X0306 4 2018-02-09 0 0001690769 Alta Mesa Resources, Inc. /DE AMR 0001700806 Silver Run Sponsor II, LLC C/O RIVERSTONE HOLDINGS LLC 712 FIFTH AVENUE, 36TH FLOOR NEW YORK NY 10019 1 0 1 0 0001701270 Riverstone VI SR II Holdings, L.P. C/O RIVERSTONE HOLDINGS LLC 712 FIFTH AVENUE, 36TH FLOOR NEW YORK NY 10019 0 0 1 0 0001701276 Riverstone Energy VI Holdings GP, LLC C/O RIVERSTONE HOLDINGS LLC 712 FIFTH AVENUE, 36TH FLOOR NEW YORK NY 10019 0 0 1 0 0001686391 Riverstone Energy Partners VI, L.P. C/O RIVERSTONE HOLDINGS LLC 712 FIFTH AVENUE, 36TH FLOOR NEW YORK NY 10019 0 0 1 0 0001686387 Riverstone Energy GP VI, LLC C/O RIVERSTONE HOLDINGS LLC 712 FIFTH AVENUE, 36TH FLOOR NEW YORK NY 10019 0 0 1 0 0001686355 Riverstone Energy GP VI Corp. C/O RIVERSTONE HOLDINGS LLC 712 FIFTH AVENUE, 36TH FLOOR NEW YORK NY 10019 0 0 1 0 0001247497 RIVERSTONE HOLDINGS LLC C/O RIVERSTONE HOLDINGS LLC 712 FIFTH AVENUE, 36TH FLOOR NEW YORK NY 10019 0 0 1 0 0001232151 LAPEYRE PIERRE F JR C/O RIVERSTONE HOLDINGS LLC 712 FIFTH AVENUE, 36TH FLOOR NEW YORK NY 10019 1 0 1 0 0001222726 LEUSCHEN DAVID M C/O RIVERSTONE HOLDINGS LLC 712 FIFTH AVENUE, 36TH FLOOR NEW YORK NY 10019 1 0 1 0 Class A Common Stock 2018-02-09 4 A 0 40000000 10 A 40000000 I See footnotes Class A Common Stock 2018-02-09 4 C 0 25776000 A 65776000 I See footnotes Class C Common Stock 2018-02-09 4 A 0 20000000 A 20000000 I See footnotes Warrants (right to buy) 11.50 2018-02-09 4 A 0 28466666 1.50 A 2018-03-11 2023-02-09 Class A Common Stock 28466666 28466666 I See footnotes Class B Common Stock 2018-02-09 4 C 0 25776000 0 D Class A Common Stock 25776000 0 I See footnotes Common Units 2018-02-09 4 A 0 20000000 A Class A Common Stock 20000000 20000000 I See footnotes Following the transactions reported herein, includes 16,548,894 shares held of record by Silver Run Sponsor II, LLC ("Sponsor"), 18,522,000 shares held of record by Riverstone VI SR II Holdings, L.P. ("SR II Holdings"), 25,857,148 shares held by Riverstone AMR Partners, L.P. ("AMR Partners"), 1,720,243 shares held of record by Riverstone AMR Partners-U, LLC ("AMR Partners-U") and 3,127,715 shares held of record by Riverstone AMR Partners-T, L.P. Prior to the transactions reported herein, the Class B Common Stock was held of record by Sponsor. In connection with the closing of the initial business combination of the Issuer (the "Initial Business Combination"), each share of Class B Common Stock automatically converted into Class A Common Stock of the Issuer on a 1-to-1 basis. Held of record by Riverstone VI Alta Mesa Holdings, L.P. ("Riverstone Contributor" and, together with the Sponsor, SR II Holdings, AMR Partners, AMR Partners-U and AMR Partners-T, the "Riverstone Funds"). In connection with the closing of the Issuer's Initial Business Combination, the Issuer issued Riverstone Contributor 20,000,000 shares of Class C Common Stock and caused SRII Opco, LP to issue an equal number of its common units (the "SRII Opco Common Units") to the Riverstone Contributor in exchange for certain assets of Riverstone Contributor. The SRII Opco Common Units may, at the option of Riverstone Contributor, be redeemed for shares of Class A Common Stock on a one-to-one basis at any time after 180 days after the closing of the Initial