CoStar (NASDAQ: CSGP) CTO gets 52,869 RSUs, 18,702 shares withheld

Rhea-AI Filing Summary

CoStar Group Chief Technology Officer Frank Simuro received a grant of 52,869 restricted stock units, each representing one future share of common stock. The units vest in three equal installments on March 1, 2027, 2028 and 2029. To cover tax obligations, 18,702 common shares were disposed of through a tax-withholding transaction at a price of $44.63 per share, leaving him with 425,598 common shares held directly.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider SIMURO FRANK

Role Chief Technology Officer

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock, par value $0.01 per share	18,702	$44.63	$835K
Grant/Award	Restricted Stock Units	52,869	$0.00	--

Holdings After Transaction: Common Stock, par value $0.01 per share — 425,598 shares (Direct); Restricted Stock Units — 52,869 shares (Direct)

Footnotes (1)

1. On February 27, 2026, the last preceding business day, the closing price of the Company's common stock on Nasdaq was $44.63. Each restricted stock unit represents a contingent right to receive one share of CoStar Group, Inc. common stock. The restricted stock units vest in three equal installments on March 1, 2027, March 1, 2028 and March 1, 2029.

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^*

SIMURO FRANK

(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)

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

3. Date of Earliest Transaction (Month/Day/Year)
02/27/2026

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	03/01/2026		F		18,702	D	$44.63(1)	425,598	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
Restricted Stock Units	(2)	02/27/2026		A		52,869		(3)	(3)	Common Stock, par value $0.01 per share	52,869	$0	52,869	D

Explanation of Responses:

1. On February 27, 2026, the last preceding business day, the closing price of the Company's common stock on Nasdaq was $44.63.

2. Each restricted stock unit represents a contingent right to receive one share of CoStar Group, Inc. common stock.

3. The restricted stock units vest in three equal installments on March 1, 2027, March 1, 2028 and March 1, 2029.

Remarks:

	/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 equity award did CoStar Group (CSGP) CTO Frank Simuro receive?

Frank Simuro received a grant of 52,869 restricted stock units. Each unit represents a contingent right to receive one share of CoStar Group common stock, vesting over three years starting March 1, 2027, aligning compensation with long-term company performance.

What is the vesting schedule for Frank Simuro’s new CoStar (CSGP) RSUs?

The 52,869 restricted stock units vest in three equal installments. Vesting dates are March 1, 2027, March 1, 2028, and March 1, 2029, meaning one-third of the RSUs converts into common shares on each of those dates if service conditions are met.

Why did Frank Simuro dispose of 18,702 CoStar (CSGP) shares?

The 18,702 shares were disposed of as a tax-withholding transaction, not an open-market sale. Shares were delivered to satisfy tax liabilities associated with equity compensation, using a reference price of $44.63 per share based on the prior Nasdaq closing price.

What share price was used for Frank Simuro’s CoStar (CSGP) tax withholding?

The transaction used a share price of $44.63, which was the closing price of CoStar Group’s common stock on Nasdaq on February 27, 2026, the last preceding business day, to calculate the tax-withholding share amount for the disposition.

How many CoStar (CSGP) common shares does Frank Simuro hold after these transactions?

After the tax-withholding disposition of 18,702 shares, Frank Simuro holds 425,598 CoStar Group common shares directly. This figure reflects his ownership immediately following the reported Form 4 transactions and excludes the unvested restricted stock units granted.

How many CoStar (CSGP) restricted stock units does Frank Simuro hold after the grant?

Following the reported grant, Frank Simuro holds 52,869 restricted stock units. These RSUs vest in three equal annual installments beginning March 1, 2027, potentially converting into an equal number of CoStar Group common shares if vesting conditions are satisfied.