CSGPNasdaq · Services-Business Services, NEC

COSTAR GROUP, INC.

Alert me on CSGP

Insider buys, 6 months

Congress trades, 6 months

Signals, 6 months

Six months

After each filing

Sep 10 Buy Rep. Gilbert Cisneros House

1 week

−4.5%S&P −0.1%

1 month

−4.1%S&P +2.1%

3 months

Result in33 trading days

6 months

Result in96 trading days

Aug 11 Sale Hill John W Insider

1 week

+0.8%S&P −0.4%

1 month

−5.2%S&P −1.7%

3 months

Result in11 trading days

6 months

Result in74 trading days

Aug 11 Sale Cann Cynthia Cammett Insider

1 week

+0.8%S&P −0.4%

1 month

−5.2%S&P −1.7%

3 months

Result in11 trading days

6 months

Result in74 trading days

Aug 5 Buy FLORANCE ANDREW C Insider

1 week

+1.0%S&P +0.4%

1 month

+4.9%S&P +0.4%

3 months

Result in7 trading days

6 months

Result in70 trading days

May 8 Sale Rep. Gilbert Cisneros House

1 week

+0.9%S&P −0.1%

1 month

+4.0%S&P −1.9%

3 months

−5.5%S&P +4.5%

6 months

Result in11 trading days

Show all 27

May 4 Buy FLORANCE ANDREW C Insider

1 week

−7.0%S&P +3.0%

1 month

−5.6%S&P +5.0%

3 months

−15.7%S&P +7.7%

6 months

Result in6 trading days

Apr 7 Buy Rep. Gilbert Cisneros House

1 week

+1.3%S&P +3.5%

1 month

−9.9%S&P +8.2%

3 months

−24.8%S&P +11.5%

6 months

−28.9%S&P +15.6%

Mar 9 Buy Sams Louise S Insider

1 week

−9.9%S&P −1.4%

1 month

−19.8%S&P −0.1%

3 months

−31.0%S&P +9.3%

6 months

−37.3%S&P +13.5%

Mar 4 Buy SAINT FREDERICK G. Insider

1 week

−4.7%S&P −1.3%

1 month

−16.1%S&P −4.0%

3 months

−29.8%S&P +10.4%

6 months

−34.3%S&P +12.3%

Mar 4 Buy Glaser Rachel C Insider

1 week

−4.7%S&P −1.3%

1 month

−16.1%S&P −4.0%

3 months

−29.8%S&P +10.4%

6 months

−34.3%S&P +12.3%

Mar 3 Buy FLORANCE ANDREW C Insider

1 week

−1.0%S&P −0.5%

1 month

−15.3%S&P −3.4%

3 months

−28.0%S&P +12.0%

6 months

−31.6%S&P +12.6%

Feb 13 Buy Rep. Gilbert Cisneros House

1 week

+7.5%S&P +0.7%

1 month

−5.7%S&P −3.1%

3 months

−27.4%S&P +8.5%

6 months

−31.4%S&P +13.0%

Jan 12 Buy Rep. Gilbert Cisneros House

1 week

+4.8%S&P −1.2%

1 month

−27.2%S&P −1.8%

3 months

−36.4%S&P +1.2%

6 months

−50.9%S&P +8.8%

Nov 18, 2025 Buy Rep. Gilbert Cisneros House

1 week

+2.7%S&P +2.6%

1 month

−1.2%S&P +3.0%

3 months

−27.5%S&P +3.3%

6 months

−48.6%S&P +13.2%

Nov 18, 2025 Sale Cann Cynthia Cammett Insider

1 week

+3.6%S&P +2.3%

1 month

−2.9%S&P +2.5%

3 months

−25.4%S&P +4.8%

6 months

−49.2%S&P +13.2%

Nov 18, 2025 Sale Hill John W Insider

1 week

+3.6%S&P +2.3%

1 month

−2.9%S&P +2.5%

3 months

−25.4%S&P +4.8%

6 months

−49.2%S&P +13.2%

Oct 22, 2025 Sale Rep. Lisa McClain House

1 week

−10.3%S&P +1.2%

1 month

−13.4%S&P −1.9%

3 months

−15.3%S&P +3.4%

6 months

−53.3%S&P +7.1%

Oct 10, 2025 Buy Rep. Gilbert Cisneros House

1 week

−0.3%S&P +1.2%

1 month

−9.0%S&P +3.0%

3 months

−17.8%S&P +4.9%

6 months

−47.7%S&P +6.2%

Sep 12, 2025 Buy Rep. Lisa McClain House

1 week

−3.0%S&P +1.2%

1 month

−14.9%S&P +0.5%

3 months

−23.3%S&P +3.4%

