CoStar Group (CSGP) director purchases 1,000 shares in open market trade

Rhea-AI Filing Summary

COSTAR GROUP, INC. director Rachel C. Glaser reported an open-market purchase of 1,000 shares of common stock at a price of $44.94 per share. After this transaction, she directly owns 4,157 shares. The reported amount includes shares that were previously omitted from an earlier filing.

Insider Trade Summary

Net Buyer: 1,000 shares ($44,940)

Net Buy 1 txn

Insider Glaser Rachel C

Role Director

Bought 1,000 shs ($45K)

Type	Security	Shares	Price	Value
Purchase	Common Stock, par value $0.01 per share	1,000	$44.94	$45K

Holdings After Transaction: Common Stock, par value $0.01 per share — 4,157 shares (Direct)

Footnotes (1)

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Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Glaser Rachel C

(Last) (First) (Middle)

C/O COSTAR GROUP, INC.

1201 WILSON BLVD.

(Street)

ARLINGTON VA 22209

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
COSTAR GROUP, INC. [ CSGP ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
03/02/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock, par value $0.01 per share	03/02/2026		P		1,000	A	$44.94	4,157(1)	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. This amount includes shares that were inadvertently omitted from the insider's prior filing.

Remarks:

Exhibit 24 - Power of Attorney

	/s/ Gene Boxer, Attorney-in-Fact	03/03/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transaction did CoStar Group (CSGP) director Rachel Glaser report?

Rachel C. Glaser reported buying 1,000 CoStar Group shares in the open market at $44.94 each. This Form 4 filing reflects a direct ownership change and includes shares previously omitted from an earlier report.

At what price did the CoStar Group (CSGP) director purchase shares?

The director purchased CoStar Group common stock at $44.94 per share. This price reflects an open-market transaction, indicating she executed the trade at prevailing market levels rather than through a fixed-price award or option exercise.

How many CoStar Group (CSGP) shares does the director own after the transaction?

After the reported purchase, the director directly owns 4,157 CoStar Group shares. This total includes 1,000 newly bought shares plus additional shares that were inadvertently omitted from a prior insider ownership report and are now reflected.

What does the Form 4 footnote say about CoStar Group (CSGP) insider holdings?

The footnote states the reported amount includes shares inadvertently omitted from an earlier filing. This clarifies that some of the now-reported holdings existed previously but were not correctly disclosed, rather than all being newly purchased shares.

Was the CoStar Group (CSGP) insider transaction a buy or a sell?

The disclosed insider transaction was a buy, specifically an open-market purchase of 1,000 shares. The Form 4 uses transaction code “P,” confirming it as a purchase rather than a sale, gift, or option-related transaction.