SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person* STADIUM CAPITAL MANAGEMENT LLC (Last) (First) (Middle) 19785 VILLAGE OFFICE COURT, SUITE 101 (Street) BEND OR 97702 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 09/24/2009	3. Issuer Name and Ticker or Trading Symbol Builders FirstSource, Inc. [ BLDR ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director 10% Owner Officer (give title below) X Other (specify below) See Footnote 1.	5. 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 Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Stock, par value $0.01 per share	1,786,442	I(1)	By Client Accounts(2)
Common Stock, par value $0.01 per share	3,580,698	I(1)	By Stadium Relative Value Partners, L.P.(3)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person* STADIUM CAPITAL MANAGEMENT LLC (Last) (First) (Middle) 19785 VILLAGE OFFICE COURT, SUITE 101 (Street) BEND OR 97702 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) See Footnote 1.

1. Name and Address of Reporting Person* KENT BRADLEY R (Last) (First) (Middle) C/O STADIUM CAPITAL MANAGEMENT, LLC 19785 VILLAGE OFFICE COURT, SUITE 101 (Street) BEND OR 97702 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) See Footnote 1.

1. Name and Address of Reporting Person* SEAVER ALEXANDER M (Last) (First) (Middle) C/O STADIUM CAPITAL MANAGEMENT, LLC 19785 VILLAGE OFFICE COURT, SUITE 101 (Street) BEND OR 97702 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) See Footnote 1.

1. Name and Address of Reporting Person* STADIUM RELATIVE VALUE PARTNERS LP (Last) (First) (Middle) C/O STADIUM CAPITAL MANAGEMENT, LLC 19785 VILLAGE OFFICE COURT, SUITE 101 (Street) BEND OR 97702 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) See Footnote 1.

Explanation of Responses:

1. This report is filed jointly by Stadium Capital Management, LLC ("SCM"), Stadium Relative Value Partners, L.P. ("SRV"), Bradley R. Kent and Alexander M. Seaver. SCM is the general partner and investment adviser of SRV. Messrs. Kent and Seaver are managers of SCM. By virtue of these relationships, each of the reporting persons may be deemed to be beneficial owners of more than 10% of the outstanding common stock of Builders FirstSource, Inc. (the "Issuer"). SRV is filing this statement jointly with the other reporting persons, but not as a member of a group and expressly disclaims membership in a group. Each of the reporting persons disclaims beneficial ownership of shares of common stock of the Issuer not directly owned by it/him, except to the extent of its/his pecuniary interest therein.

2. Represents shares beneficially owned by SCM that were acquired for client accounts for which SCM is the investment adviser.

3. Represents shares beneficially owned by SRV.

	By: Stadium Capital Management, LLC, By: /s/ Bradley R. Kent, Manager	09/29/2009
	/s/ Kent, Bradley R.	09/29/2009
	/s/ Seaver, Alexander M.	09/29/2009
	By: Stadium Relative Value Partners, L.P., By: Stadium Capital Managment, LLC, By: /s/ Bradley R. Kent, Manager	09/29/2009
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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