NASDAQ:CSGP

Costar Group Stock Insider Trading

Real Estate > Real Estate - Services

Buy CSGP

*Your capital is at risk

$33.40

-0.260 (-0.772%)

At Close: Jun 03, 2026

CoStar Group Stock Insider Power

Based on the 100 latest insides trades, we have calculated the insider power to be negative at -9.06. In total, the insiders bought 668.92K and sold 567.31K CSGP shares in the last 100 trades. The insider score can be negative despite buy/sell ratio being positive. The score focuses on the quality of the trades.

Insider Power (Last 100 transactions)	-9.06
● Buy	668.92K shares
● Sell	567.31K shares
41% Buy Activity Negligible or No Correlation
Buy Signal Low Confidence May 01, 2026 Analysis Breakdown: Weakened by a contradictory negative Insider Power Score. Confidence increased due to high data reliability score of 100.

Historical Insider Trades

Date	Type	Person	Role	Amount
May 01, 2026 Buy	Common Stock, par value $0.01 per share P-Purchase	Florance Andrew C President And CEO	CEO / President	68 330 Value: $2.40M
May 01, 2026 Buy	Common Stock, par value $0.01 per share P-Purchase	Florance Andrew C President And CEO	CEO / President	3 100 Value: $111.0K
Mar 15, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Simuro Frank Chief Technology Officer	Officer	11 107 Value: $484.6K
Mar 15, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Boxer Gene General Counsel And Secretary	Officer	428 Value: $18.7K
Mar 15, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Ruggles Lisa Senior Vp, Global Operations	Officer	2 977 Value: $129.9K
Mar 15, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Boxer Gene General Counsel And Secretary	Officer	482 Value: $21.0K
Mar 15, 2026 Buy	Common Stock J-Other	Banerjee Nana	Director	0 Value: $0
Mar 15, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Desmarais Michael J Chief Human Resources Officer	Officer	2 873 Value: $125.3K
Mar 15, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Cann Cynthia Cammett Chief Accounting Officer	Officer	1 194 Value: $52.1K
Mar 10, 2026 Buy	Common Stock, par value $0.01 per share A-Award	Cann Cynthia Cammett Chief Accounting Officer	Officer	4 374 Value: $202.7K
Mar 10, 2026 Buy	Common Stock, par value $0.01 per share A-Award	Florance Andrew C President And CEO	CEO / President	124 162 Value: $5.75M
Mar 10, 2026 Buy	Common Stock, par value $0.01 per share A-Award	Lown Christian M. Chief Financial Officer	C-Suite Officer	12 268 Value: $568.5K
Mar 10, 2026 Buy	Common Stock, par value $0.01 per share A-Award	Boxer Gene General Counsel And Secretary	Officer	21 920 Value: $1.02M
Mar 10, 2026 Buy	Common Stock, par value $0.01 per share A-Award	Desmarais Michael J Chief Human Resources Officer	Officer	17 676 Value: $819.1K
Mar 06, 2026 Buy	Common Stock, par value $0.01 per share P-Purchase	Sams Louise S Director	Director	1 000 Value: $48.4K
Mar 02, 2026 Buy	Common Stock, par value $0.01 per share P-Purchase	Saint Frederick G. President, Marketplaces	CEO / President	20 000 Value: $906.6K
Mar 02, 2026 Buy	Common Stock, par value $0.01 per share P-Purchase	Glaser Rachel C Director	Director	1 000 Value: $44.9K
Mar 01, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Simuro Frank Chief Technology Officer	Officer	18 702 Value: $834.7K
Mar 01, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Ruggles Lisa Senior Vp, Global Operations	Officer	8 931 Value: $398.6K
Mar 01, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Cann Cynthia Cammett Chief Accounting Officer	Officer	1 385 Value: $61.8K
Mar 01, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Desmarais Michael J Chief Human Resources Officer	Officer	6 353 Value: $283.5K
Mar 01, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Boxer Gene General Counsel And Secretary	Officer	4 547 Value: $202.9K
Mar 01, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Lown Christian M. Chief Financial Officer	C-Suite Officer	7 175 Value: $320.2K
Mar 01, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Florance Andrew C President And CEO	CEO / President	59 593 Value: $2.66M
Mar 01, 2026 Sell	Common Stock, par value $0.01 per share F-InKind	Saint Frederick G. President, Marketplaces	CEO / President	11 096 Value: $495.2K

About Insider Power

Insider Power is a proprietary algorithm developed by StockInvest.us to evaluate the significance of insider transactions. The calculation considers the size, type, and timing of transactions, as well as the insider’s role within the company.

It is important to note that, in general, there is little to no correlation between insider transactions and short-term stock price movements. In one of our studies, only 0.22%^* of stocks with insider activity showed a measurable correlation — and even then, it was unclear whether the effect was caused by insider actions or simply by the stock’s broader trend.

While our algorithms are designed to highlight potentially meaningful signals, these cannot be regarded as statistically significant on their own. Insider trading activity should therefore be seen as informative rather than as direct trading guidance. The Insider Power metric was created to present this information in a clearer and more accessible way, helping investors better understand the possible context of insider activity.

* October 6th, 2025 - Tested on 5562 stocks

ABOUT COSTAR GROUP

CoStar Group, Inc. provides information, analytics, and online marketplace services to the commercial real estate, hospitality, residential, and related professionals industries in the United States, Canada, Europe, the Asia Pacific, and Latin America. It offers CoStar Property that provides inventory of office, industrial, retail, multifamily, hospitality, and student housing properties and land; CoStar COMPS, a robust database of comparable com...

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