CoStar Group, Inc. (CSGP) Insider Trading
Over the last 3 months, CSGP insiders made 2 open-market buys and 0 sales, a net purchase of $2.5M (SEC Form 4). Over the last 6 months, 604 institutions increased and 673 reduced their position (13F).
Insider Activity
Sentiment
100/100
Buys (3m)
2
Sells (3m)
0
Net (3m)
$2.5M
Insiders buying
Insider trades by month Buys Sells
Jun
Jul
Sep
Nov
Mar
May
Context3-month price -29.8%Institutions mixed (13F)
| Date | Insider | Type | Shares | Price |
|---|---|---|---|---|
| Jun 24, 2026 | McCarthy Christine Mdirector | Grant | 8,262 | — |
| Jun 24, 2026 | Sams Louise Sdirector | Grant | 8,262 | — |
| Jun 24, 2026 | Hill John Wdirector | Grant | 8,262 | — |
| Jun 24, 2026 | Brunner Angelique G.director | Grant | 8,262 | — |
| Jun 24, 2026 | Musslewhite Robert Wdirector | Grant | 8,262 | — |
| Jun 24, 2026 | Glaser Rachel Cdirector | Grant | 8,262 | — |
| Jun 24, 2026 | BERISFORD JOHN Ldirector | Grant | 8,262 | — |
| Jun 16, 2026 | Cann Cynthia Cammettofficer: Chief Accounting Officer | Tax | 461 | $32.04 |
| May 4, 2026 | FLORANCE ANDREW Cdirector, officer: President and CEO | Buy | 3,100 | $35.82 |
| May 4, 2026 | FLORANCE ANDREW Cdirector, officer: President and CEO | Buy | 68,330 | $35.17 |
| Mar 17, 2026 | DESMARAIS MICHAEL Jofficer: Chief Human Resources Officer | Tax | 2,873 | $43.63 |
| Mar 17, 2026 | Boxer Geneofficer: General Counsel and Secretary | Tax | 428 | $43.63 |
| Mar 17, 2026 | Boxer Geneofficer: General Counsel and Secretary | Tax | 482 | $43.63 |
| Mar 17, 2026 | SIMURO FRANKofficer: Chief Technology Officer | Tax | 11,107 | $43.63 |
| Mar 17, 2026 | Cann Cynthia Cammettofficer: Chief Accounting Officer | Tax | 1,194 | $43.63 |
| Mar 17, 2026 | Ruggles Lisaofficer: Senior VP, Global Operations | Tax | 2,977 | $43.63 |
| Mar 11, 2026 | DESMARAIS MICHAEL Jofficer: Chief Human Resources Officer | Grant | 17,676 | $46.34 |
| Mar 11, 2026 | Cann Cynthia Cammettofficer: Chief Accounting Officer | Grant | 4,374 | $46.34 |
| Mar 11, 2026 | Boxer Geneofficer: General Counsel and Secretary | Grant | 21,920 | $46.34 |
| Mar 11, 2026 | LOWN CHRISTIAN M.officer: Chief Financial Officer | Grant | 12,268 | $46.34 |
| Mar 11, 2026 | FLORANCE ANDREW Cdirector, officer: President and CEO | Grant | 124,162 | $46.34 |
| Mar 9, 2026 | Sams Louise Sdirector | Buy | 1,000 | $48.36 |
| Mar 3, 2026 | FLORANCE ANDREW Cdirector, officer: President and CEO | Tax | 59,593 | $44.63 |
| Mar 3, 2026 | SAINT FREDERICK G.officer: President, Marketplaces | Grant | 39,652 | — |
| Mar 3, 2026 | Cann Cynthia Cammettofficer: Chief Accounting Officer | Grant | 6,834 | — |
| Mar 3, 2026 | Boxer Geneofficer: General Counsel and Secretary | Grant | 26,888 | — |
| Mar 3, 2026 | FLORANCE ANDREW Cdirector, officer: President and CEO | Grant | 83,708 | — |
| Mar 3, 2026 | LOWN CHRISTIAN M.officer: Chief Financial Officer | Grant | 39,652 | — |
| Mar 3, 2026 | Boxer Geneofficer: General Counsel and Secretary | Tax | 4,547 | $44.63 |
| Mar 3, 2026 | SIMURO FRANKofficer: Chief Technology Officer | Tax | 18,702 | $44.63 |
Source: CSGP SEC Form 4 filings, latest Jun 24, 2026. For informational purposes only — not investment advice.
Institutional activity (13F)
How institutions changed their CSGP positions over the last 6 months (SEC Form 13F).
Increased
604
New positions
232
Reduced
673
Sold out
314
Largest moves
| Institution | Action | Shares | Filed |
|---|---|---|---|
| VANGUARD GROUP INC | Increased | 70.1M | Jan 29, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | New Position | 54.8M | May 15, 2026 |
| VANGUARD PORTFOLIO MANAGEMENT LLC | New Position | 38.2M | May 8, 2026 |
| BLACKROCK, INC. | Reduced | 34.0M | Feb 12, 2026 |
| BLACKROCK, INC. | Reduced | 33.8M | May 13, 2026 |
| BAMCO INC /NY/ | Increased | 19.5M | Feb 17, 2026 |
| STATE STREET CORP | Increased | 18.7M | May 15, 2026 |
| STATE STREET CORP | Increased | 18.6M | Feb 13, 2026 |
| PRINCIPAL FINANCIAL GROUP INC | Increased | 17.7M | May 4, 2026 |
| PRINCIPAL FINANCIAL GROUP INC | Reduced | 17.6M | Feb 2, 2026 |
| BAMCO INC /NY/ | Reduced | 16.3M | May 15, 2026 |
| CAPITAL INTERNATIONAL INVESTORS | Increased | 15.5M | May 13, 2026 |
| JANUS HENDERSON GROUP PLC | Increased | 15.4M | May 18, 2026 |
| BAILLIE GIFFORD & CO | Increased | 13.6M | May 8, 2026 |
| BAILLIE GIFFORD & CO | Increased | 12.9M | Jan 23, 2026 |
Source: SEC Form 13F filings. For informational purposes only — not investment advice.