Exhibit 3.1

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

VNOM SUB, INC.

ARTICLE I

The name of the corporation is VNOM Sub, Inc. (the “Corporation”).

ARTICLE II

The street address of the registered office of the Corporation in the State of Delaware is 251 Little Falls Drive, City of Wilmington, County of New Castle, Delaware 19808 and the name of the Corporation’s registered agent at such address is Corporation Service Company.

ARTICLE III

The purpose of the Corporation shall be to engage in any lawful act or activity for which corporations may be organized and incorporated under the General Corporation Law of the State of Delaware (the “DGCL”).

ARTICLE IV

Section 1. The Corporation shall be authorized to issue 100 shares of capital stock, all of which 100 shares shall be shares of common stock, par value $0.01 per share (the “Common Stock”). The Corporation may, but shall not be required to, issue fractions of a share.

Section 2. Except as otherwise provided by law, the Common Stock shall have the exclusive right to vote for the election of directors and for all other purposes. Each share of the Common Stock shall have one vote and the Common Stock shall vote together as a single class.

ARTICLE V

Any one or more directors may be removed, with or without cause, by the vote or written consent of the holders of a majority of the issued and outstanding shares of capital stock of the Corporation entitled to be voted in the election of directors.

ARTICLE VI

In furtherance and not in limitation of those powers conferred by law, the board of directors of the Corporation (the “Board”) is expressly authorized and empowered to make, alter and repeal the by-laws of the Corporation (the “By-Laws”).

ARTICLE VII

Meetings of the stockholders shall be held at such place, within or without the State of Delaware as may be designated by, or in the manner provided in, the By-Laws or, if not so designated, at the registered office of the Corporation in the State of Delaware. Elections of directors need not be by written ballot unless and to the extent that the By-Laws so provide.

ARTICLE VIII

The Corporation reserves the right at any time, and from time to time, to amend, alter, change or repeal any provision contained in this Certificate of Incorporation, and any other provisions authorized by the laws of the State of Delaware at the time in force may be added or inserted, in the manner now or hereinafter prescribed by law, and all rights, preferences and privileges of whatsoever nature conferred upon stockholders, directors or any other persons whomsoever by and pursuant to this Certificate of Incorporation in its present form or as hereafter amended are granted subject to the right reserved in this Article.

ARTICLE IX

No director or officer shall have any personal liability to the Corporation or to its stockholders for monetary damages for breach of fiduciary duty as a director or officer, as applicable, except to the extent such exemption from liability, or limitation thereof, is not permitted under the DGCL. If the DGCL is amended to authorize corporate action further eliminating or limiting the personal liability of directors or officers, as applicable, then the liability of a director or officer, as applicable, of the Corporation shall be eliminated or limited to the fullest extent permitted by the DGCL as so amended. Any repeal or modification of this Article IX shall not adversely affect any right or protection of a director or officer, as applicable, of the Corporation with respect to any act or omission occurring prior to the repeal or modification of this provision.

To the fullest extent permitted by applicable law, the Corporation is authorized to provide indemnification of (and advancement of expenses to) current and former directors, officers and agents of the Corporation (and any other persons to which applicable law permits the Corporation to provide indemnification and advancement of expenses) through provisions of the By-Laws, agreements with such persons, vote of stockholders or disinterested directors, or otherwise. Any repeal or modification of this provision shall not adversely affect any right or protection hereunder of any person in respect of any act or omission occurring prior to the time of such repeal or modification.

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VNOM Sub, Inc. 8-K