Form 4 Filing for COSTAR GROUP, INC.

Cynthia Cammett, Chief Accounting Officer of COSTAR GROUP, INC. (CSGP), reported a transaction on July 31, 2026. She acquired 26,078 Restricted Stock Units (RSUs) with a transaction value of $0.00. These RSUs are convertible to common stock. On August 1, 2026, she disposed of 1,077 shares of common stock at a price of $28.76 per share, resulting in 23,610 shares remaining. The RSUs vest in four equal installments starting August 1, 2027, through August 1, 2030. This filing is a Form 4.