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* JLL PARTNERS FUND V LP (Last) (First) (Middle) 450 LEXINGTON AVE, 31ST FLOOR (Street) NEW YORK NY 10017 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Builders FirstSource, Inc. [ BLDR ]	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) 01/21/2010
	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 $0.01 per share	01/21/2010		X		12,857,143(1)	A	$3.5	21,809,694.5(2)	I	By Building Products, LLC(3)
Common Stock, par value $0.01 per share	01/21/2010		J		2,534,889.5(4)	A	$3.5	24,344,584(2)	I	By JWP LLC(5)

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
Subscription Rights (right to buy)	$3.5	01/21/2010		X			12,857,143(6)	12/15/2009	01/19/2010	Common Stock, par value $0.01 per share	12,857,143	$0.00	0	I	By Building Products, LLC(3)

1. Name and Address of Reporting Person* JLL PARTNERS FUND V LP (Last) (First) (Middle) 450 LEXINGTON AVE, 31ST FLOOR (Street) NEW YORK NY 10017 (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* JLL Associates V, L.P. (Last) (First) (Middle) 450 LEXINGTON AVE, 31ST FLOOR (Street) NEW YORK NY 10017 (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* JLL Associates G.P. V, L.L.C. (Last) (First) (Middle) 450 LEXINGTON AVE, 31ST FLOOR (Street) NEW YORK NY 10017 (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. These shares of common stock, par value $0.01 per share, of Builders FirstSource, Inc. (the "Company") were purchased by Building Products, LLC ("Building Products") pursuant to that certain Investment Agreement, dated as of October 23, 2009 (as amended, the "Investment Agreement"), by and among JLL Partners Fund V, L.P., Warburg Pincus Private Equity IX, L.P. and the Company, upon exercise of subscription rights issued pro rata to holders of the Company's common stock as of the close of business on December 14, 2009, to purchase shares of the Company's common stock at a subscription price of $3.50 per share (the "Rights Offering") under the basic subscription privilege of the Rights Offering.

2. The reporting persons disclaim beneficial ownership of these securities except to the extent of any pecuniary interest therein, and this report shall not be deemed an admission that any of the reporting persons is the beneficial owner of the securities for purposes of Section 16 or for any other purpose.

3. This report is filed jointly by JLL Partners Fund V, L.P., JLL Associates V, L.P. and JLL Associates G.P. V, L.L.C. JLL Partners Fund V, L.P. indirectly beneficially owns 21,809,694.5 shares of common stock of the Company by virtue of its position as a member of Building Products and pursuant to the Amended and Restated Limited Liability Company Agreement of Building Products. JLL Associates V, L.P. is the general partner of JLL Partners Fund V, L.P. JLL Associates G.P. V, L.L.C. is the general partner of JLL Associates V, L.P.

4. These shares of common stock of the Company were acquired pursuant to the provisions of the Investment Agreement that obligated JLL Partners Fund V, L.P. to cause JWP LLC to exchange $48.909 million in aggregate principal amount of the Second Priority Senior Secured Floating Notes due 2012 of the Company held by JWP LLC. On January 21, 2010, upon the closing of the Company's debt exchange, after the allocation of shares of the Company's common stock in accordance with the proration required in the debt exchange, JWP LLC received, on behalf of JLL Partners Fund V, L.P., 2,534,889.5 shares of the Company's common stock in the debt exchange at an exchange price per share of $3.50 and $40,036,886.16 in cash.

5. JLL Partners Fund V, L.P., indirectly beneficially owns 2,534,889.5 shares of common stock of the Company by virtue of its position as a member of JWP LLC and pursuant to the Amended and Restated Limited Liability Company Agreement of JWP LLC. JLL Associates V, L.P. is the general partner of JLL Partners Fund V, L.P. JLL Associates G.P. V, L.L.C. is the general partner of JLL Associates V, L.P.

6. These subscription rights were exercised by JLL Partners Fund V, L.P. pursuant to the Investment Agreement under its basic subscription privilege in the Rights Offering, as described above in Footnote 1.

Remarks:

	JLL Partners Fund V, L.P. JLL Associates V, L.P. JLL Associates G.P. V, L.L.C. /s/ Paul S. Levy, Managing Member of JLL Associates G.P. V, L.L.C.	01/22/2010
	By JLL Associates G.P. V, L.L.C., its general partner, By Paul S. Levy, Managing Member of JLL Associates G.P. V, L.L.C.	01/22/2010
	Paul S. Levy, Managing Member of JLL Associates G.P. V, L.L.C.	01/22/2010
	** Signature of Reporting Person	Date
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