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COSTAR GROUP INC (CSGP)

Name: COSTAR GROUP INC (CSGP) — Institutional ownership, SEC filings and insider activity
Creator: Sightfile
License: https://www.sec.gov/privacy#dissemination

Institutional ownership, SEC filings and insider activity

Sector: Professional Services · SEC CIK 0001057352 · EDGAR filings · Updated 2026-07-28

COSTAR GROUP INC (CSGP) has reported institutional ownership of 99.6%, with 787 institutional managers holding positions valued at $16.4B per the latest 13F reporting period.

Institutional ownership

99.6%

Institutional managers

787

Reported 13F value

$16.4B

Insider activity

53 trans.

−$3.61M net selling

Filings this week (1)

2026-07-28 — Current report (8-K) filed

Every filing links to the official SEC document. Real-time filing alerts for this company are available inside the app.

Latest updates

2026-07-13 — Current report (8-K) filed
2026-07-06 — Insider transaction reported (Form 4)
2026-06-25 — Current report (8-K) filed
2026-06-24 — Insider transaction reported (Form 4)
2026-06-24 — Insider transaction reported (Form 4)
2026-06-24 — Insider transaction reported (Form 4)
2026-06-24 — Insider transaction reported (Form 4)
2026-06-24 — Insider transaction reported (Form 4)

Institutional ownership overview

According to SEC 13F filings tracked by Sightfile, COSTAR GROUP INC has 787 institutional holders and institutional ownership of 99.6%.

#	Institution	Reported value	% of tracked total
1	VANGUARD PORTFOLIO MANAGEMENT LLC	$1.54B	9.4%
2	BlackRock, Inc.	$1.36B	8.3%
3	VANGUARD CAPITAL MANAGEMENT LLC	$1.11B	6.7%
4	STATE STREET CORP	$752.4M	4.6%
5	PRINCIPAL FINANCIAL GROUP INC	$713.9M	4.3%
6	BAMCO INC /NY/	$658.1M	4.0%
7	Capital International Investors	$625.8M	3.8%
8	BAILLIE GIFFORD & CO	$549.1M	3.3%
9	POLEN CAPITAL MANAGEMENT LLC	$507.1M	3.1%
10	GEODE CAPITAL MANAGEMENT, LLC	$500.4M	3.0%

Full holder history and quarter-over-quarter changes are available inside the app.

Insider activity

Insiders reported 53 transactions (4 buys, 6 sells) across 15 reporting insiders, with a net reported value of −$3.61M.

Quarterly net insider value, as reported in Form 4 filings.

Fails-to-deliver

The SEC's fails-to-deliver file for 2026-06-22 reports 35,999 failed-to-deliver shares ($786.3K) for CSGP — an official data point published by the SEC, shown as reported.

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See full history, cross-references and alerts on Sightfile

Sightfile provides information only — not investment advice, recommendations, or an assessment of any security. Data is derived from official public sources (SEC EDGAR and U.S. government agencies), may contain errors or delays, and should be verified against the source filing before relying on it.
Data sources: SEC EDGAR (filings, 13F, FTD), aggregated by Sightfile. Page updated 2026-07-28.