Exhibit 3.1

CERTIFICATE OF INCORPORATION

OF

ORIGIN MATERIALS, INC.

ARTICLE I

The name of this corporation is Origin Materials, Inc. (the “Company”).

ARTICLE II

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

ARTICLE III

The purpose of the Company is to engage in any lawful act or activity for which a corporation may be organized under the General Corporation Law of the State of Delaware (as it now exists or may hereafter be amended and supplemented, the “DGCL”). The Company is being incorporated in connection with the domestication of Artius Acquisition Inc., a Cayman Islands exempted company (“Artius Acquisition”), as a Delaware corporation (the “Domestication”), and this Certificate of Incorporation is being filed simultaneously with the Certificate of Corporate Domestication of Artius Acquisition. This Certificate of Incorporation shall be effective at 5:15 p.m. Eastern Time on June 24, 2021, concurrent with the effectiveness of the Certificate of Corporate Domestication of Artius Acquisition.

ARTICLE IV

A. Prior to the effectiveness of this Certificate of Incorporation, the Company was a Cayman Islands exempted company, which had authorized share capital consisting of 1,000,000 preference shares, par value $0.0001 per share (“Predecessor Preference Shares”), 400,000,000 Class A ordinary shares, par value $0.0001 per share (the “Predecessor Class A Ordinary Shares”) and 50,000,000 Class B ordinary shares, par value $0.0001 per share (the “Predecessor Class B Ordinary Shares”). Immediately upon the effectiveness of this Certificate of Incorporation, (i) the Predecessor Preference Shares issued and outstanding or held as treasury stock, automatically and without further action by any stockholder, were reclassified as, and became, shares of Preferred Stock (as defined below), (ii) the Predecessor Class A Ordinary Shares issued and outstanding or held as treasury stock, automatically and without further action by any stockholder, were reclassified as, and became, shares of Class A Common Stock (as defined below) and (iii) the Predecessor Class B Ordinary Shares issued and outstanding or held as treasury stock, automatically and without further action by any stockholder, were reclassified as, and became, shares of Class B Common Stock (as defined below). As a result, the total number of shares of all classes of stock that the Company is authorized to issue is 451,000,000 shares of stock, consisting of (i) 1,000,000 shares of Preferred Stock, par value $0.0001 per share (“Preferred Stock”), (ii) 450,000,000 shares of common stock (“Common Stock”), including (a) 400,000,000 shares of Class A common stock, par value $0.0001 (“Class A Common Stock”) and (b) 50,000,000 shares of Class B common stock, par value $0.0001 (“Class B Common Stock”).

B. The Preferred Stock may be issued from time to time in one or more series. The Board of Directors of the Company (the “Board of Directors”) is hereby expressly authorized to provide for the issue of all or any of the shares of the Preferred Stock in one or more series, and to fix the number of shares and to determine or alter for each such series, such voting powers, full or limited, or no voting powers, and such designation, preferences, and relative, participating, optional, or other rights and such qualifications, limitations, or restrictions thereof, as shall be stated and expressed in the resolution or resolutions adopted

by the Board of Directors providing for the issuance of such shares and as may be permitted by the DGCL. The Board of Directors is also expressly authorized to increase or decrease the number of shares of any series subsequent to the issuance of shares of that series, but not below the number of shares of such series then outstanding. In case the number of shares of any series shall be decreased in accordance with the foregoing sentence, the shares constituting such decrease shall resume the status that they had prior to the adoption of the resolution originally fixing the number of shares of such series. The number of authorized shares of Preferred Stock may be increased or decreased (but not below the number of shares thereof then outstanding) by the affirmative vote of the holders of a majority of the voting power of the stock of the Company entitled to vote thereon, without a separate vote of the holders of the Preferred Stock, or of any series thereof, unless a vote of any such holders is required pursuant to the terms of any certificate of designation filed with respect to any series of Preferred Stock.

C. Each outstanding share of Common Stock shall entitle the holder thereof to one vote on each matter properly submitted to the stockholders of the Company for their vote; provided, however, that, except as otherwise required by law, holders of Common Stock shall not be entitled to vote on any amendment to this Certificate of Incorporation (including any certificate of designation filed with respect to any series of Preferred Stock) that relates solely to the terms of one or more outstanding series of Preferred Stock if the holders of such affected series are entitled, either separately or together as a class with the holders of one or more other such series, to vote thereon by law or pursuant to this Certificate of Incorporation (including any certificate of designation filed with respect to any series of Preferred Stock) or the DGCL.

