Form 4 Filing for David E. Rush

This Form 4 filing reports a transaction by David E. Rush, a director at Builders FirstSource, Inc. On March 15, 2026, Mr. Rush disposed of 2,332 shares of common stock, valued at $88.09 per share, through a transaction coded as "F". This transaction resulted in 127,284 shares of common stock remaining in his ownership. The filing indicates that the shares were withheld to cover tax obligations related to the vesting of previously granted restricted stock units, as noted in footnote F1. The transaction was electronically signed on March 17, 2025, by an attorney-in-fact.