X0306 4 2013-02-26 0 0001316835 Builders FirstSource, Inc. BLDR 0001389137 Tolly Morris E 2001 BRYAN ST., SUITE 1600 DALLAS TX 75201 0 1 0 0 Sr Vice President-Operations Common Stock, par value $0.01 per share 2013-02-26 4 M 0 10800 3.15 A 110267 D Common Stock, par value $0.01 per share 2013-02-26 4 M 0 19200 3.15 A 129467 D Common Stock, par value $0.01 per share 2013-02-26 4 S 0 30000 5.64 D 99467 D Employee Stock Option (right to buy) 3.15 2013-02-26 4 M 0 10800 0.00 D 2023-01-01 Common Stock 10800 0 D Employee Stock Option (right to buy) 3.15 2013-02-26 4 M 0 19200 0.00 D 2024-02-27 Common Stock 19200 43300 D This transaction was executed in multiple trades at prices ranging from $5.58 to $5.73 per share. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide full information regarding the number of shares and prices at which the transactions were effected upon request by the SEC staff, the issuer, or a security holder of the issuer. Award issued under the Company's 1998 Stock Incentive Plan, as amended and restated March 1, 2004. The option was originally granted on January 1, 2003 and vested in one-fifth increments based on the attainment of financial performance targets on each of January 1, 2004-2008. The option was originally granted on March 1, 2004 and vested based on the attainment of financial performance targets as follows: (i) one-sixth on on each of December 31, 2004-2005 and (ii) two-thirds on December 31, 2006. /s/ Morris E. Tolly 2013-02-28