D. Subject to the rights of the holders of any outstanding series of Preferred Stock, the holders of shares of Common Stock shall be entitled to receive any dividends to the extent permitted by law when, as and if declared by the Board of Directors of the Company.

E. Upon the dissolution, liquidation or winding up of the Company, subject to the rights of the holders of any outstanding series of Preferred Stock, the holders of shares of Common Stock shall be entitled to receive the assets of the Company available for distribution to its stockholders ratably in proportion to the number of shares held by them. For the avoidance of doubt, a dissolution, liquidation or winding up shall not be deemed to be occasioned by or to include, without limitation, any voluntary consolidation, reorganization, conversion or merger of the Company with or into any other corporation or entity or other corporation or entities or a sale, lease, transfer, exchange or conveyance of all or a part of the Company’s assets.

ARTICLE V

For the management of the business and for the conduct of the affairs of the Company, and in further definition, limitation and regulation of the powers of the Company, of its directors and of its stockholders or any class thereof, as the case may be, it is further provided that:

A. MANAGEMENT OF BUSINESS. The management of the business and the conduct of the affairs of the Company shall be vested in its Board of Directors. The number of directors which shall constitute the Board of Directors shall be fixed exclusively by resolutions adopted by a majority of the authorized number of directors constituting the Board of Directors.

B. ELECTION OF BOARD OF DIRECTORS.

1. Subject to the rights of the holders of any series of Preferred Stock to elect additional directors under specified circumstances, from the effective date of this Certificate of Incorporation (the “Effective Date”) until the completion of the fourth annual meeting of stockholders to occur after the Effective Date, the directors shall be divided into three classes designated as Class I, Class II and Class III, respectively. Each class shall consist, as nearly as may be possible, of one-third of the total

number of directors constituting the entire Board of Directors. If the number of directors is changed, any increase or decrease shall be apportioned among the classes so as to maintain the number of directors in each class as nearly equal as possible, and any additional director of any class elected to fill a vacancy resulting from an increase in such class or from the removal from office, death, disability, resignation or disqualification of a director or other cause shall hold office for a term that shall coincide with the remaining term of that class, but in no case will a decrease in the number of directors have the effect of removing or shortening the term of any incumbent director. The Board of Directors is authorized to assign members of the Board of Directors already in office to such classes at the time the classification becomes effective. The term of the initial Class I directors shall terminate on the date of the first annual meeting of stockholders to occur after the Effective Date; the term of the initial Class II directors shall terminate on the date of the second annual meeting of stockholders to occur after the Effective Date; and the term of the initial Class III directors shall terminate on the date of the third annual meeting of stockholders to occur after the Effective Date, or, in each case, upon such director’s earlier death, resignation or removal. Each Class I director elected at the first annual meeting of stockholders to occur after the Effective Date shall hold office until the fourth annual meeting of stockholders to occur after the Effective Date and each Class I director elected at the fourth annual meeting of stockholders to occur after the Effective Date shall hold office until the fifth annual meeting of stockholders to occur after the Effective Date and, in each case, until his or her respective successor shall have been duly elected and qualified or until his or her earlier resignation or removal. Each Class II director elected at the second annual meeting of stockholders to occur after the Effective Date and each Class III director elected at the third annual meeting of stockholders to occur after the Effective Date shall hold office until the fifth annual meeting of stockholders to occur after the Effective Date and, in each case, until his or her respective successor shall have been duly elected and qualified or until his or her earlier resignation or removal. Commencing with the fifth annual meeting of stockholders to occur after the Effective Date, each director shall be elected annually and shall hold office until the next annual meeting of stockholders and until his or her respective successor shall have been duly elected and qualified or until his or her earlier resignation or removal. Pursuant to such procedures, effective as of the conclusion of the fourth annual meeting of stockholders to occur after the Effective Date, the Board of Directors will no longer be classified under Section 141(d) of the DGCL and directors shall no longer be divided into three classes.

2. At any time that applicable law prohibits a classified board as described in Section B.1. of this Article V, all directors shall be elected at each annual meeting of stockholders to hold office until the next annual meeting. The directors of the Company need not be elected by written ballot unless the Bylaws so provide.

