QT Imaging (QTI) 8-KEntry into a Material Definitive Agreement

Exhibit 3.1

SECOND AMENDED AND RESTATED

CERTIFICATE OF INCORPORATION

OF

GIGCAPITAL5, INC.

March 4, 2024

GigCapital5, Inc., a corporation organized and existing under the laws of the State of Delaware (the “Corporation”), DOES HEREBY CERTIFY AS FOLLOWS:

ARTICLE I

NAME

The name of the corporation is QT Imaging Holdings, Inc. (the “Corporation”).

ARTICLE II

PURPOSE

The purpose of the Corporation is to engage in any lawful act or activity for which corporations may be organized under the DGCL.

ARTICLE III

REGISTERED AGENT

The address of the Corporation’s registered office in the State of Delaware is 1209 Orange Street, Corporation Trust Center in the City of Wilmington, County of New Castle, State of Delaware, 19801, and the name of the Corporation’s registered agent at such address is The Corporation Trust Company.

ARTICLE IV

CAPITALIZATION

Section 4.1 Authorized Capital Stock. The total number of shares of all classes of capital stock which the Corporation is authorized to issue is 510,000,000 shares, consisting of (a) 500,000,000 shares of common stock, par value $0.0001 per share (the “Common Stock”) and (b) 10,000,000 shares of preferred stock, par value $0.0001 per share (the “Preferred Stock”).

Section 4.2 Preferred Stock. The Preferred Stock may be issued from time to time in one or more series. The Board of Directors of the Corporation (the “Board”) is hereby expressly authorized to provide out of the unissued shares of the Preferred Stock for one or more series of Preferred Stock and to establish from time to time the number of shares to be included in each such series and to fix the voting rights, if any, designations, powers, preferences and relative, participating, optional, special and other rights, if any, of each such series and any qualifications, limitations and restrictions thereof, as shall be stated in the resolution or resolutions adopted by the Board providing for the issuance of such series and included in a certificate of designation (a “Preferred Stock Designation”) filed pursuant to the DGCL, and the Board is hereby expressly vested with the authority to the full extent provided by law, now or hereafter, to adopt any such resolution or resolutions.

Section 4.3 Common Stock.

(a) Voting.

(i) Except as otherwise required by law or this Second Amended and Restated Certificate (including any Preferred Stock Designation), the holders of the shares of Common Stock shall exclusively possess all voting power with respect to the Corporation.

(ii) Except as otherwise required by law or this Second Amended and Restated Certificate (including any Preferred Stock Designation), the holders of shares of Common Stock shall be entitled to one vote for each such share on each matter properly submitted to the stockholders of the Corporation on which the holders of the shares of Common Stock are entitled to vote.

(iii) Except as otherwise required by law or this Second Amended and Restated Certificate (including any Preferred Stock Designation), at any annual or special meeting of the stockholders of the Corporation, the holders of the shares of Common Stock shall have the exclusive right to vote for the election of directors and on all other matters properly submitted to a vote of the stockholders of the Corporation. Notwithstanding the foregoing, except as otherwise required by law or this Second Amended and Restated Certificate (including any Preferred Stock Designation), the holders of the shares of Common Stock shall not be entitled to vote on any amendment to this Second Amended and Restated Certificate (including any amendment to any Preferred Stock Designation) that relates solely to the terms of one or more outstanding series of Preferred Stock if the holders of such affected series of Preferred Stock are entitled, either separately or together with the holders of one or more other such series, to vote thereon pursuant to this Second Amended and Restated Certificate (including any Preferred Stock Designation) or the DGCL.

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(b) Dividends. Subject to applicable law, the rights, if any, of the holders of any outstanding series of the Preferred Stock, the holders of the shares of Common Stock shall be entitled to receive such dividends and other distributions (payable in cash, property or capital stock of the Corporation) when, as and if declared thereon by the Board from time to time out of any assets or funds of the Corporation legally available therefor and shall share equally on a per share basis in such dividends and distributions.

