[Form 4] Affiliated Managers Group Insider Trading Activity

Rhea-AI Filing Summary

Churchill Dwight D., a director of Affiliated Managers Group (AMG), received 1,398 shares through vesting of previously reported awards on 08/15/2025. The transaction is recorded as an acquisition at $0 per share because the shares reflect award vesting rather than an open-market purchase. After the vesting, the reporting person beneficially owns 29,030 shares of common stock directly and holds 2,775 stock units tied to derivative awards. The filing notes these awards vest over the period 2022–2025.

Positive

• Insider ownership increased by 1,398 shares through vesting, raising direct holdings to 29,030 shares
• Awards reflect multi-year vesting (2022–2025), indicating alignment of director compensation with long-term incentives

Negative

• None.

Insights

Corporate Governance Expert

TL;DR: Director received vested awards, modestly increasing insider ownership without an open-market purchase.

The Form 4 documents routine equity compensation vesting to a director rather than a market transaction. The addition of 1,398 shares increases direct ownership to 29,030 shares and combined derivative-linked units total 2,775. This is a standard compensation vesting event disclosed under Section 16 reporting requirements and does not on its face signal a change in corporate control or strategy.

Securities Analyst

TL;DR: Transaction is non-cash vesting; limited immediate market impact but increases insider stake modestly.

The reported acquisition is coded as vesting (transaction code M) with a $0 price, indicating fulfillment of previously granted awards. The scale of the award (1,398 shares) relative to the total reported direct holdings suggests a small incremental ownership change. No sales or exercises are reported that would affect share supply or liquidity.

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
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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^*

Churchill Dwight D.

(Last) (First) (Middle)

C/O AFFILIATED MANAGERS GROUP, INC.

777 SOUTH FLAGLER DRIVE

(Street)

WEST PALM BEACH FL 33401

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
AFFILIATED MANAGERS GROUP, INC. [ AMG ]

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)
08/15/2025

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	08/15/2025		M		1,398	A	$0(1)	29,030	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
Stock Units	(1)	08/15/2025		M			1,398	(1)	(1)	Common Stock	1,398	$0	2,775	D

Explanation of Responses:

1. Reflects the vesting of previously reported awards. Awards vest 2022-2025.

	/s/ Kavita Padiyar, Attorney-in-Fact	08/18/2025
	** 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 the AMG Form 4 report for Churchill Dwight D.?

The Form 4 reports the vesting acquisition of 1,398 common shares coded as a vesting transaction (code M) on 08/15/2025.

How many AMG shares does the reporting person own after the transaction?

After the reported vesting, the reporting person beneficially owns 29,030 shares of common stock directly and holds 2,775 stock units tied to derivative awards.

Was cash involved in the reported AMG transaction?

No. The reported acquisition price is listed as $0, reflecting vesting of previously granted awards rather than a cash purchase.

What is the nature and timeframe of the vested awards?

The filing states the awards vest over the period 2022–2025 and the reported shares reflect the vesting of those previously disclosed awards.

Does the Form 4 indicate any sale or disposition of AMG shares by the reporting person?

No. The Form 4 shows an acquisition via vesting and does not report any dispositions.