when a quorum is present at any meeting, the vote of a majority of the directors present shall be the act of the board of directors.

3.11. Action Without a Meeting. Any action required or permitted to be taken at any meeting of the board of directors or a committee thereof may be taken without a meeting if all the members of the board or of such committee, as the case may be, consent thereto in writing, and such writing or writings are filed with the records of the meetings of the board or of such committee. Such consent shall be treated for all purposes as the act of the board or of such committee, as the case may be.

3.12. Participation in Meetings by Conference Telephone. Members of the board of directors, or any committee designated by such board, may participate in a meeting of such board or committee by means of conference telephone or similar communications equipment by means of which all persons participating in the meeting can hear each other or by any other means permitted by law. Such participation shall constitute presence in person at such meeting.

3.13. Compensation. In the discretion of the board of directors, each director may be paid such fees for such director’s services as director and be reimbursed for such director’s reasonable expenses incurred in the performance of such director’s duties as director as the board of directors from time to time may determine. Nothing contained in this section shall be construed to preclude any director from serving the corporation in any other capacity and receiving reasonable compensation therefor.

3.14. Interested Directors and Officers.

(a) No contract or transaction between the corporation and one or more of its directors or officers, or between the corporation and any other corporation, partnership, association, or other organization in which one or more of the corporation’s directors or officers are directors or officers, or have a financial interest, shall be void or voidable solely for this reason, or solely because the director or officer is present at or participates in the meeting of the board or committee thereof which authorizes the contract or transaction, or solely because the votes of such director or officer are counted for such purpose, if:

(1) The material facts as to such director’s or such officer’s relationship or interest and as to the contract or transaction are disclosed or are known to the board of directors or the committee, and the board or committee in good faith authorizes the contract or transaction by the affirmative votes of a majority of the disinterested directors, even though the disinterested directors be less than a quorum; or

(2) The material facts as to such director’s or such officer’s relationship or interest and as to the contract or transaction are disclosed or are known to the stockholders entitled to vote thereon, and the contract or transaction is specifically approved in good faith by vote of the stockholders; or

 

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(3) The contract or transaction is fair as to the corporation as of the time it is authorized, approved or ratified, by the board of directors, a committee thereof, or the stockholders.

(b) Common or interested directors may be counted in determining the presence of a quorum at a meeting of the board of directors or of a committee which authorizes the contract or transaction.

Section 4. OFFICERS AND AGENTS

4.1. Enumeration; Qualification. The corporation shall have such officers as the board of directors from time to time may in its discretion elect or appoint. The corporation may also have such agents, if any, as the board of directors from time to time may in its discretion choose. Any officer may be but none need be a director or stockholder. Any two or more offices may be held by the same person. Any officer may be required by the board of directors to secure the faithful performance of such officer’s duties to the corporation by giving bond in such amount and with sureties or otherwise as the board of directors may determine.

4.2. Powers. Subject to law, to the certificate of incorporation and to the other provisions of these by-laws, each officer shall have, in addition to the duties and powers herein set forth, such duties and powers as are commonly incident to such officer’s office and such additional duties and powers as the board of directors may from time to time designate.

4.3. Election. The officers may be elected by the board of directors at their first meeting following the annual meeting of the stockholders or at any other time. At any time or from time to time the directors may delegate to any officer their power to elect or appoint any other officer or any agents.

4.4. Tenure. Each officer shall hold office until the first meeting of the board of directors following the next annual meeting of the stockholders and until such officer’s respective successor is chosen and qualified, unless a shorter period shall have been specified by the terms of such officer’s election or appointment, or in each case until he sooner dies, resigns, is removed or becomes disqualified. Each agent shall retain such agent’s authority at the pleasure of the directors, or the officer by whom such agent was appointed or by the officer who then holds agent appointive power.

Section 5. RESIGNATIONS AND REMOVALS

5.1. Any director or officer may resign at any time by delivering his or her resignation in writing to the chairperson of the board, if any, the president, if any, or the secretary or to a meeting of the board of directors. Such resignation shall be effective upon receipt unless specified to be effective at some other time, and without in either case the necessity of its being accepted unless the resignation shall so state. Except as may be otherwise provided by law, by the certificate of incorporation or by these by-laws, a director (including persons elected by stockholders or directors to fill vacancies in the board) may be removed from office with or

 

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without cause by the vote of the holders of a majority of the issued and outstanding shares of the particular class or series entitled to vote in the election of such directors. The board of directors may at any time remove any officer either with or without cause. The board of directors may at any time terminate or modify the authority of any agent.

