Form 4 Filing for Michael Hiller at Builders FirstSource, Inc.

This SEC Form 4 filing details a transaction by Michael Hiller, COO-Designate of Builders FirstSource, Inc. On October 18, 2026, Mr. Hiller acquired 12,808 shares of common stock through restricted stock units granted under the Corporation's 2026 Incentive Plan. These units vest in three equal increments on October 18 of 2027, 2028, and 2029. Each vested unit entitles the holder to one share of common stock. The acquisition was made at a transaction price of $0.00 per share. Following this transaction, Mr. Hiller owns 64,950 shares of common stock. The filing is signed by Alena Brenner, by power of attorney.