(c) Liquidation, Dissolution or Winding Up of the Corporation. Subject to applicable law, the rights, if any, of the holders of any outstanding series of the Preferred Stock, in the event of any voluntary or involuntary liquidation, dissolution or winding up of the Corporation, after payment or provision for payment of the debts and other liabilities of the Corporation, the holders of the shares of Common Stock shall be entitled to receive all the remaining assets of the Corporation available for distribution to its stockholders, ratably in proportion to the number of shares of Common Stock held by them.

Section 4.4 Rights and Options. The Corporation has the authority to create and issue rights, warrants and options entitling the holders thereof to acquire from the Corporation any shares of its capital stock of any class or classes, with such rights, warrants and options to be evidenced by or in instrument(s) approved by the Board. The Board is empowered to set the exercise price, duration, times for exercise and other terms and conditions of such rights, warrants or options; provided, however, that the consideration to be received for any shares of capital stock issuable upon exercise thereof may not be less than the par value thereof.

ARTICLE V

BOARD OF DIRECTORS

Section 5.1 Board Powers. The business and affairs of the Corporation shall be managed by, or under the direction of, the Board. In addition to the powers and authority expressly conferred upon the Board by statute, this Second Amended and Restated Certificate or the Bylaws of the Corporation (as they may be amended from time to time, “Bylaws”), the Board is hereby empowered to exercise all such powers and do all such acts and things as may be exercised or done by the Corporation, subject, nevertheless, to the provisions of the DGCL, this Second Amended and Restated Certificate, and any Bylaws adopted by the stockholders of the Corporation; provided, however, that no Bylaws hereafter adopted by the stockholders of the Corporation shall invalidate any prior act of the Board that would have been valid if such Bylaws had not been adopted.

Section 5.2 Number, Election and Term.

(a) The number of directors of the Corporation, other than those who may be elected by the holders of one or more series of the Preferred Stock voting separately by class or series, shall be fixed from time to time exclusively by the Board pursuant to a resolution adopted by a majority of the Board.

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(b) Subject to Section 5.5 hereof, the Board shall be divided into three classes, as nearly equal in number as possible and designated Class I, Class II, and Class III. The Board is authorized to assign members of the Board already in office to Class I, Class II, or Class III. The term of the initial Class I Directors shall expire at the first annual meeting of the stockholders of the Corporation following the effectiveness of this Second Amended and Restated Certificate, the term of the initial Class II Directors shall expire at the second annual meeting of the stockholders of the Corporation following the effectiveness of this Second Amended and Restated Certificate, and the term of the initial Class III directors shall expire at the third annual meeting of the stockholders following the effectiveness of this Second Amended and Restated Certificate. At each succeeding annual meeting of the stockholders of the Corporation, beginning with the first annual meeting of the stockholders of the Corporation following the effectiveness of this Second Amended and Restated Certificate, each of the successors elected to replace the class of directors whose term expires at that annual meeting shall be elected for a three year term or until the election and qualification of their respective successors in office, subject to their earlier death, resignation or removal. Subject to Section 5.5 hereof, if the number of directors that constitutes the Board is changed, any increase or decrease shall be apportioned by the Board among the classes so as to maintain the number of directors in each class as nearly equal as possible, but in no case shall a decrease in the number of directors constituting the Board shorten the term of any incumbent director. Subject to the rights of the holders of one or more series of Preferred Stock, voting separately by class or series, to elect directors pursuant to the terms of one or more series of Preferred Stock, the election of directors shall be determined by a plurality of the votes cast by the stockholders present in person or represented by proxy at the meeting and entitled to vote thereon. The Board is hereby expressly authorized, by resolution or resolutions thereof, to assign members of the Board already in office to the aforesaid classes at the time this Second Amended and Restated Certificate (and therefore such classification) becomes effective in accordance with the DGCL.

(c) Subject to Section 5.5 hereof, a director shall hold office until the next annual meeting for the year in which his or her term expires and until his or her successor has been elected and qualified, subject, however, to such director’s earlier death, resignation, retirement, disqualification or removal.

(d) Unless and except to the extent that the Bylaws shall so require, the election of directors need not be by written ballot. The holders of shares of Common Stock shall not have cumulative voting rights.

