[SCHEDULE 13G/A] Aecom SEC Filing

Rhea-AI Filing Summary

Primecap Management Co. reports beneficial ownership of 9,580,852 common shares of AECOM, representing 7.24% of the class. The filing shows Primecap has sole voting power over 9,256,652 shares and sole dispositive power over 9,580,852 shares, indicating direct control of voting and disposition for the vast majority of its stake.

Primecap is identified as an investment adviser (IA) and certifies the shares were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control of AECOM. The statement is a Schedule 13G/A disclosure of a material passive stake above the 5% threshold.

Positive

• Material institutional stake: Primecap beneficially owns 9,580,852 shares (7.24%), exceeding the 5% reporting threshold
• Sole voting/dispositive power: Primecap reports sole voting power over 9,256,652 shares and sole dispositive power over 9,580,852 shares

Negative

• None.

Insights

Financial Analyst

TL;DR Primecap holds a material passive position in AECOM — 7.24% ownership with sole voting/dispositive power on most shares.

Primecap's 9.58 million-share position is large enough to be material to equity ownership metrics and will appear in institutional ownership tables. Because the filing is a Schedule 13G/A and the filer certifies a passive intent, this is not a control or activist signal. For analysts, the key takeaway is that a prominent investment adviser has a meaningful stake without asserting control, which can influence liquidity and ownership concentration metrics but is unlikely to drive governance changes absent further disclosures.

Corporate Governance Expert

TL;DR AECOM now has a significant single institutional holder (7.24%); Primecap reports passive intent and sole voting/dispositive authority over most shares.

From a governance perspective, the filing documents a concentrated institutional position with sole voting authority on 9.26 million shares. The certification that holdings are not intended to influence control reduces immediate takeover or proxy contest concerns. However, any future shift from a Schedule 13G to a Schedule 13D or additional disclosures would be material. Current disclosure is routine but important for board-monitoring and ownership analysis.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 10)

AECOM

(Name of Issuer)

COM

(Title of Class of Securities)

00766T100

(CUSIP Number)

06/30/2025

(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. 00766T100

1

Names of Reporting Persons

PRIMECAP MANAGEMENT CO/CA/

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

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 9,256,652.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 9,580,852.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

9,580,852.00

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)

7.24 %

12

Type of Reporting Person (See Instructions)

IA

SCHEDULE 13G

Item 1.
(a)	Name of issuer: AECOM
(b)	Address of issuer's principal executive offices: 13355 Noel Road, Suite 400, Dallas, TEXAS 75240
Item 2.
(a)	Name of person filing: PRIMECAP MANAGEMENT CO/CA/
(b)	Address or principal business office or, if none, residence: 177 EAST COLORADO BLVD. 11TH FLOOR PASADENA, California 91105
(c)	Citizenship: PRIMECAP MANAGEMENT CO/CA/ - UNITED STATES
(d)	Title of class of securities: COM
(e)	CUSIP No.: 00766T100
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: 9,580,852
(b)	Percent of class: 7.24 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: PRIMECAP MANAGEMENT CO/CA/ - 9,256,652
	(ii) Shared power to vote or to direct the vote: PRIMECAP MANAGEMENT CO/CA/ - 0
	(iii) Sole power to dispose or to direct the disposition of: PRIMECAP MANAGEMENT CO/CA/ - 9,580,852
	(iv) Shared power to dispose or to direct the disposition of: PRIMECAP MANAGEMENT CO/CA/ - 0
Item 5.	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.

PRIMECAP MANAGEMENT CO/CA/

Signature:	Jorge A. Rodriguez
Name/Title:	Deputy Chief Compliance Officer
Date:	08/13/2025

FAQ

How many AECOM (ACM) shares does Primecap report owning?

Primecap reports beneficial ownership of 9,580,852 shares of AECOM common stock.

What percentage of AECOM does Primecap own according to the filing?

The filing states Primecap owns 7.24% of the class.

Does Primecap have voting or dispositive power over the AECOM shares?

Yes. The filing shows sole voting power for 9,256,652 shares and sole dispositive power for 9,580,852 shares.

Is Primecap acting as an activist or seeking control of AECOM?

No. Item 10 certifies 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 issuer.

What type of filer is Primecap listed as on the Schedule?

Primecap is identified as an Investment Adviser (IA) on the filing.