3. No stockholder entitled to vote at an election for directors may cumulate votes to which such stockholder is entitled unless required by applicable law at the time of such election. During such time or times that applicable law requires cumulative voting, every stockholder entitled to vote at an election for directors may cumulate such stockholder’s votes and give one candidate a number of votes equal to the number of directors to be elected multiplied by the number of votes to which such stockholder’s shares are otherwise entitled, or distribute the stockholder’s votes on the same principle among as many candidates as such stockholder thinks fit. No stockholder, however, shall be entitled to so cumulate such stockholder’s votes unless (i) the names of such candidate or candidates have been placed in nomination prior to the voting and (ii) the stockholder has given notice at the meeting, prior to the voting, of such stockholder’s intention to cumulate such stockholder’s votes. If any stockholder has given proper notice to cumulate votes, all stockholders may cumulate their votes for any candidates who have been properly placed in nomination. Under cumulative voting, the candidates receiving the highest number of votes, up to the number of directors to be elected, are elected.

4. Notwithstanding the foregoing provisions of this section, each director shall serve until his or her successor is duly elected and qualified or until his or her earlier death, resignation or removal. No decrease in the number of directors constituting the Board of Directors shall shorten the term of any incumbent director.

5. Notwithstanding the foregoing, whenever the holders of any one or more classes or series of Preferred Stock issued by the Company shall have the right, voting separately by class or series, to elect directors at an annual or special meeting of stockholders, the election, term of office, filling of vacancies and other features of such directorships shall be governed by the terms of this Certificate of Incorporation and the resolution or resolutions adopted by the Board of Directors providing for the issuance of such class or series, and such directors so elected shall not be divided into classes pursuant to this Article V unless expressly provided by such terms.

C. REMOVAL OF DIRECTORS.

1. Prior to the fifth annual meeting of stockholders to occur after the Effective Date, except as required by applicable law and subject to the rights of any series of Preferred Stock to elect additional directors under specified circumstances, the Board of Directors or any individual director may be removed from office at any time, but only for cause by the affirmative vote of the holders of at least sixty-six and two-thirds percent (66 2/3%) of the voting power of all then-outstanding shares of capital stock of the Company entitled to vote generally at an election of directors.

2. Beginning with the fifth annual meeting of stockholders to occur after the Effective Date, subject to the rights of any series of Preferred Stock to elect additional directors under specified circumstances, the Board of Directors or any individual director may be removed from office at any time, with or without cause, by the affirmative vote of the holders of at least sixty-six and two-thirds percent (66 2/3%) of the voting power of all then-outstanding shares of capital stock of the Company entitled to vote generally at an election of directors.

D. VACANCIES. Subject to any limitations imposed by applicable law and subject to the rights of the holders of any series of Preferred Stock, any vacancies on the Board of Directors resulting from death, resignation, disqualification, removal or other causes and any newly created directorships resulting from any increase in the number of directors, shall, unless the Board of Directors determines by resolution that any such vacancies or newly created directorships shall be filled by the stockholders and except as otherwise provided by applicable law, be filled only by the affirmative vote of a majority of the directors then in office, even though less than a quorum of the Board of Directors, and not by the stockholders. Any director elected in accordance with the preceding sentence shall hold office for the remainder of the full term of the director for which the vacancy was created or occurred and until such director’s successor shall have been elected and qualified.

E. BYLAW AMENDMENTS.

1. The Board of Directors is expressly empowered to adopt, amend or repeal the Bylaws of the Company. Any adoption, amendment or repeal of the Bylaws of the Company by the Board of Directors shall require the approval of a majority of the authorized number of directors. The stockholders shall also have power to adopt, amend or repeal the Bylaws of the Company; provided, however, that, in addition to any vote of the holders of any class or series of stock of the Company required by law or by this Certificate of Incorporation, such action by stockholders shall require the affirmative vote of the holders of at least sixty-six and two-thirds percent (66 2/3%) of the voting power of all of the then-outstanding shares of the capital stock of the Company entitled to vote generally in the election of directors, voting together as a single class.

2. The directors of the Company need not be elected by written ballot unless the Bylaws so provide.

3. No action shall be taken by the stockholders of the Company except at an annual or special meeting of stockholders called in accordance with the Bylaws, and no action shall be taken by the stockholders by written consent or electronic transmission.

4. 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 Company shall be given in the manner provided in the Bylaws of the Company.

