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CSGP

CoStar Group, Inc. Common Stoc

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CSGP in the last 90 days

CoStar Group, Inc. Common Stoc (CSGP) had 1 congress transaction by 1 member and 1 insider purchase worth $2,489,837 by 1 insider in filings from the last 90 days.

FINRA’s latest report (settlement 15 SEPT 2026) shows 14,839,529 shares held short, 2.7 days to cover, down 21.5% from the report before.

  • Congress: 1 purchase and 0 sales reported, amounts in the bands the law requires.
  • Insiders: open-market purchases only (Form 4 code P); a purchase filed by related owners counts once.
  • Delay: each filing below shows how many days passed between the trade and its publication. None of this is real-time.

Latest filing on file: 10 SEPT 2026 · FINRA settlement 15 SEPT 2026 · public filings, reported as filed

What the price is doing

$28$41 → $28 · -33% over six months

CSGP is down 33%, and short sellers have been backing off.

Bets against it — they pay off if the price falls — are down 11% over the same stretch.

$41 STARTAPRMAYJUNJULAUGSEPTOCT04 AUG 2026 — FLORANCE ANDREW C — $2,489,83714 APR 2026 — Hon. Gilbert Cisneros — $1,001 – $15,000 · partial19 AUG 2026 — Hon. Gilbert Cisneros — $1,001 – $15,000NOW $28

Politician & insider activityBoughtSold

Short sellers

11 reports · twice a month

APR 0%peak +14%15 SEPT -11%APRMAYJUNJULAUGSEPTOCT

Money betting CSGP falls. Reported twice a month, and it shows up seven working days late.

Politicians

1 buys · 1 sales

Traded over six months

View activity →

Short sellers

Bets down 11%

Over six months · newest 15 SEPT 2026

See the numbers →

Insiders

1 reported

Traded over six months

See the filings →

Quiet Money

Our take on how well CSGP holds up when sellers show up.

How it holds up · last 60 trading days

Through 21 SEPT 2026

Vulnerable

When CSGP gets hit, it tends to drop more easily than usual.

Lately, CSGP has been easier to push down than usual.

That's been true for the last 19 trading days.

The last 6 months

ResilientMixedVulnerable
MAYJUNJULAUGSEPT
31 MAR 2026Now · 21 SEPT 2026

What the filings show

What the filings show · last 90 days

3 of 4 sources

+48Tilted in

Leaning outBalancedLeaning in

The disclosed money is leaning into this name, on what has actually been filed. Four sources agree on the picture.

Short interest
Short interest fell 9.1% — 16,321,416 to 14,839,529 shares between 15 JUL 2026 and 15 SEPT 2026. See the filings →
+23
Insider purchases
1 insider disclosed buying $2,489,837 across 1 filing.
+46
Congress
1 member of Congress disclosed 1 purchase and 0 sales. See the filings →
+100

This summarises filings that have already been published — it is not a forecast, a rating of the company, or advice. Every figure above is listed in full further down this page, with the document it came from.

FINRA short interest

Settlement 15 SEPT 2026 · shares held short

14,839,529shares held short

Days to cover

2.68

Avg daily volume

5,527,541

Since last report

-21.49%

As of 15 September 2026, 14,839,529 CoStar Group, Inc. Common Stoc shares were held short — the total across every reporting firm, not one fund's position. That is 4,062,229 shares fewer than the previous report, a 21.49% decrease. At the average daily volume of 5,527,541 shares, that position represents 2.68 days of trading — what the filing calls days to cover.

This is the most recent figure that exists, and it is 17 days old. FINRA collects short interest twice a month, on a settlement date, and publishes it about eight business days later. So nobody has a live short-interest number for CSGP — not us, and not anyone quoting one. We print the settlement date on the figure so you always know which day you are looking at.

Across the 12 reports we hold, the position has fallen from 21,977,041 shares on 31 March 2026 to 14,839,529 today, a change of 32.5%. The highest reading in that window was 21,977,041 shares on 31 March 2026.

