Company · Ownership research

COSTAR GROUP, INC. CSGP

CIK 0001057352 · CUSIP 22160N109

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 22160N109 (CSGP), not CUSIP 22160N909 (CSGP), CUSIP 22160N959 (CSGP), and does not merge CUSIPs.

This page lists the top 20 of 796 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	VANGUARD PORTFOLIO MANAGEMENT LLC CIK 2100121 · Amended · View history	$1.54B 38,234,133 shares	0.08%	—	SEC filing ↗ May 8, 2026	▾
02	BlackRock, Inc. CIK 2012383 · View history	$1.36B 33,808,184 shares	0.02%	-162.44K(-0.50%)Reduced	SEC filing ↗ May 13, 2026	▾
03	VANGUARD CAPITAL MANAGEMENT LLC CIK 2100119 · Amended · View history	$1.11B 27,423,903 shares	0.03%	—	SEC filing ↗ May 15, 2026	▾
04	STATE STREET CORP CIK 93751 · View history	$752.38M 18,650,975 shares	0.03%	+18.62K(+0.10%)Added	SEC filing ↗ May 15, 2026	▾
05	PRINCIPAL FINANCIAL GROUP INC CIK 1126328 · View history	$713.87M 17,696,192 shares	0.38%	+130.12K(+0.70%)Added	SEC filing ↗ May 4, 2026	▾
06	BAMCO INC /NY/ CIK 1017918 · View history	$658.11M 16,314,175 shares	1.99%	-3.18M(-16.30%)Reduced	SEC filing ↗ May 15, 2026	▾
07	Invesco Ltd. CIK 914208 · Amended · View history	$643.32M 15,947,525 shares	0.06%	+1.04M(+7.00%)Added	SEC filing ↗SEC filing ↗ May 12, 2026	▾
08	Capital International Investors CIK 1562230 · View history	$625.82M 15,513,753 shares	0.15%	+4.67M(+43.10%)Added	SEC filing ↗ May 13, 2026	▾
09	BAILLIE GIFFORD & CO CIK 1088875 · View history	$549.06M 13,610,922 shares	0.56%	+677.74K(+5.20%)Added	SEC filing ↗ May 8, 2026	▾
10	POLEN CAPITAL MANAGEMENT LLC CIK 1034524 · View history	$507.09M 12,570,368 shares	3.51%	+7.68M(+157.00%)Added	SEC filing ↗ May 14, 2026	▾
11	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$500.45M 12,448,652 shares	0.03%	+266.49K(+2.20%)Added	SEC filing ↗ May 15, 2026	▾
12	AKRE CAPITAL MANAGEMENT LLC CIK 1112520 · View history	$417.45M 10,348,273 shares	6.83%	+730.47K(+7.60%)Added	SEC filing ↗ May 14, 2026	▾
13	GOLDMAN SACHS GROUP INC CIK 886982 · View history	$372.98M 9,245,812 shares	0.05%	+5.49M(+146.50%)Added	SEC filing ↗ May 15, 2026	▾
14	JANUS HENDERSON GROUP PLC CIK 1274173 · Amended · View history	$311.59M 7,724,152 shares	0.15%	+250.77K(+3.40%)Added	SEC filing ↗ May 18, 2026	▾
15	D. E. Shaw & Co., Inc. CIK 1009207 · View history	$238.39M 5,909,623 shares	0.19%	+5.00M(+552.60%)Added	SEC filing ↗ May 15, 2026	▾
16	MORGAN STANLEY CIK 895421 · View history	$218.34M 5,412,615 shares	0.01%	+121.48K(+2.30%)Added	SEC filing ↗ May 15, 2026	▾
17	Capital Research Global Investors CIK 1422848 · View history	$176.44M 4,373,706 shares	0.03%	-1.19M(-21.40%)Reduced	SEC filing ↗ May 13, 2026	▾
18	BANK OF AMERICA CORP /DE/ CIK 70858 · View history	$143.94M 3,568,107 shares	0.01%	+63.30K(+1.80%)Added	SEC filing ↗ May 18, 2026	▾
19	VAN ECK ASSOCIATES CORP CIK 869178 · View history	$140.33M 3,478,726 shares	0.11%	+3.42M(+6,054.40%)Added	SEC filing ↗ May 15, 2026	▾
20	NORTHERN TRUST CORP CIK 73124 · View history	$138.46M 3,432,231 shares	0.02%	-33.83K(-1.00%)Reduced	SEC filing ↗ May 14, 2026	▾

Showing 20 / 796 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

796

Cancelled or null records excluded

Disclosed shares

415,794,725

Not deduplicated across managers

Disclosed value

$16.78B

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

COSTAR GROUP, INC. · Q1 2026

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This page includes 20 of 796 reporting institutions. Log in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.

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Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.