CoStar Group Ownership & Insider Activity

CoStar Group (CSGP) institutional and insider ownership, recent insider transactions and ownership breakdown.

Insiders own 1.6% of shares outstanding. Institutional investors hold 75.1%.

Shares Outstanding

402.337M

Shares Float

399.398M

Insider Shares Owned

6.365M

Insider % Owned

1.6%

Institutional Shares Held

304.125M

Institutional % Held

75.1%

Ownership Breakdown

Net Insider Activity by Month

CoStar Group Insider Transactions (Last 6 Months)

Date	Insider	Title	Type	Shares	Price	Value
Aug 7, 2026	Cammett Cynthia Cann	CHIEF ACCOUNTING OFFICER	SELL	4.788K	$30.78	$147K
Aug 5, 2026	John Hill	DIRECTOR	SELL	3.500K	$30.21	$106K
Aug 4, 2026	ANDREW FLORANCE	FOUNDER AND CEO	BUY	83.300K	$29.89	$2.5M

Date	Member	Party	Chamber	Action	Amount
Aug 19, 2026	Gilbert Ray Cisneros	D	House	Purchase	$1,001 - $15,000
Apr 14, 2026	Gilbert Ray Cisneros	D	House	Sale (Partial)	$1,001 - $15,000
Mar 13, 2026	Gilbert Ray Cisneros	D	House	Purchase	$1,001 - $15,000
Jan 28, 2026	Gilbert Ray Cisneros	D	House	Purchase	$1,001 - $15,000
Dec 10, 2025	Gilbert Ray Cisneros	D	House	Purchase	$1,001 - $15,000
Oct 15, 2025	Gilbert Ray Cisneros	D	House	Purchase	$1,001 - $15,000
Sep 30, 2025	Gilbert Ray Cisneros	D	House	Purchase	$1,001 - $15,000
Sep 25, 2025	Lisa McClain	R	House	Sale	$1,001 - $15,000
Sep 22, 2025	Gilbert Ray Cisneros	D	House	Purchase	$1,001 - $15,000
Aug 13, 2025	Lisa McClain	R	House	Purchase	$1,001 - $15,000
Jul 31, 2025	Gilbert Ray Cisneros	D	House	Purchase	$1,001 - $15,000
Jul 9, 2025	Gilbert Ray Cisneros	D	House	Purchase	$1,001 - $15,000
Jun 30, 2025	Gilbert Ray Cisneros	D	House	Purchase	$1,001 - $15,000
Jun 27, 2025	Gilbert Ray Cisneros	D	House	Purchase	$15,001 - $50,000
Jun 25, 2025	Gilbert Ray Cisneros	D	House	Purchase	$1,001 - $15,000
May 15, 2025	Robert Bresnahan	R	House	Sale	$1,001 - $15,000
May 12, 2025	Jefferson Shreve	R	House	Sale	$15,001 - $50,000
Feb 24, 2025	Jefferson Shreve	R	House	Purchase	$15,001 - $50,000
Jan 21, 2025	William Keating	D	House	Purchase	$1,001 - $15,000
Jan 15, 2025	Julie Johnson	D	House	Sale	$1,001 - $15,000