Section 5.3 Newly Created Directorships and Vacancies. Subject to Section 5.5 hereof, newly created directorships resulting from an increase in the number of directors and any vacancies on the Board resulting from death, resignation, retirement, disqualification, removal or other cause may be filled solely and exclusively by a majority vote of the remaining directors then in office, even if less than a quorum, or by a sole remaining director (and not by stockholders), and any director so chosen shall hold office for the remainder of the full term of the class of directors to which the new directorship was added or in which the vacancy occurred and until his or her successor has been elected and qualified, subject, however, to such director’s earlier death, resignation, retirement, disqualification or removal.

Section 5.4 Removal. Subject to Section 5.5 hereof, any or all of the directors may be removed from office, but only for cause, by the affirmative vote of holders of a majority of the voting power of all then outstanding shares of capital stock of the Corporation entitled to vote generally in the election of directors, voting together as a single class, at a meeting called for that purpose.

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Section 5.5 Preferred Stock—Directors. Notwithstanding any other provision of this Article V, and except as otherwise required by law, whenever the holders of one or more series of the Preferred Stock shall have the right, voting separately by class or series, to elect one or more directors, the term of office, the filling of vacancies, the removal from office and other features of such directorships shall be governed by the terms of such series of the Preferred Stock as set forth in this Second Amended and Restated Certificate (including any Preferred Stock Designation) and such directors shall not be included in any of the classes created pursuant to this Article V unless expressly provided by such terms.

ARTICLE VI

BYLAWS

In furtherance and not in limitation of the powers conferred upon it by law, the Board shall have the power and is expressly authorized to adopt, amend, alter or repeal the Bylaws by the affirmative vote of a majority of the total number of directors present at a regular or special meeting of the Board at which there is a quorum or by unanimous written consent. The Bylaws also may be adopted, amended, altered or repealed by the stockholders of the Corporation; provided, however, that in addition to any vote of the holders of any class or series of capital stock of the Corporation required by law or by this Second Amended and Restated Certificate (including any Preferred Stock Designation), the affirmative vote of the holders of at least a majority of the voting power of all then outstanding shares of capital stock of the Corporation entitled to vote generally in the election of directors, voting together as a single class, shall be required for the stockholders of the Corporation to adopt, amend, alter or repeal the Bylaws; and provided further, however, that no Bylaws hereafter adopted by the stockholders of the Corporation shall invalidate any prior act of the Board that would have been valid if such Bylaws had not been adopted.

ARTICLE VII

SPECIAL MEETINGS OF STOCKHOLDERS; ACTION BY WRITTEN CONSENT

Section 7.1 Special Meetings. Subject to the rights, if any, of the holders of any outstanding series of the Preferred Stock, and to the requirements of applicable law, special meetings of stockholders of the Corporation may be called only by the Chairman of the Board, Chief Executive Officer of the Corporation, or the Board pursuant to a resolution adopted by a majority of the Board, and the ability of the stockholders of the Corporation to call a special meeting is hereby specifically denied. Except as provided in the foregoing sentence, special meetings of stockholders of the Corporation may not be called by another person or persons.

Section 7.2 Advance Notice. Advance notice of stockholder nominations for the election of directors and of business to be brought by stockholders before any meeting of the stockholders of the Corporation shall be given in the manner provided in the Bylaws.

Section 7.3 Action by Written Consent. Except as may be otherwise provided for or fixed pursuant to this Second Amended and Restated Certificate (including any Preferred Stock Designation) relating to the rights of the holders of any outstanding series of Preferred Stock, any action required or permitted to be taken by the stockholders of the Corporation must be effected by a duly called annual or special meeting of such stockholders and may not be effected by written consent of the stockholders of the Corporation.