Section 6. VACANCIES

6.1. If the office of any officer becomes vacant, any person or body empowered to elect or appoint that officer may choose a successor. Each such successor shall hold office for the unexpired term, and until his or her successor is chosen and qualified or in each case until he or she sooner dies, resigns, is removed or becomes disqualified. Any vacancy of a directorship shall be filled as specified in Section 3.4 of these by-laws.

Section 7. CAPITAL STOCK

7.1. Stock Certificates and Uncertificated Shares. Shares shall be represented by certificates, provided that the board of directors may provide by resolution or resolutions that some or all of any or all classes or series of its stock shall be uncertificated shares. Any such resolution shall not apply to shares represented by a certificate until such certificate is surrendered. Every holder of stock represented by certificates shall be entitled to have a certificate, in such form, as shall, in conformity to law, the certificate of incorporation and the by-laws, be prescribed from time to time by the board of directors and signed by, or in the name of the corporation by the chairperson or vice-chairperson of the board of directors, or the president or vice-president, and by the treasurer or an assistant treasurer, or the secretary or an assistant secretary of such corporation representing the number of shares registered in certificate form. Any or all the signatures on the certificate may be a facsimile. 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 such person were such officer, transfer agent or registrar at the date of issue.

7.2. Loss of Certificates. In the case of the alleged theft, loss, destruction or mutilation of a certificate of stock, a duplicate certificate or uncertificated shares may be issued in place thereof, upon such terms, including receipt of a bond sufficient to indemnify the corporation against any claim on account thereof, as the board of directors may prescribe.

Section 8. TRANSFER OF SHARES OF STOCK

8.1. Transfer on Books. Subject to the restrictions, if any, stated or noted on a stock certificate or, in the case of uncertificated shares, contained in the notice or notices sent pursuant to Delaware law, shares of stock may be transferred on the books of the corporation by the surrender to the corporation or its transfer agent of the certificate therefor properly endorsed or accompanied by a written assignment and power of attorney properly executed, with necessary transfer stamps affixed, and with such proof of the authenticity of signature as the board of

 

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directors or the transfer agent of the corporation may reasonably require, or in such manner as shall be determined by the board of directors from time to time with respect to uncertificated shares. Except as may be otherwise required by law, by the certificate of incorporation or by these by-laws, the corporation shall be entitled to treat the record holder of stock as shown on its books as the owner of such stock for all purposes, including the payment of dividends and the right to receive notice and to vote or to give any consent with respect thereto and to be held liable for such calls and assessments, if any, as may lawfully be made thereon, regardless of any transfer, pledge or other disposition of such stock until the shares have been properly transferred on the books of the corporation.

It shall be the duty of each stockholder to notify the corporation of such stockholder’s post office address.

8.2. Record Date. 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 sixty nor less than ten days before the date of such meeting. If no such record date is fixed by the board of directors, the record date for determining the 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.

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 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 which record date shall be not more than sixty days prior to such payment, exercise or other action. If no such 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.

Section 9. CORPORATE SEAL

9.1. Subject to alteration by the directors, the seal of the corporation shall consist of a flat-faced circular die with the word “Delaware” and the name of the corporation cut or engraved thereon, together with such other words, dates or images as may be approved from time to time by the directors.

 

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Section 10. EXECUTION OF PAPERS

10.1. Except as the board of directors may generally or in particular cases authorize the execution thereof in some other manner, all deeds, leases, transfers, contracts, bonds, notes, checks, drafts or other obligations made, accepted or endorsed by the corporation shall be signed by such officers as are designated by the board of directors.

Section 11. FISCAL YEAR

11.1. The fiscal year of the corporation shall end on June 30.

Section 12. AMENDMENTS

12.1. These by-laws may be adopted, amended or repealed by vote of a majority of the directors then in office or by vote of a majority of the voting power of the stock outstanding and entitled to vote. Any by-law, whether adopted, amended or repealed by the stockholders or directors, may be amended or reinstated by the stockholders or the directors.

 

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