Exhibit 3.1

CERTIFICATE OF INCORPORATION
OF
ANTERO RESOURCES FINANCE CORPORATION

        FIRST: The name of the corporation is Antero Resources Finance Corporation (the "Corporation").

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

        THIRD: The nature of the business or purposes to be conducted or promoted by the Corporation is to engage in any lawful act or activity for which corporations may be organized under the Delaware General Corporation Law.

        FOURTH: The total number of shares of capital stock which the corporation shall have authority to issue is one thousand (1,000) shares of common stock at a par value of $0.001 per share (the "Common Stock").

        The designations and the powers, preferences, rights, qualifications, limitations and restrictions of the Common Stock are as follows:

        (a)   Each share of Common Stock of the Corporation shall have identical rights and privileges in every respect. Except as may otherwise be provided in this Certificate of Incorporation or by applicable law, the holders of shares of Common Stock shall be entitled to one vote for each such share upon all questions presented to the stockholders and the Common Stock shall have the exclusive right to vote for the election of directors and for all other purposes.

        (b)   The holders of shares of the Common Stock shall be entitled to receive such dividends (payable in cash, stock or otherwise) as may be declared thereon by the board of directors at any time and from time to time out of any funds of the Corporation legally available therefor.

        (c)   In the event of any voluntary or involuntary liquidation, dissolution or winding-up of the Corporation, the holders of shares of the Common Stock shall be entitled to receive all of the remaining assets of the Corporation available for distribution to its stockholders, ratably in proportion to the number of shares of the Common Stock held by them. A liquidation, dissolution or winding-up of the Corporation, as such terms are used in this Paragraph (c), shall not be deemed to be occasioned by or to include any consolidation or merger of the Corporation with or into any other corporation or corporations or other entity or a sale, lease, exchange or conveyance of all or a part of the assets of the Corporation.

        (d)   Subject to the foregoing provisions of this Certificate of Incorporation, the Corporation may issue shares of its Common Stock from time to time for such consideration (not less than the par value thereof) as may be fixed by the board of directors of the Corporation, which is expressly authorized to fix the same in its absolute and uncontrolled discretion subject to the foregoing conditions. Shares so issued for which the consideration shall have been paid or delivered to the Corporation shall be deemed fully paid stock and shall not be liable to any further call or assessment thereon, and the holders of such shares shall not be liable for any further payments in respect of such shares.

        (e)   The Corporation shall have authority to create and issue rights and options entitling their holders to purchase shares of the Corporation's capital stock of any class or series or other securities of the Corporation, and such rights and options shall be evidenced by instrument(s)

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approved by the board of directors of the Corporation. The board of directors of the Corporation shall be empowered to set the exercise price, duration, times for exercise, and other terms of such options or rights; provided, however, that the consideration to be received for any shares of capital stock subject thereto shall not be less than the par value thereof.

        (f)    The Corporation shall be entitled to treat the person in whose name any share of its stock is registered as the owner thereof for all purposes and shall not be bound to recognize any equitable or other claim to, or interest in, such share on the part of any other person, whether or not the Corporation shall have notice thereof, except as expressly provided by applicable law.

        FIFTH: The name of the incorporator is Alvyn A. Schopp, whose mailing address is c/o Antero Resources LLC, 1625 17th Street, Denver, Colorado 80202.

        SIXTH: The name and mailing address of the initial director, who shall serve until the first annual meeting of stockholders or until his successors are elected and qualified, is as follows:

        The number of directors of the Corporation shall be as specified in, or determined in the manner provided in, the bylaws of the Corporation. Unless and except to the extent that the bylaws of the Corporation so provide, the election of directors need not be by written ballot.

        SEVENTH: In furtherance of, and not in limitation of, the powers conferred by the laws of the State of Delaware, the Board of Directors of the Corporation is expressly authorized to adopt, amend or repeal the bylaws of the Corporation, subject to the power of the stockholders of the Corporation to alter or repeal any bylaw whether adopted by them or otherwise.

        EIGHTH: Whenever a compromise or arrangement is proposed between the Corporation and its creditors or any class of them and/or between the Corporation and its stockholders or any class of them, any court of equitable jurisdiction within the State of Delaware may, on the application in a summary way of the Corporation or of any creditor or stockholder thereof or on the application of any receiver or receivers appointed for the Corporation under the provisions of Section 291 of Title 8 of the Delaware Code or on the application of trustees in dissolution or of any receiver or receivers appointed for the Corporation under the provisions of Section 279 of Title 8 of the Delaware Code order a meeting of the creditors or class of creditors, and/or of the stockholders or class of stockholders of the Corporation, as the case may be, to be summoned in such manner as the said court directs. If a majority in number representing three-fourths in value of the creditors or class of creditors, and/or of the stockholders or class of stockholders of the Corporation, as the case may be, agree to any compromise or arrangement and to any reorganization of the Corporation as a consequence of such compromise or arrangement, the said compromise or arrangement and the said reorganization shall, if sanctioned by the court to which the said application has been made, be binding on all the creditors or class of creditors, and/or on all the stockholders or class of stockholders, of the Corporation, as the case may be, and also on the Corporation.

