COSTAR GROUP INC
819 institutions still hold COSTAR GROUP INC as of Q1 2026. Tracked across SEC 13F-HR filings, with insider and 13D/G activity surfaced alongside.
CoStar Group's (CSGP) two largest owners moved in opposite directions in Q2 2026, at the top of a holder base spanning $141.8 million in institutional value across 61 filers. Douglas Lane & Associates, the top holder at $33.1 million (23.4% of total institutional value), increased its stake 45.4% — a genuine $10.3 million addition, the largest true buy in the entire holder base. Riverbridge Partners, the second-largest holder at $30.9 million, cut its position 11.1% (-$3.8 million), the largest real sale this quarter. PensionDanmark was the most aggressive seller by percentage, slashing its stake 71.4% (-$2.8 million). Elsewhere, buying was broad: Y-Intercept (Hong Kong) Ltd added 34.9% ($3.1 million), Swedbank AB nearly doubled its position (+83.9%, $2.3 million), and Wealth Enhancement Advisory Services more than tripled its stake (+219.2%, $2.2 million). United Asset Strategies opened the largest new position this quarter at $13.8 million, instantly the third-largest holder in the stock.
Top holders
Sorted by position value. Source: SEC EDGAR 13F-HR filings.