Business Combination and have no expiration date. Upon redemption, an equal number of shares of Class C Common Stock will be cancelled. Includes 9,716,012 warrants held of record by Sponsor, 13,333,333 warrants held of record by SR II Holdings, 4,561,992 warrants held by AMR Partners, 303,504 warrants held of record by AMR Partners-U and 551,825 warrants held of record by AMR Partners-T. Of these, 15,133,333 warrants were purchased simultaneous with the closing of the Issuer's initial public offering on March 29, 2017, and 13,333,333 warrants were issued pursuant to a forward purchase agreement dated as of March 17, 2017. The warrants became exercisable after the completion of the Initial Business Combination, which occurred on February 9, 2018. David M. Leuschen and Pierre F. Lapeyre, Jr. are the members of Riverstone Management Group, L.L.C. ("Riverstone Management"), which is the general partner of Riverstone/Gower Mgmt Co Holdings, L.P. ("Riverstone/Gower"), which is the sole member of Riverstone Holdings LLC ("Holdings"), which is the sole shareholder of Riverstone Energy GP VI Corp, which is the managing member of Riverstone Energy GP VI, LLC ("Riverstone Energy GP") which is the general partner of Riverstone Energy Partners VI, L.P., which is the general partner of AMR Partners, the manager of AMR Partners-U and the managing member of Riverstone Energy VI Holdings GP, LLC, which is the general partner of each of the Riverstone Contributor and SR II Holdings, which is the sole and managing member of Sponsor. Riverstone Energy GP is also the sole member of Riverstone Energy Partners VI (Non-U.S.), LLC, which is the general partner of AMR Partners-T, L.P. Riverstone Energy GP is managed by a managing committee consisting of Pierre F. Lapeyre, Jr., David M. Leuschen, E. Bartow Jones, N. John Lancaster, Baran Tekkora and Robert M. Tichio. As such, each of Riverstone Energy GP, Riverstone Energy GP VI Corp, Holdings, Riverstone/Gower, Riverstone Management, Mr. Leuschen and Mr. Lapeyre may be deemed to have or share beneficial ownership of the securities held directly by the Riverstone Funds. Each such entity or person disclaims any such beneficial ownership of such securities except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that the reporting person is the beneficial owner of the securities for purposes of Section 16 or for any other purpose. Silver Run Sponsor II, LLC By: /s/ Thomas J. Walker, Managing Director 2018-02-13 Riverstone VI SR II Holdings, L.P. By: Riverstone Energy VI Holdings GP, LLC , its general partner By: /s/ Thomas J. Walker, Managing Director 2018-02-13 Riverstone Energy VI Holdings GP, LLC By: /s/ Thomas J. Walker, Managing Director 2018-02-13 Riverstone Energy Partners VI, L.P. By: Riverstone Energy GP VI, LLC, its general partner By: /s/ Thomas J. Walker, Managing Director 2018-02-13 Riverstone Energy GP VI, LLC By: /s/ Thomas J. Walker, Managing Director 2018-02-13 Riverstone Energy GP VI Corp By: /s/ Thomas J. Walker, Vice President 2018-02-13 Riverstone Holdings LLC By: /s/ Thomas J. Walker, Authorized Person 2018-02-13 David M. Lesuchen By: /s/ Thomas J. Walker, Attorney-in-Fact 2018-02-13 Pierre F. Lapeyre, Jr. By: /s/ Thomas J. Walker, Attorney-in-Fact 2018-02-13