[Form 4] Comfort Systems USA, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Comfort Systems USA, Inc. (FIX) director William J. Sandbrook reported a sale of 700 shares of the company's common stock on 08/25/2025 at an average price of $689.575 per share. After this transaction, Mr. Sandbrook directly and indirectly beneficially owns 13,166 shares, which includes 170 shares held indirectly. The Form 4 was executed by an attorney-in-fact and filed on 08/27/2025. The filing states that fuller detail on the specific prices per share is available from the company’s Office of the General Counsel.

Insights

Financial Analyst

TL;DR Insider sale of 700 shares by a director is disclosed; remaining holding remains material but no broader trading pattern is provided.

The Form 4 reports a single sale by director William J. Sandbrook of 700 shares at an average of $689.575 on 08/25/2025, leaving 13,166 shares beneficially owned. This is a routine Section 16 disclosure showing reduced insider holdings but not indicating ownership change magnitude relative to total outstanding shares. No derivative transactions or additional contemporaneous filings are reported. The filing notes additional price detail is available upon request, which limits granular analysis of execution timing and price dispersion.

Corporate Governance Expert

TL;DR Director sale reported cleanly on Form 4; documentation appears complete but offers limited context on intent or plan.

The disclosure identifies the reporting person as a director and shows a direct sale coded as an S transaction. The form is signed by an attorney-in-fact and includes an explanation about indirect ownership of 170 shares. There is no indication of Rule 10b5-1 plan notation on the face of the form. The submission meets Section 16 reporting requirements but provides minimal context about whether the sale was part of a pre-established plan or a one-off transaction.

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^*

SANDBROOK WILLIAM J

(Last) (First) (Middle)

C/O COMFORT SYSTEMS USA, INC.

675 BERING DRIVE, SUITE 400

(Street)

HOUSTON TX 77057

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
COMFORT SYSTEMS USA INC [ FIX ]

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)
08/25/2025

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	08/25/2025		S		700	D	$689.575(1)	13,166(2)	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. Represents the average price of shares sold; full information regarding the number of shares sold and specific prices will be made available upon request to the Company's Office of the General Counsel.

2. Shares held directly by the Reporting Person, including 170 shares held indirectly by the Reporting Person.

	/s/ Rachel R. Eslicker, Attorney-in-Fact	08/27/2025
	** 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 transaction did William J. Sandbrook report for FIX?

He reported a sale of 700 shares of Comfort Systems USA, Inc. common stock on 08/25/2025.

At what price were the FIX shares sold in the Form 4?

The filing reports an average price of $689.575 per share; the company can provide full price details on request.

How many FIX shares does the reporting person own after the sale?

The reporting person beneficially owns 13,166 shares following the reported transaction, including 170 shares indirectly.

Was the Form 4 properly signed and filed for FIX insider activity?

Yes. The Form 4 shows a signature by an attorney-in-fact and was dated 08/27/2025.

Does the Form 4 indicate the sale was part of a 10b5-1 plan for FIX?

No. The filing does not indicate that the transaction was made pursuant to a Rule 10b5-1 trading plan.