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CSGPIndustrialsCommon Stock

Costar Group, Inc

Held by 11 tracked managers as of Q2 2026 · CUSIP ⓘCUSIP: A 9-character ID for one specific security - one share class of one company, or one bond. Tickers can change and can mean different things in different countries; a CUSIP always identifies exactly the same security, which is why filings use it. Guide 22160N109 · Sector ⓘGICS sectors: The 11-sector system most investors know (Global Industry Classification Standard): Technology, Health Care, Financials and so on. This site assigns each company a GICS-style sector from its SIC code, with a few hand corrections, so sector pages match the names investors expect. Guide

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In plain English: 11 of the investors we track own this stock. In the latest quarter, 6 of them bought more of it and 7 sold some or all of theirs (2 bought it for the first time). That tells you what they did last quarter — not what the stock will do next.

Educational and informational only, not personalized investment advice. Based on public filings that may be delayed or contain errors; verify with the original filings. Disclaimer

Managers holding
11
-1 vs last quarter (like-for-like)
Total value held
$1.84B
Across tracked managers
Average weight ⓘOn average, how big this stock is in the portfolios that own it (its share of each manager's reported portfolio value).
0.9%
Of each manager's book
QoQ value ⓘLike-for-like: only managers that filed both quarters are compared, so a manager filing late (or confidentially) does not look like buying or selling. Includes price changes.
-$854.33M
-33.8% vs last quarter
Net shares bought
-3.6M
Est. net flow -$129.91M
Quarter activity
6 bought · 7 sold
2 new · 3 sold out

Tracked capital in this stock

Total value held (area) and number of managers (line). Dips can mean a large holder filed that quarter confidentially (e.g. Norges Bank in Q1/Q3).

Chart: Tracked capital in this stock

Aggregate buying and selling

Net share change reported each quarter

Chart: Aggregate buying and selling

Who owns CSGP?

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Who owns CSGP? — Q2 2026

Holders ranked by position size, with each one's quarter-over-quarter change.

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

# Manager Fund Shares Value ↓ % of their portfolio QoQ Δ shares Δ shares % Est. Δ value ⓘChange in shares × this quarter's price
1 Ron Baron Baron Capital (BAMCO) 21.63M $612.47M 0.9% Added +5.3M +32.6% +$150.45M
2 Baillie Gifford Baillie Gifford & Co 13.15M $372.53M 0.3% Reduced -456.8K -3.4% -$12.94M
3 Chuck Akre Akre Capital Management 11.70M $331.33M 6.5% Added +1.4M +13.1% +$38.26M
4 Polen Capital Polen Capital Management 8.76M $248.06M 2.1% Reduced -3.8M -30.3% -$107.93M
5 Norges Bank Norges Bank Investment Management 5.95M $168.50M 0.0% — — — —
6 Two Sigma Two Sigma Investments 1.10M $31.29M 0.0% Added +801.9K +264.7% +$22.71M
7 David Shaw D.E. Shaw & Co. 1.04M $29.55M 0.0% Reduced -4.9M -82.3% -$137.81M
8 Israel Englander Millennium Management 747.00K $21.15M 0.0% Added +623.4K +504.4% +$17.65M
9 Ken Griffin Citadel Advisors 741.90K $21.01M 0.0% Reduced -346.3K -31.8% -$9.81M
10 Steve Cohen Point72 Asset Management 130.62K $3.70M 0.0% New +130.6K — +$3.70M
11 Jeremy Grantham GMO 24.56K $695.65K 0.0% New +24.6K — +$695.65K

Sold out completely this quarter

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

Manager Fund Shares sold Value last quarter ↓
Chase Coleman Tiger Global Management -1.5M $60.51M
Keith Meister Corvex Management -851.7K $34.36M
Select Equity Group Select Equity Group -767 $30.94K

