Builders FirstSource, Inc. (BLDR) · Insider Trading (Form 4) SEC Filing

=== SEC Form 4 — Statement of Changes in Beneficial Ownership === Document Type: 4 Period of Report: 2026-07-18 10b5-1 Pre-arranged Plan: No --- Issuer --- Name: Builders FirstSource, Inc. (BLDR) CIK: 0001316835 --- Reporting Owner --- Name: O'Brien Matthew Coley CIK: 0001732939 Role: Officer (Chief Human Resources Officer) --- Non-Derivative Transactions --- [Transaction #1] Security: Common Stock, par value $0.01 per share Date: 2026-07-18 | Code: A (Grant or award) Shares: +7,406 | Price: $0.00 Shares Owned After: 7,406 | Ownership: D (Direct) Footnotes: [F1] Reflects the acquisition of restricted stock units pursuant to the Corporation's 2026 Incentive Plan. The restricted stock units vest in 33.3% increments on each of July 18, 2027-2029 and entitle the reporting person to one share of common stock for each restricted stock unit that vests. --- Footnotes (Complete Index) --- F1: Reflects the acquisition of restricted stock units pursuant to the Corporation's 2026 Incentive Plan. The restricted stock units vest in 33.3% increments on each of July 18, 2027-2029 and entitle the reporting person to one share of common stock for each restricted stock unit that vests. --- Signature --- /s/ /s/ Alena Brenner, by power of attorney (2026-07-21)