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* BHP BILLITON LTD (Last) (First) (Middle) 180 LONSDALE STREET MELBOURNE (Street) VICTORIA 3000 C3 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol PETROHAWK ENERGY CORP [ HK ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 08/25/2011
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X 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 Stock, par value 0.001 per share(1)	08/25/2011		P		43,738,426(3)	A	$38.75	100(4)	I	See Footnote(2)

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

1. Name and Address of Reporting Person* BHP BILLITON LTD (Last) (First) (Middle) 180 LONSDALE STREET MELBOURNE (Street) VICTORIA 3000 C3 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* BHP Billiton Petroleum International Pty. Ltd. (Last) (First) (Middle) BHP BILLITON CENTRE 180 LONSDALE STREET MELBOURNE (Street) VICTORIA 3000 C3 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* BHP Billiton Petroleum Holdings LLC (Last) (First) (Middle) 1360 POST OAK BOULEVARD SUITE 150 (Street) HOUSTON TX 77056 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* BHP Billiton Petroleum Holdings (USA) Inc. (Last) (First) (Middle) 1360 POST OAK BOULEVARD SUITE 150 (Street) HOUSTON TX 77056 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* BHP Billiton Petroleum (North America) Inc. (Last) (First) (Middle) 1360 POST OAK BOULEVARD SUITE 150 (Street) HOUSTON TX 77056 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* North America Holdings II Inc. (Last) (First) (Middle) 1360 POST OAK BOULEVARD SUITE 150 (Street) HOUSTON TX 77056 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. This form is a joint filing by BHP Billiton Limited, BHP Billiton Petroleum International Pty. Ltd., a wholly owned subsidiary of BHP Billiton Limited ("PTY"), BHP Billiton Petroleum Holdings LLC, a wholly owned subsidiary of PTY ("LLC"), BHP Billiton Petroleum Holdings (USA) Inc., a subsidiary jointly owned by PTY and LLC ("USA"), BHP Billiton Petroleum (North America) Inc., a wholly owned subsidiary of USA ("Parent") and North America Holdings II Inc., a wholly owned subsidiary of Parent ("Merger Sub").

2. Shares were held by Merger Sub. As Merger Sub is an indirect wholly owned subsidiary of each of BHP Billiton Limited, PTY, LLC and USA and a direct wholly owned subsidiary of Parent, each of BHP Billiton Limited, PTY, LLC, USA and Parent may be deemed to have acquired indirect beneficial ownership of the Shares.

3. Reflects all of the outstanding shares of Petrohawk Energy Corporation ("Petrohawk") not acquired through the tender offer effected pursuant to the Agreement and Plan of Merger, dated as of July 14, 2011, entered into by and among BHP Billiton, Parent, Merger Sub and Petrohawk (the "Merger Agreement"), which may be deemed to have been acquired by BHP Billiton, PTY, LLC, USA and Parent pursuant to the consumation of the Merger (as defined below).

4. On August 25, 2011, Merger Sub was merged with and into Petrohawk, with Petrohawk being the surviving corporation as a direct wholly owned subsidiary of Parent sursuant to a "short-form merger" under Delaware law (the "Merger"). At the effective time of the Merger, all of Petrohawk's previously outstanding stock held by the Reporting Persons were canceled. Prior to the Merger, Parent directly held, and therefore BHP Billiton Limited, PTY, LLC and USA may be deemed to have indirectly held, 100 shares of Purchaser, which represented all of the issued and outstnading capital stock of Purchaser. At the effective time of the Merger, each share of Purchaser was converted into a share of the surivving company's common stock.

	/s/ David Williamson, Head of Group Legal & Chief Compliance Officer, BHP Billiton Limited	08/26/2011
	/s/ David Powell, Director, BHP Billiton Petroleum International Pty. Ltd.	08/26/2011
	/s/ David Powell, Vice President, BHP Billiton Petroleum Holdings LLC	08/26/2011
	/s/ David Powell, Vice President, BHP Billiton Petroleum Holdings (USA) Inc.	08/26/2011
	/s/ David Powell, Vice President, BHP Billiton Petroleum (North America) Inc.	08/26/2011
	/s/ David Powell, Vice President, North America Holdings II Inc.	08/26/2011
	** Signature of Reporting Person	Date
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