SettlementShares shortDays to cover
15 SEPT 202614,839,5292.68
31 AUG 202618,901,7582.51
14 AUG 202616,691,3792.79
31 JUL 202616,312,4121.92
15 JUL 202616,321,4162.45
30 JUN 202615,266,3391.90
15 JUN 202617,109,2072.39
29 MAY 202615,095,7732.40
15 MAY 202618,639,6921.89
30 APR 202617,590,8542.79
15 APR 202616,639,8522.65
31 MAR 202621,977,0413.28
What is CSGP's short interest?
14,839,529 shares, as of the 15 September 2026 settlement date. That is the figure FINRA published, unadjusted.
What percentage of the float is short?
We do not publish that, because FINRA does not publish float. The regulator reports the number of shares held short; turning it into a percentage needs a share count from somewhere else, and different sources disagree about what counts as float. We would rather give you the number that was actually filed than a percentage built on an assumption.
How current is this?
It is 17 days old, and that is as fresh as short interest gets. FINRA measures it twice a month and publishes it seven business days after the settlement date. Any site showing you a "live" short interest figure is showing you something else.
What does days to cover mean?
It is the short position divided by average daily trading volume — here, 2.68. It describes how many days of ordinary trading the position is equivalent to. It is arithmetic from the filing, not a prediction about what will happen.
Where does this come from?
FINRA's consolidated short interest file, which is public. We read it directly and store it unchanged, except that we blank the days-to-cover placeholder FINRA writes when a stock has almost no volume.

Disclosed insider buying on file

$2,489,837across 1 purchase

Open-market purchases only — the amount is a fact, not a verdict.

On file here

Short positions0

Insider purchases1

Congress transactions20

Latest change10 SEPT 2026

SHORT POSITIONS · 0INSIDER BUYS · 1CONGRESS · 20

Insider purchases on file

  • SEC — Form 4 insider purchase

    FLORANCE ANDREW CDirector / Founder and CEO

    BOUGHTCommon Stock, par value $0.01 per share

    $2,489,837

    83,300 sh @ $29.89

    04 AUG 2026 → filed 05 AUG 2026

    Filed 1 day after the tradeSEC EDGAR · 0001628280-26-052968 →

Congress transactions on file

20 disclosed · newest first · every row links to its filing

WhoAmount as filedTradedFiledLag
Hon. Gilbert CisnerosBOUGHT$1,001 – $15,00019 AUG 202610 SEPT 202622 days
Hon. Gilbert CisnerosSOLD$1,001 – $15,000 · partial14 APR 202608 MAY 202624 days
Hon. Gilbert CisnerosBOUGHT$1,001 – $15,00013 MAR 202607 APR 202625 days
Hon. Gilbert CisnerosBOUGHT$1,001 – $15,00028 JAN 202613 FEB 202616 days
Hon. Gilbert CisnerosBOUGHT$1,001 – $15,00010 DEC 202512 JAN 202633 days
Hon. Gilbert CisnerosBOUGHT$1,001 – $15,00015 OCT 202518 NOV 202534 days
Hon. Lisa McClainSOLD$1,001 – $15,00025 SEPT 202522 OCT 202527 days
Hon. Gilbert CisnerosBOUGHT$1,001 – $15,00022 SEPT 202510 OCT 202518 days
Hon. Gilbert CisnerosBOUGHT$1,001 – $15,00030 SEPT 202510 OCT 202510 days
Hon. Lisa McClainBOUGHT$1,001 – $15,00013 AUG 202512 SEPT 202530 days
Hon. Gilbert CisnerosBOUGHT$1,001 – $15,00009 JUL 202514 AUG 202536 days
Hon. Gilbert CisnerosBOUGHT$1,001 – $15,00031 JUL 202514 AUG 202514 days
Hon. Gilbert CisnerosBOUGHT$1,001 – $15,00030 JUN 202510 JUL 202510 days
Hon. Gilbert CisnerosBOUGHT$1,001 – $15,00025 JUN 202510 JUL 202515 days
Hon. Gilbert CisnerosBOUGHT$15,001 – $50,00027 JUN 202510 JUL 202513 days
Hon. Jefferson ShreveSOLD$15,001 – $50,00012 MAY 202522 JUN 202541 days
Hon. Rob BresnahanSOLD$1,001 – $15,00015 MAY 202531 MAY 202516 days
Hon. Jefferson ShreveBOUGHT$15,001 – $50,00024 FEB 202509 MAR 202513 days
Hon. William R. KeatingBOUGHT$1,001 – $15,00021 JAN 202525 FEB 202535 days
Hon. Julie JohnsonSOLD$1,001 – $15,00015 JAN 202512 FEB 202528 days
What this page will never showNo price targetsNo score out of 100No buy or sell callsNo predictionsDocuments, dates, and how late they were.