Capital World Investors (FIX) discloses 4.7% Comfort Systems USA ownership in 13G/A

Rhea-AI Filing Summary

Comfort Systems USA, Inc. had a significant shareholder report a sub‑5% stake. Capital World Investors filed an amended Schedule 13G/A stating beneficial ownership of 1,640,532 shares of Comfort Systems USA common stock, representing 4.7% of the class, based on 35,271,950 shares believed to be outstanding.

The filing describes Capital World Investors as a division of several affiliated investment management entities operating under the Capital World Investors name. It also certifies that the shares were acquired and are held in the ordinary course of business, without the purpose or effect of changing or influencing control of Comfort Systems USA.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 2)

Comfort Systems USA, Inc.

(Name of Issuer)

Common Stock

(Title of Class of Securities)

199908104

(CUSIP Number)

12/31/2025

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No. 199908104

1

Names of Reporting Persons

Capital World Investors

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 1,640,532.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 1,640,532.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

1,640,532.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

4.7 %

12

Type of Reporting Person (See Instructions)

IA

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Comfort Systems USA, Inc.
(b)	Address of issuer's principal executive offices: 9753 KATY FREEWAY, SUITE 700, HOUSTON, TX 77024
Item 2.
(a)	Name of person filing: Capital World Investors
(b)	Address or principal business office or, if none, residence: 333 SOUTH HOPE STREET, 55TH FLOOR, LOS ANGELES, CALIFORNIA 90071
(c)	Citizenship: N/A
(d)	Title of class of securities: Common Stock
(e)	CUSIP No.: 199908104
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:
(k)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.	Ownership
(a)	Amount beneficially owned: 1,640,532 ** **Capital World Investors ("CWI") is a division of Capital Research and Management Company ("CRMC"), as well as its investment management subsidiaries and affiliates Capital Bank and Trust Company, Capital International, Inc., Capital International Limited, Capital International Sarl, Capital International K.K., Capital Group Private Client Services, Inc., and Capital Group Investment Management Private Limited (together with CRMC, the "investment management entities"). CWI's divisions of each of the investment management entities collectively provide investment management services under the name "Capital World Investors." CWI is deemed to be the beneficial owner of 1,640,532 shares or 4.7% of the 35,271,950 shares believed to be outstanding.
(b)	Percent of class: 4.7 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 1,640,532
	(ii) Shared power to vote or to direct the vote: 0
	(iii) Sole power to dispose or to direct the disposition of: 1,640,532
	(iv) Shared power to dispose or to direct the disposition of: 0
Item 5.	Ownership of 5 Percent or Less of a Class.
	Ownership of 5 percent or less of a class
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	Not Applicable
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	Not Applicable
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Capital World Investors

Signature:	Timothy J. Moon
Name/Title:	Vice President and Senior Counsel, Capital Research and Management Company
Date:	02/10/2026

FAQ

What percentage of Comfort Systems USA (FIX) does Capital World Investors report owning?

Capital World Investors reports beneficial ownership of 4.7% of Comfort Systems USA’s common stock. This corresponds to 1,640,532 shares, based on 35,271,950 shares of common stock believed to be outstanding, as disclosed in the Schedule 13G/A filing.

How many Comfort Systems USA (FIX) shares does Capital World Investors beneficially own?

Capital World Investors reports beneficial ownership of 1,640,532 shares of Comfort Systems USA common stock. This stake represents 4.7% of the class, calculated using 35,271,950 shares believed to be outstanding, according to the amended Schedule 13G/A disclosure.

Is Capital World Investors a passive shareholder in Comfort Systems USA (FIX)?

Yes. Capital World Investors certifies the shares were acquired and held in the ordinary course of business and not for the purpose of changing or influencing control of Comfort Systems USA, consistent with a passive institutional investor reporting under Schedule 13G/A.

What is the relationship between Capital World Investors and Capital Research and Management Company in the FIX filing?

The filing explains that Capital World Investors is a division of Capital Research and Management Company and its investment management subsidiaries and affiliates. These entities collectively provide investment management services under the Capital World Investors name and are deemed beneficial owners of the reported shares.

Where is Comfort Systems USA (FIX) headquartered, according to the Schedule 13G/A?

Comfort Systems USA’s principal executive offices are listed at 9753 Katy Freeway, Suite 700, Houston, TX 77024. This address identifies the company’s main business location in the Schedule 13G/A ownership disclosure filed by Capital World Investors.

Who signed the Capital World Investors Schedule 13G/A for Comfort Systems USA (FIX)?

The Schedule 13G/A was signed by Timothy J. Moon, who is identified as Vice President and Senior Counsel of Capital Research and Management Company. The signature certifies the accuracy and completeness of the reported beneficial ownership information.