Blackstone Inc. — Director's Dealing 2011

May 18, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Kosmos Energy Ltd. (KOS)
CIK: 0001509991
Period of Report: 2011-05-16

Reporting Person: Blackstone Holdings III L.P. (10% Owner)
Reporting Person: BLACKSTONE MANAGEMENT ASSOCIATES CAYMAN IV LP (10% Owner)
Reporting Person: BLACKSTONE FAMILY GP LLC (10% Owner)
Reporting Person: Blackstone Holdings III GP L.P. (10% Owner)
Reporting Person: Blackstone Holdings III GP Management L.L.C. (10% Owner)
Reporting Person: Blackstone Group L.P. (10% Owner)
Reporting Person: Blackstone Group Management L.L.C. (10% Owner)
Reporting Person: SCHWARZMAN STEPHEN A (10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-05-16	Common Shares	J	118316711	—	Acquired	118316711	Indirect
2011-05-16	Common Shares	J	1929515	—	Acquired	1929515	Indirect
2011-05-16	Common Shares	J	3120870	—	Acquired	3120870	Indirect
2011-05-16	Common Shares	J	2591243	—	Acquired	2591243	Indirect
2011-05-16	Common Shares	J	351839	—	Acquired	351839	Indirect

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2011-05-16	Series A Convertible Preferred Units	$	J	12336114	Disposed		Common Shares (67046010)	Indirect
2011-05-16	Series B Convertible Preferred Units	$	J	8281115	Disposed		Common Shares (45478980)	Indirect
2011-05-16	Series C Convertible Preferred Units	$	J	364905	Disposed		Common Shares (1984092)	Indirect
2011-05-16	C1 Units	$	J	1030862	Disposed		Common Share (3807630)	Indirect
2011-05-16	Series A Convertible Preferred Units	$	J	201178	Disposed		Common Shares (1093390)	Indirect
2011-05-16	Series B Convertible Preferred Units	$	J	135049	Disposed		Common Shares (741674)	Indirect
2011-05-16	Series C Convertible Preferred Units	$	J	5951	Disposed		Common Shares (32357)	Indirect
2011-05-16	C1 Units	$	J	16811	Disposed		Common Shares (62094)	Indirect
2011-05-16	Series A Convertible Preferred Units	$	J	339602	Disposed		Common Shares (1845716)	Indirect
2011-05-16	Series B Convertible Preferred Units	$	J	204364	Disposed		Common Shares (1122345)	Indirect
2011-05-16	Series C Convertible Preferred Units	$	J	9628	Disposed		Common Shares (52350)	Indirect
2011-05-16	C1 Units	$	J	27198	Disposed		Common Shares (100460)	Indirect
2011-05-16	Series A Convertible Preferred Units	$	J	281970	Disposed		Common Shares (1532489)	Indirect
2011-05-16	Series B Convertible Preferred Units	$	J	169682	Disposed		Common Shares (931875)	Indirect
2011-05-16	Series C Convertible Preferred Units	$	J	7994	Disposed		Common Shares (43466)	Indirect
2011-05-16	C1 Units	$	J	22583	Disposed		Common Shares (83413)	Indirect
2011-05-16	Series A Convertible Preferred Units	$	J	38286	Disposed		Common Shares (208082)	Indirect
2011-05-16	Series B Convertible Preferred Units	$	J	23040	Disposed		Common Shares (126533)	Indirect
2011-05-16	Series C Convertible Preferred Units	$	J	1085	Disposed		Common Shares (5899)	Indirect
2011-05-16	C1 Units	$	J	3066	Disposed		Common Shares (11325)	Indirect

Footnotes

F1: The common shares, par value $0.01 (the "Common Shares") of Kosmos Energy Ltd. (the "Issuer") were issued in exchange for the outstanding units in Kosmos Energy Holdings ("KEH") listed in Table II pursuant to a corporate reorganization (the "Corporate Reorganization") in connection with the initial public offering of Common Shares, which units were exchangeable pursuant to the Fourth Amended and Restated Operating Agreement of KEH upon the closing of the initial public offering of the Issuer based on the pre-offering equity value of such units.

F2: These Common Shares are held by Blackstone Capital Partners (Cayman) IV L.P. ("BCP Cayman IV").

F3: These Common Shares are held by Blackstone Capital Partners (Cayman) IV-A L.P. ("BCP Cayman IV-A").

F4: These Common Shares are held by Blackstone Family Investment Partnership (Cayman) IV-A L.P. ("BFIP")

F5: These Common Shares are held by Blackstone Family Investment Partnership (Cayman) IV-A SMD L.P. ("BFIP SMD").

F6: These Common Shares are held by Blackstone Participation Partnership (Cayman) IV L.P. ("BPP").

F7: Reflects the number of units of KEH owned by BCP Cayman IV prior to their exchange on May 16, 2011 pursuant to the Corporate Reorganization.

F8: Reflects the number of units of KEH owned by BCP Cayman IV-A prior to their exchange on May 16, 2011 pursuant to the Corporate Reorganization.

F9: Reflects the number of units of KEH owned by BFIP prior to their exchange on May 16, 2011 pursuant to the Corporate Reorganization.

F10: Reflects the number of units of KEH owned by BFIP SMD prior to their exchange on May 16, 2011 pursuant to the Corporate Reorganization.

F11: Reflects the number of units of KEH owned by BPP prior to their exchange on May 16, 2011 pursuant to the Corporate Reorganization.

F12: The general partner of BFIP SMD is Blackstone Family GP L.L.C. which is controlled by Mr. Stephen A. Schwarzman, its founder. The general partner of BCP Cayman IV and BCP Cayman IV-A is Blackstone Management Associates (Cayman) IV L.P. ("BMA"). A general partner of BMA, BFIP, and BPP is BCP IV GP L.L.C ("BCP IV"). Blackstone Holdings III L.P. is the sole member of BCP IV. The general partner of Blackstone Holdings III L.P. is Blackstone Holdings III GP L.P. The general partner of Blackstone Holdings III GP L.P. is Blackstone Holdings III GP Management L.L.C. The sole member of Blackstone Holdings III GP Management L.L.C. is The Blackstone Group L.P. The general partner of The Blackstone Group L.P. is Blackstone Group Management L.L.C. Blackstone Group Management L.L.C. is controlled by Mr. Stephen A. Schwarzman, its founder.

F13: Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons are the beneficial owners of any securities reported herein