5. In the event that a member of the Board of Directors of the Company who is not an employee of the Company, or any partner, member, director, stockholder, employee or agent of such member, other than someone who is an employee of the Company (collectively, the “Covered Persons”), acquires knowledge of any business opportunity matter, potential transaction, interest or other matter, unless such matter, transaction or interest is presented to, or acquired, created or developed by, or otherwise comes into the possession of, a Covered Person expressly and solely in connection with such individual’s service as a member of the Board of Directors of the Company (a “Corporate Opportunity”), then the Company, pursuant to Section 122(17) of the DGCL and to the maximum extent permitted from time to time under Delaware law, (i) renounces any expectancy that such Covered Person offer an opportunity to participate in such Corporate Opportunity to the Company and (ii) to the fullest extent permitted by law, waives any claim that such opportunity constituted a Corporate Opportunity that should have been presented by such Covered Person to the Company or any of its affiliates. No amendment or repeal of this paragraph shall apply to or have any effect on the liability or alleged liability of any officer, director or stockholder of the Company for or with respect to any opportunities of which such officer, director or stockholder becomes aware prior to such amendment or repeal.

ARTICLE VI

No director of the Company shall have any personal liability to the Company or its stockholders for monetary damages for any 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 hereafter may be amended. Any amendment, repeal or modification of this Article VI, or the adoption of any provision of the Certificate of Incorporation of the Company inconsistent with this Article VI, shall not adversely affect any right or protection of a director of the Company with respect to any act or omission occurring prior to such amendment, repeal, modification or adoption. If the DGCL is amended after approval by the stockholders of this Article VI to authorize corporate action further eliminating or limiting the personal liability of directors, then the liability of a director of the Company shall be eliminated or limited to the fullest extent permitted by the DGCL as so amended.

ARTICLE VII

A. The Company shall indemnify its directors and executive officers to the fullest extent authorized or permitted by applicable law, as now or hereafter in effect, and such right to indemnification shall continue as to a person who has ceased to be a director or executive officer of the Company and shall inure to the benefit of his or her heirs, executors and personal and legal representatives; provided, however, that the Company shall not be required to indemnify any director or executive officer in connection with any proceeding (or part thereof) initiated by such person unless (i) such indemnification is expressly required to be made by law, (ii) the proceeding was authorized by the Board of Directors, (iii) such indemnification is provided by the Company, in its sole discretion, pursuant to the powers vested in the corporation under the DGCL or any other applicable law or (iv) such indemnification is required to be made under the Bylaws. The right to indemnification conferred by this Article VII shall include the right to be paid by the Company the expenses incurred in defending or otherwise participating in any proceeding in advance of its final disposition upon receipt by the Company of an undertaking by or on behalf of the director or executive officer receiving advancement to repay the amount advanced if it shall ultimately be determined that such person is not entitled to be indemnified by the Company under this Article VII. The Company may, to the extent authorized from time to time by the Board of Directors, provide rights to indemnification and to the advancement of expenses to other officers, employees and agents of the Company similar to those conferred in this Article VII to directors and executive officers of the Company. The rights to indemnification and to the advancement of expenses conferred in this Article VII shall not be

exclusive of any other right which any person may have or hereafter acquire under this Certificate of Incorporation, the Bylaws, any statute, agreement, vote of stockholders or disinterested directors or otherwise. Any repeal or modification of this Article VII by the stockholders of the Company shall, unless otherwise required by law, be prospective only (except to the extent such amendment or change in law permits the Company to provide broader indemnification rights on a retroactive basis than permitted prior thereto), and shall not adversely affect any rights to indemnification and to the advancement of expenses of a director, executive officer, other officer, employee or agent of the Company (collectively, the “Indemnified Persons”) existing at the time of such repeal or modification 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 modification of such inconsistent provision.

