FANG Diamondback Energy Inc

Item 1(b). Address of Issuer’s Principal Executive Offices: 500 West Texas Avenue, Suite 1200, Midland, Texas 79701.

Item 2(a). Name of Person Filing : This statement is jointly filed by Brigham Resources Upstream Holdings, LP, a Delaware limited partnership (“Brigham Upstream”), Brigham Resources, LLC, a Delaware limited liability company (“Brigham”), Warburg Pincus & Company US, LLC, a New York limited liability company (“Warburg Pincus”) and PBRA, LLC, a Delaware limited liability company (“Pine Brook”), Yorktown IX Associates LLC, a Delaware limited liability company, Yorktown X Associates LLC, a Delaware limited liability company, Yorktown XI Associates LLC, a Delaware limited liability company, and YT Brigham Associates LLC, a Delaware limited liability company (collectively, “Yorktown”), (collectively, the “Reporting Persons”).

Item 2(b). Address of Principal Business Office or, if None, Residence : The principal business office address of Brigham Upstream and Brigham is 5914 W. Courtyard Drive, Suite 200, Austin, Texas 78730. The principal business office address of Warburg Pincus is c/o Warburg Pincus LLC, 450 Lexington Avenue, New York, NY 10017. The principal business address of Pine Brook is One Grand Central Place, 60 East 42nd Street, 50th Floor, New York, NY. The principal business office address of each member of Yorktown is 410 Park Avenue, 19 ^th Floor, New York, NY 10022.

Item 2(c). Citizenship : Brigham Upstream, Brigham, Pine Brook and all of the members of Yorktown are organized under the laws of the State of Delaware. Warburg Pincus is organized under the laws of the State of New York.

Item 2(d). Title of Class  of Securities : Common Stock.

Item 2(e). CUSIP Number : 25278X109

Item 3. If this statement is filed pursuant to § 240.13d-1(b), or § 240.13d-2(b) or (c), check whether the person filing is a :

(a) ☐ Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).

(b) ☐ Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).

(c) ☐ Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).

(d) ☐ Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8).

(e) ☐ An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);

(f) ☐ An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);

(g) ☐ A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);

(h) ☐ A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

(i) ☐ A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);

(j) ☐ A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J).

(k) ☐ Group, in accordance with § 240.13d-1(b)(1)(ii)(K).

If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:

Item 4. Ownership .

The information regarding ownership set forth in Items 5-9 and 11 of each cover page is hereby incorporated herein by reference.

Warburg Pincus may be deemed to be the ultimate controlling entity of certain Warburg Pincus affiliated entities, including the following, which are members of Brigham: (1) Warburg Pincus Private Equity (E&P) XI-A (Brigham), LLC, a Delaware limited liability company (“WPPE E&P XI-A Brigham”), (2) Warburg Pincus XI (E&P) Partners-A (Brigham), LLC, a Delaware limited liability company (“WP XI E&P Partners-A Brigham”), (3) Warburg Pincus Private Equity (E&P) XI (Brigham), LLC, a Delaware limited liability company (“WPPE E&P XI Brigham”), (4) Warburg Pincus XI (E&P) Partners-B (Brigham), LLC, a Delaware limited liability company (“WP XI E&P Partners-B Brigham”), (5) WP Brigham Holdings, L.P., a Delaware limited partnership (“WP Brigham Holdings”), (6) Warburg Pincus Energy (E&P)-A (Brigham), LLC, a Delaware limited liability company (“WPE E&P-A Brigham”), (7) Warburg Pincus Energy (E&P) Partners-A (Brigham), LLC, a Delaware limited liability company (“WPE E&P Partners-A Brigham”), (8) Warburg Pincus Energy (E&P) (Brigham), LLC, a Delaware limited liability company (“WPE E&P Brigham”), (9) Warburg Pincus Energy (E&P) Partners-B (Brigham), LLC, a Delaware limited liability company (“WPE E&P Partners-B Brigham”), (10) WP Energy Partners (E&P) (Brigham), LLC, a Delaware limited liability company (“WPE Partners E&P Brigham”), (11) WP Energy Brigham Holdings, L.P., a Delaware limited partnership (“WPE Brigham Holdings”), and (12) WP Energy Partners Brigham Holdings, L.P., a Delaware limited partnership (“WPE Partners Brigham Holdings”, and together with the entities in (1) through (11), the “WP Group”).

Warburg Pincus Private Equity (E&P) XI-A, L.P., a Delaware limited partnership (“WPPE E&P XI-A”), is the sole member of WPPE E&P XI-A Brigham. Warburg Pincus XI (E&P) Partners – A, L.P., a Delaware limited partnership (“WP XI E&P Partners-A”), is the sole member of WP XI E&P Partners-A Brigham. Warburg Pincus Energy (E&P)-A, L.P., a Delaware limited partnership (“WPE E&P-A”), is the sole and managing member of WPE E&P-A Brigham. Warburg Pincus Energy (E&P) Partners-A, L.P., a Delaware limited partnership (“WPE E&P Partners-A”), is the sole and managing member of WPE E&P Partners-A Brigham. Effective as of March 5, 2017, Brigham Parent Holdings, L.P., a Delaware limited partnership (“Brigham Parent Holdings”), is the sole and managing member of WPPE E&P XI Brigham, WP XI E&P Partners-B Brigham, WPE E&P Brigham, WPE E&P Partners-B Brigham, and WPE Partners E&P Brigham.