6 months

−50.3%S&P +2.1%

Sep 3, 2025 Sale SAINT FREDERICK G. Insider

1 week

−1.8%S&P +1.3%

1 month

−4.5%S&P +4.2%

3 months

−22.4%S&P +6.2%

6 months

−44.3%S&P +6.4%

Aug 14, 2025 Buy Rep. Gilbert Cisneros House

1 week

+1.7%S&P +0.3%

1 month

−1.7%S&P +2.6%

3 months

−23.6%S&P +4.7%

6 months

−49.0%S&P +6.7%

Jul 10, 2025 Buy Rep. Gilbert Cisneros House

1 week

−0.9%S&P +0.6%

1 month

+8.3%S&P +2.0%

3 months

−9.3%S&P +7.9%

6 months

−31.5%S&P +11.9%

Jun 22, 2025 Sale Rep. Jefferson Shreve House

1 week

+0.4%S&P +2.9%

1 month

+13.7%S&P +5.7%

3 months

+7.8%S&P +11.4%

6 months

−18.5%S&P +14.0%

May 31, 2025 Sale Rep. Rob Bresnahan House

1 week

+7.7%S&P +1.2%

1 month

+11.1%S&P +5.0%

3 months

+20.3%S&P +8.3%

6 months

−7.2%S&P +15.4%

Mar 9, 2025 Buy Rep. Jefferson Shreve House

1 week

+0.3%S&P +1.2%

1 month

−8.4%S&P −11.2%

3 months

−1.2%S&P +7.3%

6 months

+10.3%S&P +16.7%

Feb 25, 2025 Buy Rep. William R. Keating House

1 week

+1.2%S&P −1.9%

1 month

+4.2%S&P −4.3%

3 months

−3.5%S&P −0.8%

6 months

+16.3%S&P +9.4%

Feb 12, 2025 Sale Rep. Julie Johnson House

1 week

+4.4%S&P −1.6%

1 month

+9.0%S&P −7.0%

3 months

+3.4%S&P −2.9%

6 months

+21.9%S&P +6.2%

Every purchase and sale on this ticker reported by a member of Congress or an insider, measured from the close of the first trading day after it became public to the close 1 week, 1 month, 3 months and 6 months later, each beside the S&P over the same days.

Filings for CSGP

80 held · newest 580 held · newest 2

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See all 80 filings for CSGP

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New sources, new features and offers like our founding price. A few times a month at most. Stop any time.

Signal history

No signal for this ticker yet. A signal is written when insider buying here scores one dot or more.

Stakes

Jun 30, 2026 Schedule 13G

Baron Capital Group, Inc.: 5.3%, 21,626,763 shares

Mar 31, 2026 Schedule 13G

Vanguard Capital Management: 7.5%, 31,613,997 shares

Mar 31, 2026 Schedule 13G

Vanguard Portfolio Management: 9.1%, 38,292,035 shares

Mar 13, 2026 Schedule 13G, amended

The Vanguard Group: 0%, 0 shares

Schedule 13D is filed within 5 business days of crossing 5 percent by an investor who may seek to influence the company. Schedule 13G is filed by a passive holder, and a large institution has up to 45 days after the quarter end.

Government contracts, last 12 months

Awards of $10M and up, from USAspending · context, not a signal

No contracts of $10M or more in the last 12 months.

Lobbying

Last four quarters

$120KQ4 2025

$120KQ1 2026

$210KQ2 2026

$230KQ3 2026

Up 10 percent from Q2 2026. Reported to the Senate each quarter by the firms it hires.Original report ↗

Read from LDA.gov between Sep 23, 2026 and Oct 21, 2026. Senate Office of Public Records cannot vouch for the data or analyses derived from these data after the data have been retrieved from LDA.gov.