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ARTICLE VIII

LIMITED LIABILITY; INDEMNIFICATION

Section 8.1 Limitation of Director Liability. A director of the Corporation shall not be personally liable to the Corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except to the extent such exemption from liability or limitation thereof is not permitted under the DGCL as the same exists or may hereafter be amended unless a director violated his or her duty of loyalty to the Corporation or its stockholders, acted in bad faith, knowingly or intentionally violated the law, authorized unlawful payments of dividends, unlawful stock purchases or unlawful redemptions, or derived improper personal benefit from his or her actions as a director. Any amendment, modification or repeal of the foregoing sentence shall not adversely affect any right or protection of a director of the Corporation hereunder in respect of any act or omission occurring prior to the time of such amendment, modification or repeal.

Section 8.2 Indemnification and Advancement of Expenses.

(a) To the fullest extent permitted by applicable law, as the same exists or may hereafter be amended, the Corporation shall indemnify and hold harmless each person who is or was made a party or is threatened to be made a party to or is otherwise involved in any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (a “proceeding”) by reason of the fact that he or she is or was a director or officer of the Corporation or, while a director or officer of the Corporation, is or was serving at the request of the Corporation as a director, officer, employee or agent of another corporation or of a partnership, joint venture, trust, other enterprise or nonprofit entity, including service with respect to an employee benefit plan (an “indemnitee”), whether the basis of such proceeding is alleged action in an official capacity as a director, officer, employee or agent, or in any other capacity while serving as a director, officer, employee or agent, against all liability and loss suffered and expenses (including, without limitation, attorneys’ fees, judgments, fines, ERISA excise taxes and penalties and amounts paid in settlement) reasonably incurred by such indemnitee in connection with such proceeding. The Corporation shall to the fullest extent not prohibited by applicable law pay the expenses (including attorneys’ fees) incurred by an indemnitee in defending or otherwise participating in any proceeding in advance of its final disposition; provided, however, that, to the extent required by applicable law, such payment of expenses in advance of the final disposition of the proceeding shall be made only upon receipt of an undertaking, by or on behalf of the indemnitee, to repay all amounts so advanced if it shall ultimately be determined that the indemnitee is not entitled to be indemnified under this Section 8.2 or otherwise. The rights to indemnification and advancement of expenses conferred by this Section 8.2 shall be contract rights and such rights shall continue as to an indemnitee who has ceased to be a director, officer, employee or agent and shall inure to the benefit of his or her heirs, executors and administrators. Notwithstanding the foregoing provisions of this Section 8.2(a), except for proceedings to enforce rights to indemnification and advancement of expenses, the Corporation shall indemnify and advance expenses to an indemnitee in connection with a proceeding (or part thereof) initiated by such indemnitee only if such proceeding (or part thereof) was authorized by the Board.

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(b) The rights to indemnification and advancement of expenses conferred on any indemnitee by this Section 8.2 shall not be exclusive of any other rights that any indemnitee may have or hereafter acquire under law, this Second Amended and Restated Certificate, the Bylaws, an agreement, vote of stockholders or disinterested directors, or otherwise.

(c) Any repeal or amendment of this Section 8.2 by the stockholders of the Corporation or by changes in law, or the adoption of any other provision of this Second Amended and Restated Certificate inconsistent with this Section 8.2, shall, unless otherwise required by law, be prospective only (except to the extent such amendment or change in law permits the Corporation to provide broader indemnification rights on a retroactive basis than permitted prior thereto), and shall not in any way diminish or adversely affect any right or protection existing at the time of such repeal or amendment or adoption of such inconsistent provision 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 such repeal or amendment or adoption of such inconsistent provision.

(d) This Section 8.2 shall not limit the right of the Corporation, to the extent and in the manner authorized or permitted by law, to indemnify and to advance expenses to persons other than indemnitees.

ARTICLE IX

CORPORATE OPPORTUNITY

Section 9.1 Corporate Opportunities and Non-Employee Directors.

