Custom Truck One Source Officer Equity Transactions - April 2026

This Form 4 filing reports equity transactions by Thomas R. Rich, President - Rentals of Custom Truck One Source, Inc. (CTOS), on April 1, 2026. Rich received 100,000 new restricted stock units (RSUs) that vest in four annual installments beginning April 1, 2027, subject to continued service and potential acceleration based on corporate milestones. He also received 75,000 shares of common stock from the vesting of RSUs (50,000 from a 2024 grant and 25,000 from a 2026 grant). Additionally, 22,538 shares were withheld to satisfy tax obligations from the RSU vesting at a price of $6.62 per share. Following these transactions, Rich's direct ownership stands at 363,635 shares of common stock, plus 100,000 unvested RSUs. The filing demonstrates ongoing equity compensation for key executives and includes tax withholding transactions related to equity awards.