| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| Hill John W | Director | C/O COSTAR GROUP, INC., 1201 WILSON BLVD., ARLINGTON | /s/ Gene Boxer, Attorney-in-Fact | 17 Nov 2025 | 0001351689 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | CSGP | Common Stock, par value $0.01 per share | Sale | $154,530 | -2,250 | -11% | $68.68 | 18,231 | 13 Nov 2025 | Direct |