(a) In recognition and anticipation that members of the Board who are not employees of the Corporation (the “Non-Employee Directors”) and their respective Affiliates may now engage and may continue to engage in the same or similar activities or related lines of business as those in which the Corporation, directly or indirectly, may engage and/or other business activities that overlap with or compete with those in which the Corporation, directly or indirectly, may engage, the provisions of this Article IX are set forth to regulate and define the conduct of certain affairs of the Corporation with respect to certain classes or categories of business opportunities as they may involve any of the Non-Employee Directors or their respective Affiliates and the powers, rights, duties and liabilities of the Corporation and its directors, officers and stockholders in connection therewith. For purposes of this Article IX, (i) “Affiliate” shall mean, (a) in respect of each Non-Employee Director, any Person that, directly or indirectly, is controlled by such Non-Employee Director (other than the Corporation and any entity that is controlled by the Corporation) and (b) in respect of the Corporation, any Person that, directly or indirectly, is controlled by the Corporation; and (ii) “Person” shall mean any individual, corporation, general or limited partnership, limited liability company, joint venture, trust, association or any other entity.

(b) No Non-Employee Director (including any Non-Employee Director who serves as an officer of the Corporation in both his or her director and officer capacities) or his or her Affiliates (such Persons being referred to, collectively, as “Identified Persons” and, individually, as an “Identified Person”) shall, to the fullest extent permitted by law, have any duty to refrain from directly or indirectly (1) engaging in the same or similar business activities or lines of

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business in which the Corporation or any of its Affiliates now engages or proposes to engage or (2) otherwise competing with the Corporation or any of its Affiliates, and, to the fullest extent permitted by law, no Identified Person shall be liable to the Corporation or its stockholders or to any Affiliate of the Corporation for breach of any fiduciary duty solely by reason of the fact that such Identified Person engages in any such activities. To the fullest extent permitted by law, the Corporation hereby renounces any interest or expectancy in, or right to be offered an opportunity to participate in, any business opportunity which may be a corporate opportunity for an Identified Person and the Corporation or any of its Affiliates, except as provided in Section 9.1(c) of this Article IX. Subject to said Section 9.1(c) of this Article IX, in the event that any Identified Person acquires knowledge of a potential transaction or other business opportunity which may be a corporate opportunity for itself, herself or himself and the Corporation or any of its Affiliates, such Identified Person shall, to the fullest extent permitted by law, have no duty to communicate or offer such transaction or other business opportunity to the Corporation or any of its Affiliates and, to the fullest extent permitted by law, shall not be liable to the Corporation or its stockholders or to any Affiliate of the Corporation for breach of any fiduciary duty as a stockholder, director or officer of the Corporation solely by reason of the fact that such Identified Person pursues or acquires such corporate opportunity for itself, herself or himself, or offers or directs such corporate opportunity to another Person.

(c) The Corporation does not renounce its interest in any corporate opportunity offered to any Non-Employee Director (including any Non-Employee Director who serves as an officer of this Corporation) if such opportunity is expressly offered to such person solely in his or her capacity as a director or officer of the Corporation, and the provisions of Section 9.1(b) of this Article IX shall not apply to any such corporate opportunity.

(d) In addition to and notwithstanding the foregoing provisions of this Article IX, a corporate opportunity shall not be deemed to be a potential corporate opportunity for the Corporation if it is a business opportunity that (i) the Corporation is unable, financially or legally, or is not contractually permitted to undertake, (ii) from its nature, is not in the line of the Corporation’s business or is of no practical advantage to the Corporation or (iii) is one in which the Corporation has no interest or reasonable expectancy.

(e) To the fullest extent permitted by law, any Person purchasing or otherwise acquiring any interest in any shares of capital stock of the Corporation shall be deemed to have notice of and to have consented to the provisions of this Article IX.

(f) Neither the alteration, amendment, addition to or repeal of this Article IX, nor the adoption of any provision of this Second Amended and Restated Certificate (including any Preferred Stock Designation) inconsistent with this Article IX, shall eliminate or reduce the effect of this Article IX in respect of any corporate opportunity first identified or any other matter occurring, or any cause of action, suit or claim that, but for this Article IX, would accrue or arise, prior to such alteration, amendment, addition, repeal or adoption.

