Capital World Investors 5% position in Arthur J. Gallagher (NYSE: AJG)

Rhea-AI Filing Summary

Capital World Investors has filed a Schedule 13G reporting a significant ownership position in Arthur J. Gallagher & Co. common stock. It is deemed the beneficial owner of 12,951,790 shares, representing 5.0% of the 256,800,000 shares believed to be outstanding as of 12/31/2025.

The filing shows sole voting power over 12,752,906 shares and sole dispositive power over 12,951,790 shares, with no shared voting or dispositive power. The securities were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control of the company.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

Arthur J. Gallagher & Co.

(Name of Issuer)

Common Stock

(Title of Class of Securities)

363576109

(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. 363576109

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 12,752,906.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 12,951,790.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

12,951,790.00

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)

5.0 %

12

Type of Reporting Person (See Instructions)

IA

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Arthur J. Gallagher & Co.
(b)	Address of issuer's principal executive offices: 2850 Golf Road, Rolling Meadows, IL 60008-4050
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.: 363576109
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: 12,951,790 ** **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 12,951,790 shares or 5.0% of the 256,800,000 shares believed to be outstanding.
(b)	Percent of class: 5.0 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 12,752,906
	(ii) Shared power to vote or to direct the vote: 0
	(iii) Sole power to dispose or to direct the disposition of: 12,951,790
	(iv) Shared power to dispose or to direct the disposition of: 0
Item 5.	Ownership of 5 Percent or Less of a Class.
	Not Applicable
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 stake does Capital World Investors report in Arthur J. Gallagher (AJG)?

Capital World Investors reports beneficial ownership of 12,951,790 Arthur J. Gallagher shares, equal to 5.0% of the 256,800,000 shares believed outstanding. This crosses the 5% threshold that requires public disclosure on a Schedule 13G with the SEC.

Does Capital World Investors seek control of Arthur J. Gallagher (AJG)?

The filing states the shares were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control. It also notes they are not held in connection with any transaction intended to affect control, aside from specified nomination activities.

How much voting power does Capital World Investors have in AJG?

Capital World Investors reports sole voting power over 12,752,906 Arthur J. Gallagher common shares and no shared voting power. It also has sole dispositive power over 12,951,790 shares, meaning it alone can decide whether and when to sell or otherwise dispose of those shares.

When was Capital World Investors’ 5% ownership in AJG measured?

The ownership position is reported as of the event date 12/31/2025. At that time, Capital World Investors was deemed beneficial owner of 12,951,790 Arthur J. Gallagher shares, which it calculates as 5.0% of the 256,800,000 shares it believes were outstanding.

Who signed the Schedule 13G for Capital World Investors’ AJG holdings?

The Schedule 13G is signed by Timothy J. Moon, identified as Vice President and Senior Counsel of Capital Research and Management Company. The signature section certifies, after reasonable inquiry, that the information provided about the Arthur J. Gallagher shareholdings is true, complete, and correct.