CoStar Group Inc (CSGP) Ownership & Trading Activity
Institutional holders, insider transactions, and congressional trades for CSGP. 13F holdings as of 2026-06-30.
In 13F filings for the quarter ended June 30, 2026, 737 institutions reported holding CSGP, with 407.0 million shares worth $11.5 billion in aggregate.
Top Institutional Holders
| Institution | Shares | Value | Change |
|---|---|---|---|
| Vanguard | 68,808,700 | $1.9B | DECREASED |
| BlackRock | 33,813,969 | $958M | INCREASED |
| Bamco Inc | 21,626,763 | $612M | INCREASED |
| Capital Group | 20,836,749 | $590M | INCREASED |
| State Street | 18,410,876 | $521M | DECREASED |
Recent Insider Trades
| Insider | Type | Shares | Value | Date |
|---|---|---|---|---|
| Robin Jack Rossmann (Chief Financial Officer) | TAX-W | 756 | $24K | 2026-10-15 |
| Cynthia Cammett Cann (Chief Accounting Officer) | SELL | 4,788 | $147K | 2026-08-07 |
| John W Hill (Director) | SELL | 3,500 | $106K | 2026-08-05 |
| Andrew C Florance (Founder and CEO) | BUY | 83,300 | $2M | 2026-08-04 |
| Frederick G. Saint (President, Marketplaces) | TAX-W | 1,436 | $41K | 2026-08-01 |
Recent Congressional Trades
| Member | Type | Amount | Date |
|---|---|---|---|
| Ro Khanna (Democrat) | PURCHASE | $1,001 - $15,000 | 2026-09-25 |
| Ro Khanna (Democrat) | PURCHASE | $1,001 - $15,000 | 2026-09-11 |
| Gilbert Cisneros (Democrat) | PURCHASE | $1,001 - $15,000 | 2026-08-19 |
Full institutional holdings, insider history, and congressional trades for CoStar Group Inc on SentiSense.