Warburg Pincus (E&P) XI, L.P., a Delaware limited partnership (“WP XI E&P GP”), is the general partner of each of WP Brigham Holdings, WPPE E&P XI-A, WP XI E&P Partners-A, and Brigham Parent Holdings. Warburg Pincus (E&P) XI LLC, a Delaware limited liability company (“WP XI E&P LLC”), is the general partner of WP XI E&P GP. Warburg Pincus Partners (E&P) XI LLC, a Delaware limited liability company (“WP Partners E&P XI LLC”), is the sole member of WP XI E&P LLC. Warburg Pincus Partners II (US), L.P., a Delaware limited partnership (“WPP II US”), is the managing member of WP Partners E&P XI LLC. Warburg Pincus is the general partner of WPP II US.

Warburg Pincus (E&P) Energy GP, L.P., a Delaware limited partnership (“WPE E&P GP”), is the general partner of each of WPE Brigham Holdings, WPE Partners Brigham Holdings, WPE E&P-A, and WPE E&P Partners-A. Warburg Pincus (E&P) Energy LLC, a Delaware limited liability company (“WPE E&P LLC”, and together with WP XI E&P GP, WP XI E&P LLC, WP Partners E&P XI LLC, WPE E&P GP, WPP II US, and Warburg Pincus, the “Warburg Pincus GP Entities”), is the general partner of WPE E&P GP. WPP II US is the managing member of WPE E&P LLC. As noted above, Warburg Pincus is the general partner of WPP II US. Warburg Pincus LLC, a New York limited liability company (“WP LLC”), is the manager of each of WP Brigham Holdings, WPPE E&P XI-A, WP XI E&P Partners-A, WPE Brigham Holdings, WPE Partners Brigham Holdings, WPE E&P-A, and WPE E&P Partners-A.

For the purposes of this filing, the WP Group, WPPE E&P XI-A, WP XI E&P Partners-A, WPE E&P-A, WPE E&P Partners-A, Brigham Parent Holdings, the Warburg Pincus GP Entities, and WP LLC shall, collectively, be known as the “Warburg Pincus Entities.” The Warburg Pincus Entities have an approximately 36% interest in Brigham.

Charles R. Kaye and Joseph P. Landy are the Managing Members of Warburg Pincus and the Managing Members and Co-Chief Executive Officers of WP LLC and, as such, may be deemed to control each of the Warburg Pincus Entities. Messrs. Kaye and Landy disclaim beneficial ownership of all shares held by the Warburg Pincus Entities.

As further described above in footnote (1) on the reporting page for Warburg Pincus, the WP Group may be deemed to have the power to vote or direct the vote or to dispose or direct the disposition of the shares owned by Brigham and Brigham Upstream. Each of the Warburg Pincus Entities (including each of the members of the WP Group), and Messrs. Kaye and Landy expressly disclaims beneficial ownership of the securities owned by Brigham and Brigham Upstream in excess of their respective pecuniary interest therein.

PBRA, a Delaware limited liability company, may be deemed to be the ultimate controlling entity of certain PBRA affiliated entities, including the following, which are members of Brigham: (1) Pine Brook BXP Intermediate, L.P., a Delaware limited partnership (“PB-BXP”) and (2) Pine Brook BXP II Intermediate, L.P., a Delaware limited partnership (“PB-BXP II”), and together with PB-BXP, the “Pine Brook Group”).

Howard H. Newman is the Managing Member of PBRA and, as such, may be deemed to control the Pine Brook Group. Mr. Newman disclaims beneficial ownership of all shares held by the Pine Brook Group.

As further described above in footnote (1) on the reporting page for PBRA, the Pine Brook Group may be deemed to have the power to vote or direct the vote or to dispose or direct the disposition of the shares owned by Brigham and Brigham Upstream. Each of the Pine Brook Group entities and Mr. Newman expressly disclaims beneficial ownership of the securities owned by Brigham and Brigham Upstream in excess of their respective pecuniary interest therein.

Item 5. Ownership of Five Percent or Less of a Class .

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than 5 percent of the class of securities, check the following [ ].

Item 6. Ownership of More Than Five Percent on Behalf of Another Person .

Not applicable

Item 7. Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person .

Not applicable

Item 8. Identification and Classification of Members of the Group .

Not applicable

Item 9. Notice of Dissolution of Group .

Not applicable

Item 10. Certifications .

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under §240.14a-11.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

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