B. The Company hereby acknowledges that certain Indemnified Persons may have rights to indemnification and advancement of expenses (directly or through insurance obtained by any such entity) provided by one or more third parties (collectively, the “Other Indemnitors”), and which may include third parties for whom such Indemnified Person serves as a manager, member, officer, employee or agent. The Company hereby agrees and acknowledges that notwithstanding any such rights that a Indemnified Person may have with respect to any Other Indemnitor(s), (i) the Company is the indemnitor of first resort with respect to all Indemnified Persons in respect of all obligations to indemnify and provide advancement of expenses to Indemnified Persons, (ii) the Company shall be required to indemnify and advance the full amount of expenses incurred by the Indemnified Persons, to the fullest extent required by law, the terms of this Certificate of Incorporation, the Bylaws, any agreement to which the Company is a party, any vote of the stockholders or the Board of Directors, or otherwise, without regard to any rights the Indemnified Persons may have against the Other Indemnitors and (iii) to the fullest extent permitted by law, the Company irrevocably waives, relinquishes and releases the Other Indemnitors from any and all claims for contribution, subrogation or any other recovery of any kind in respect thereof. The Company further agrees that no advancement or payment by the Other Indemnitors with respect to any claim for which the Indemnified Persons have sought indemnification from the Company shall affect the foregoing and the Other Indemnitors shall have a right of contribution and/or be subrogated to the extent of any such advancement or payment to all of the rights of recovery of the Indemnified Persons against the Company. These rights shall be a contract right, and the Other Indemnitors are express third party beneficiaries of the terms of this paragraph. Notwithstanding anything to the contrary herein, the obligations of the Company under this paragraph shall only apply to Indemnified Persons in their capacity as Indemnified Persons.

ARTICLE VIII

A. Unless the Company consents in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware (or, if and only if the Court of Chancery of the State of Delaware lacks subject matter jurisdiction, any state court located within the State of Delaware or, if and only if all such state courts lack subject matter jurisdiction, the federal district court for the District of Delaware) and any appellate court therefrom shall be the sole and exclusive forum for the following claims or causes of action under the Delaware statutory or common law: (i) any derivative claim or cause of action brought on behalf of the Company; (ii) any claim or cause of action for breach of a fiduciary duty owed by any current or former director, officer or other employee of the Company, to the Company or the Company’s stockholders; (iii) any claim or cause of action against the Company or any current or former director, officer or other employee of the Company, arising out of or pursuant to any provision of the DGCL, this Certificate of Incorporation or the Bylaws of the Company (as each may be amended from time to time); (iv) any claim or cause of action seeking to interpret, apply, enforce or determine the validity of this Certificate of Incorporation or the Bylaws of the Company (as each may be amended from time to time, including any right, obligation, or remedy thereunder); (v) any claim or cause of action as to which the DGCL confers jurisdiction on the Court of Chancery of the State of Delaware; and (vi) any claim or cause of action against the Company or any current or former director, officer or other employee of the Company, governed by the internal-affairs doctrine or otherwise related to the Company’s internal affairs, in all cases to the fullest extent permitted by law and subject to the court having personal jurisdiction over the indispensable parties named as defendants. This Section A of Article VIII shall not apply to claims or causes of action brought to enforce a duty or liability created by the Securities Act or the Securities Exchange Act of 1934, as amended, or any other claim for which the federal courts have exclusive jurisdiction.

B. Unless the Company consents in writing to the selection of an alternative forum, to the fullest extent permitted by law, the federal district courts of the United States of America shall be the exclusive forum for the resolution of any complaint asserting a cause of action arising under the Securities Act, including all causes of action asserted against any defendant named in such complaint. For the avoidance of doubt, this provision is intended to benefit and may be enforced by the Company, the Company’s officers and directors, the underwriters to any offering giving rise to such complaint, and any other professional entity whose profession gives authority to a statement made by that person or entity and who has prepared or certified any part of the documents underlying the offering.

C. Any person or entity purchasing or otherwise acquiring any interest in shares of capital stock of the Company shall be deemed to have notice of and to have consented to the provisions of this Article VIII.

ARTICLE IX

A. The Company reserves the right to amend, alter, change or repeal any provision contained in this Certificate of Incorporation, in the manner now or hereafter prescribed by statute, except as provided in paragraph B. of this Article IX, and all rights conferred upon the stockholders herein are granted subject to this reservation.

B. Notwithstanding any other provisions of this Certificate of Incorporation or any provision of applicable law which might otherwise permit a lesser vote or no vote, but in addition to any affirmative vote of the holders of any particular class or series of the capital stock of the Company required by law or by this Certificate of Incorporation or any certificate of designation filed with respect to a series of Preferred Stock, the affirmative vote of the holders of at least sixty-six and two-thirds percent (66 2/3%) of the voting power of all of the then outstanding shares of capital stock of the Company entitled to vote generally in the election of directors, voting together as a single class, shall be required to alter, amend or repeal Articles V, VI, VII, VIII and IX.

ARTICLE X

The name and mailing address of the incorporator are as follows:

* * * *

IN WITNESS WHEREOF, this Certificate of Incorporation has been executed this 24th day of June, 2021.

[Signature page to Certificate of Incorporation of Origin Materials, Inc.]