CoStar Group (CSGP) CEO receives 83,708 RSUs, disposes 59,593 shares for taxes

Rhea-AI Filing Summary

CoStar Group President and CEO Andrew C. Florance reported a mix of equity compensation events. He received a grant of 83,708 restricted stock units on February 27, 2026, each representing a contingent right to one share of CoStar Group common stock. These units vest in three equal installments on March 1, 2027, March 1, 2028, and March 1, 2029.

On March 1, 2026, 59,593 shares of common stock were disposed of at $44.63 per share in a tax-withholding transaction to cover obligations associated with equity awards. After this disposition, he directly owned 1,527,273.03 shares of common stock, in addition to the 83,708 restricted stock units.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider FLORANCE ANDREW C

Role President and CEO

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock, par value $0.01 per share	59,593	$44.63	$2.66M
Grant/Award	Restricted Stock Units	83,708	$0.00	--

Holdings After Transaction: Common Stock, par value $0.01 per share — 1,527,273.03 shares (Direct); Restricted Stock Units — 83,708 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^*

FLORANCE ANDREW 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
X	Officer (give title below)		Other (specify below)
	President and CEO

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		59,593	D	$44.63(1)	1,527,273.03	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		83,708		(3)	(3)	Common Stock, par value $0.01 per share	83,708	$0	83,708	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 insider transactions did CoStar (CSGP) CEO Andrew Florance report?

Andrew Florance reported both an equity grant and a tax-related share disposition. He received 83,708 restricted stock units and disposed of 59,593 common shares in a tax-withholding transaction at $44.63 per share.

How many restricted stock units did CoStar (CSGP) grant to its CEO?

CoStar granted Andrew Florance 83,708 restricted stock units. Each unit represents a contingent right to receive one share of common stock, vesting in three equal installments across 2027, 2028, and 2029, subject to the stated vesting dates.

When do Andrew Florance’s CoStar (CSGP) restricted stock units vest?

The 83,708 restricted stock units vest in three equal annual installments. The vesting dates are March 1, 2027, March 1, 2028, and March 1, 2029, aligning the CEO’s compensation with longer-term company performance.

Why did CoStar (CSGP) CEO dispose of 59,593 shares on March 1, 2026?

The 59,593 shares were disposed of to cover tax obligations. The transaction was coded as a tax-withholding disposition at $44.63 per share, meaning shares were delivered to satisfy tax liabilities rather than sold in an open-market trade.

How many CoStar (CSGP) shares does Andrew Florance own after these transactions?

After the March 1, 2026 tax-withholding disposition, Andrew Florance directly owned 1,527,273.03 common shares. He also held 83,708 restricted stock units that may convert into additional shares as they vest over three years.

What price reference is disclosed for CoStar (CSGP) common stock in this filing?

The filing notes a closing price of $44.63 for CoStar’s common stock on February 27, 2026. That Nasdaq closing price also matches the per-share value used for the 59,593-share tax-withholding disposition on March 1, 2026.