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ARTICLE X

AMENDMENT OF SECOND AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

The Corporation reserves the right at any time and from time to time to amend, alter, change or repeal any provision contained in this Second Amended and Restated Certificate (including any Preferred Stock Designation), and other provisions authorized by the laws of the State of Delaware at the time in force that may be added or inserted, in the manner now or hereafter prescribed by this Second Amended and Restated Certificate and the DGCL; and, except as set forth in Article VIII, all rights, preferences and privileges of whatever nature herein conferred upon stockholders, directors or any other persons by and pursuant to this Second Amended and Restated Certificate in its present form or as hereafter amended are granted subject to the right reserved in this Article X.

ARTICLE XI

EXCLUSIVE FORUM FOR CERTAIN LAWSUITS

Section 11.1 Forum. Unless the Corporation consents in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware shall be the sole and exclusive forum for any stockholder (including a beneficial owner) to bring (i) any derivative action or proceeding brought on behalf of the Corporation, (ii) any action asserting a claim of breach of a fiduciary duty owed by any director, officer or other employee of the Corporation to the Corporation or the Corporation’s stockholders, (iii) any action asserting a claim against the Corporation, its directors, officers or employees arising pursuant to any provision of the DGCL or this Second Amended and Restated Certificate or the Bylaws, or (iv) any action asserting a claim against the Corporation, its directors, officers or employees governed by the internal affairs doctrine and, if brought outside of Delaware, the stockholder bringing the suit will be deemed to have consented to service of process on such stockholder’s counsel except any action (A) as to which the Court of Chancery in the State of Delaware determines that there is an indispensable party not subject to the jurisdiction of the Court of Chancery (and the indispensable party does not consent to the personal jurisdiction of the Court of Chancery within ten days following such determination), (B) which is vested in the exclusive jurisdiction of a court or forum other than the Court of Chancery, or (C) for which the Court of Chancery does not have subject matter jurisdiction. Notwithstanding the foregoing, the provisions of this Section 11.1 will not apply to suits brought to enforce any liability or duty created by the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction. Notwithstanding the foregoing, the federal district courts of the United States of America, to the fullest extent permitted by law, shall be the sole and exclusive forum for the resolution of any action asserting a cause of action arising under the Securities Act. Any person or entity purchasing or otherwise acquiring any interest in any security of the Corporation shall be deemed to have notice of and consented to the provisions of this Section 11.1.

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Section 11.2 Consent to Jurisdiction. If any action the subject matter of which is within the scope of Section 11.1 immediately above is filed in a court other than a court located within the State of Delaware (a “Foreign Action”) in the name of any stockholder, such stockholder shall be deemed to have consented to (i) the personal jurisdiction of the state and federal courts located within the State of Delaware in connection with any action brought in any such court to enforce Section 11.1 immediately above (an “FSC Enforcement Action”) and (ii) having service of process made upon such stockholder in any such FSC Enforcement Action by service upon such stockholder’s counsel in the Foreign Action as agent for such stockholder.

ARTICLE XII

SEVERABILITY

If any provision or provisions (or any part thereof) of this Second Amended and Restated Certificate shall be held to be invalid, illegal or unenforceable as applied to any person, entity or circumstance for any reason whatsoever, then, to the fullest extent permitted by law, (i) the validity, legality and enforceability of such provisions in any other circumstance and of the remaining provisions of this Second Amended and Restated Certificate (including, without limitation, each portion of any paragraph of this Second Amended and Restated Certificate containing any such provision held to be invalid, illegal or unenforceable that is not itself held to be invalid, illegal or unenforceable) and the application of such provision to other persons or entities and circumstances shall not in any way be affected or impaired thereby, and (ii) the provisions of this Second Amended and Restated Certificate (including, without limitation, each portion of any paragraph of this Second Amended and Restated Certificate containing any such provision held to be invalid, illegal or unenforceable) shall be construed so as to permit the Corporation to protect its directors, officers, employees and agents from personal liability in respect of their good faith service or for the benefit of the Corporation to the fullest extent permitted by law.

[Signature page follows.]

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IN WITNESS WHEREOF, GigCapital5, Inc. has caused this Second Amended and Restated Certificate to be duly executed and acknowledged in its name and on its behalf by an authorized officer as of the date first set forth above.

[Signature Page to Second Amended and Restated Certificate of Incorporation]