        NINTH: No director of the Corporation shall be liable to the Corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except for liability (i) for any breach of the director's duty of loyalty to the Corporation or its stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) under Section 174 of the Delaware General Corporation Law, or (iv) for any transaction from which the director derived an improper personal benefit. In addition to the circumstances in which a director of the Corporation is not personally liable as set forth in the preceding sentence, a director of the

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Corporation shall not be liable to the fullest extent permitted by any amendment to the Delaware General Corporation Law hereafter enacted that further limits the liability of a director.

        TENTH: The Corporation shall indemnify any person who was, is or is threatened to be made a party to a proceeding (as hereinafter defined) by reason of the fact that he or she (i) is or was a director or officer of the Corporation or (ii) while a director or officer of the Corporation, is or was serving at the request of the Corporation as a director, officer, partner, venturer, proprietor, trustee, employee, agent or similar functionary of another foreign or domestic corporation, partnership, joint venture, sole proprietorship, trust, employee benefit plan or other enterprise, to the fullest extent permitted under the Delaware General Corporation Law, as the same exists or may hereafter be amended. Such right shall be a contract right and as such shall inure to the benefit of any director or officer who is elected and accepts the position of director or officer of the Corporation or elects to continue to serve as a director or officer of the Corporation while this Article Tenth is in effect. Any repeal or amendment of this Article Tenth shall be prospective only and shall not limit the rights of any such director or officer or the obligations of the Corporation with respect to any claim arising from or related to the services of such director or officer in any of the foregoing capacities prior to any such repeal or amendment to this Article Tenth. Such right shall include the right to be paid by the Corporation expenses (including without limitation attorneys' fees) actually and reasonably incurred by him in defending any such proceeding in advance of its final disposition to the maximum extent permitted under the Delaware General Corporation Law, as the same exists or may hereafter be amended. If a claim for indemnification or advancement of expenses hereunder is not paid in full by the Corporation within sixty (60) days after a written claim has been received by the Corporation, the claimant may at any time thereafter bring suit against the Corporation to recover the unpaid amount of the claim, and if successful in whole or in part, the claimant shall also be entitled to be paid the expenses of prosecuting such claim. It shall be a defense to any such action that such indemnification or advancement of costs of defense is not permitted under the Delaware General Corporation Law, but the burden of proving such defense shall be on the Corporation. Neither the failure of the Corporation (including its Board of Directors or any committee thereof, independent legal counsel or stockholders) to have made its determination prior to the commencement of such action that indemnification of, or advancement of costs of defense to, the claimant is permissible in the circumstances nor any actual determination by the Corporation (including its Board or any committee thereof, independent legal counsel or stockholders) that such indemnification or advancement is not permissible shall be a defense to the action or create a presumption that such indemnification or advance is not permissible. In the event of the death of any person having a right of indemnification under the foregoing provisions, such right shall inure to the benefit of his or her heirs, executors, administrators and personal representatives. The rights conferred above shall not be exclusive of any other right which any person may have or hereafter acquire under any statute, bylaw, resolution of stockholders or directors, agreement or otherwise.

        The Corporation may also indemnify any employee or agent of the corporation to the fullest extent permitted by law.

        As used herein, the term "proceeding" means any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative, arbitrative or investigative (other than an action by or in the right of the Corporation), any appeal in such an action, suit or proceeding, any inquiry or investigation that could lead to such an action, suit or proceeding.

        ELEVENTH: No contract or transaction between the Corporation and one or more of its directors, officers or stockholders or between the Corporation and any person (as used herein, "person" means other corporation, partnership, association, firm, trust, joint venture, political subdivision or instrumentality) or other organization in which one or more of its directors, officers or stockholders are directors, officers or stockholders, 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

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the meeting of the board or committee which authorizes the contract or transaction, or solely because his, her or their votes are counted for such purpose, if: (i) the material facts as to his or her 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 of directors 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 (ii) the material facts as to his or her 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 (iii) 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. 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.

        TWELFTH: The Corporation shall have the right, subject to any express provisions or restrictions contained in this certificate of incorporation or bylaws of the Corporation, from time to time, to amend this certificate of incorporation or any provision hereof in any manner now or hereafter provided by law, and all rights and powers of any kind conferred upon a director or stockholder of the Corporation by this certificate of incorporation or any amendment hereof are subject to such right of the Corporation.

[Remainder of Page Intentionally Left Blank]

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        I, the undersigned, being the incorporator herein before named, for the purpose of forming a corporation pursuant to the Delaware General Corporation Law, do make this certificate, hereby declaring that this is my act and deed and that the facts herein stated are true, and accordingly have hereunto set my hand this 23rd day of October, 2009.

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