Politician trades

Politician trades in CSGP

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

Politician Date Ticker Asset Type Reported range ⓘThe dollar range the politician reported. Exact amounts are not disclosed. Est. size ⓘOur estimate only: the midpoint of the reported range. Owner Account ⓘSubholding Of: the account the trade was in, as named on the report (e.g. an IRA or a brokerage account). The same stock bought on the same day in different accounts is a separate trade in each account. Filed ↑ Filing delay ⓘDays between the trade and the report. Over 45 days is late under the STOCK Act. Source
Ro Khanna Politician Apr 23, 2024 CSGP COSTAR GROUP, INC. CMN scanned Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Spouse — May 6, 2024 13 days PTR ↗
Ro Khanna Politician Aug 5, 2024 CSGP COSTAR GROUP, INC. CMN scanned Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) — — Sep 6, 2024 32 days PTR ↗
Ro Khanna Politician Aug 2, 2024 CSGP COSTAR GROUP, INC. CMIN scanned Sale (partial) $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) — — Sep 6, 2024 35 days PTR ↗
Ro Khanna Politician Aug 2, 2024 CSGP COSTAR GROUP, INC. CMN scanned Sale (partial) $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Spouse — Sep 6, 2024 35 days PTR ↗
Ro Khanna Politician Jan 17, 2025 CSGP COSTAR GROUP, INC. CMN scanned Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Spouse — Feb 6, 2025 20 days PTR ↗
Julie Johnson Politician Jan 15, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Sale $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Joint Merrill Lynch Tax Efficient Core Feb 12, 2025 28 days PTR ↗
William R. Keating Politician Jan 21, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Self Bill's IRA Feb 25, 2025 35 days PTR ↗
Jefferson Shreve Politician Feb 24, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Purchase $15,001 - $50,000 Est. $32,500 (midpoint of reported range $15,001–$50,000) Self CRT - Standard Unit Trust Mar 9, 2025 13 days PTR ↗
Ro Khanna Politician Mar 12, 2025 CSGP COSTAR GROUP, INC. CMN scanned Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) — — Apr 10, 2025 29 days PTR ↗
Robert P. Bresnahan, Jr. Politician May 15, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Sale $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Self JP Morgan Brokerage Account May 31, 2025 16 days PTR ↗
Jefferson Shreve Politician May 12, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Sale $15,001 - $50,000 Est. $32,500 (midpoint of reported range $15,001–$50,000) Self CRT - Standard Unit Trust Jun 22, 2025 41 days PTR ↗
Gil Cisneros Politician Jun 27, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Purchase $15,001 - $50,000 Est. $32,500 (midpoint of reported range $15,001–$50,000) Self 150 Main Street Trust > Bank of America Jul 10, 2025 13 days PTR ↗
Gil Cisneros Politician Jun 30, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Self 150 Main Street Trust > Bank of America Jul 10, 2025 10 days PTR ↗
Gil Cisneros Politician Jun 25, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Self 150 Main Street Trust > Bank of America Jul 10, 2025 15 days PTR ↗
Gil Cisneros Politician Jul 31, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Self 150 Main Street Trust > Bank of America Aug 14, 2025 14 days PTR ↗
Gil Cisneros Politician Jul 9, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Self — Aug 14, 2025 36 days PTR ↗
Lisa McClain Politician Aug 13, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Spouse Charles Schwab Brokerage Account 924 Sep 12, 2025 30 days PTR ↗
Gil Cisneros Politician Sep 30, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Self 150 Main Street Trust > Bank of America Oct 10, 2025 10 days PTR ↗
Gil Cisneros Politician Sep 22, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Self 150 Main Street Trust > Bank of America Oct 10, 2025 18 days PTR ↗
Lisa McClain Politician Sep 25, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Sale $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Spouse Charles Schwab Brokerage Account 924 Oct 22, 2025 27 days PTR ↗
Gil Cisneros Politician Oct 15, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Self 150 Main Street Trust > Bank of America Nov 18, 2025 34 days PTR ↗
Ro Khanna Politician Nov 3, 2025 CSGP CMN COSTAR GROUP, INC. CMN scanned Sale (partial) $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) — — Dec 8, 2025 35 days PTR ↗
Ro Khanna Politician Dec 5, 2025 CSGP COSTAR GROUP, INC. CMN scanned Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) — — Jan 6, 2026 32 days PTR ↗
Ro Khanna Politician Dec 12, 2025 CSGP COSTAR GROUP, INC. CMN scanned Purchase — — Spouse — Jan 6, 2026 25 days PTR ↗
Gil Cisneros Politician Dec 10, 2025 CSGP CoStar Group, Inc. - Common Stock (CSGP) [ST] Purchase $1,001 - $15,000 Est. $8,000 (midpoint of reported range $1,001–$15,000) Self 150 Main Street Trust > Bank of America Jan 12, 2026 33 days PTR ↗