SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* Krieger David Benjamin (Last) (First) (Middle) C/O WARBURG PINCUS LLC 450 LEXINGTON AVENUE (Street) NEW YORK NY 10017 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Kosmos Energy Ltd. [ KOS ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 05/16/2011
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Shares	05/16/2011		J(1)		154,379,137(2)	A	$0(1)	154,379,137	I	See Footnotes(1)(2)(3)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Series A Convertible Preferred Units	$0(1)	05/16/2011		J(1)			16,129,849	(1)	(1)	Common Shares	87,664,716	$0(1)	0	I	See Footnote(4)
Series B Convertible Preferred Units	$0(1)	05/16/2011		J(1)			10,771,752	(1)	(1)	Common Shares	59,157,300	$0(1)	0	I	See Footnote(4)
Series C Convertible Preferred Units	$0(1)	05/16/2011		J(1)			476,134	(1)	(1)	Common Shares	2,588,876	$0(1)	0	I	See Footnote(4)
C1 Units	$0(1)	05/16/2011		J(1)			1,345,081	(1)	(1)	Common Shares	4,968,245	$0(1)	0	I	See Footnote(4)

Explanation of Responses:

1. 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 the corporate reorganization (the "Corporate Reorganization") in connection with the initial public offering of Common Shares of the Issuer, 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.

2. Reflects the aggregate number of Common Shares directly owned by Warburg Pincus Private Equity VIII, L.P., a Delaware limited partnership ("WPPE VIII"), together with two affiliated limited partnerships (together with WPPE VIII, "WP VIII"), and Warburg Pincus International Partners, L.P., a Delaware limited partnership ("WPIP LP"), together with two affiliated limited partnerships (together with WPIP LP, "WPIP").

3. Warburg Pincus Partners, LLC, a New York limited liability company ("WP Partners") and direct subsidiary of Warburg Pincus & Co., a New York general partnership ("WP"), is the sole general partner of WPPE VIII and WPIP LP. WP is the managing member of WP Partners. WP VIII and WPIP are managed by Warburg Pincus LLC, a New York limited liability company ("WP LLC"). Charles R. Kaye and Joseph P. Landy are Managing General Partners of WP and Managing Members and Co-Presidents of WP LLC. Mr. Krieger is a Partner of WP and a Managing Director and Member of WP LLC. The Common Shares of the Issuer which WP VIII and WPIP have acquired are reflected as indirectly beneficially owned by Mr. Krieger because of his affiliation with the Warburg Pincus entities. Mr. Krieger disclaims beneficial ownership with respect to any Common Shares of the Issuer in which he does not have a direct pecuniary interest.

4. Reflects the aggregate number of units of KEH directly owned by WP VIII and WPIP prior to the exchange of such units on May 16, 2011 pursuant to the Corporate Reorganization.

	/s/ David B. Krieger	05/18/2011
	** Signature of Reporting Person	Date
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