Director Cates G. Staley buys AMG (NYSE: AMG) stock in open market

Rhea-AI Filing Summary

AFFILIATED MANAGERS GROUP, INC. director Cates G. Staley reported an open-market purchase of Common Stock. Staley bought 1,500 shares at a price of $305.83 per share and now directly holds 6,405 shares following this transaction.

Insider Trade Summary

Net Buyer: 1,500 shares ($458,745)

Net Buy 1 txn

Insider Cates G. Staley

Role null

Bought 1,500 shs ($459K)

Type	Security	Shares	Price	Value
Purchase	Common Stock	1,500	$305.83	$459K

Holdings After Transaction: Common Stock — 6,405 shares (Direct, null)

Footnotes (1)

Key Figures

Shares purchased: 1,500 shares Purchase price: $305.83 per share Shares after transaction: 6,405 shares +1 more

4 metrics

Shares purchased 1,500 shares Open-market purchase of Common Stock

Purchase price $305.83 per share Reported transaction price

Shares after transaction 6,405 shares Total direct holdings following purchase

Net buy shares 1,500 shares Net share change from this Form 4

Key Terms

open-market purchase, Common Stock, Form 4, non-derivative

4 terms

open-market purchase financial

"transaction_action": "open-market purchase""

An open-market purchase is when an investor or a company buys shares on a public stock exchange at the going market price, rather than through a private deal. It matters to investors because these purchases change how many shares are available, can push the stock price up or signal confidence from large buyers, and often affect per-share metrics like earnings—think of it like someone buying lots of apples off a grocery shelf, reducing supply and potentially raising the price.

Common Stock financial

""security_title": "Common Stock""

Common stock represents ownership shares in a company, giving investors a stake in its success and a say in important decisions through voting rights. It is the most common type of stock traded on markets and can provide income through dividends, as well as potential for value growth. For investors, holding common stock means sharing in the company’s profits and risks.

Form 4 regulatory

"INSIDER FILING DATA (Form 4)"

Form 4 is a official document that company insiders, such as executives or major shareholders, file with regulators whenever they buy or sell company shares. It provides transparency about how those with inside knowledge are trading, helping investors see if insiders are confident in the company's prospects or may be selling for personal reasons. This information can influence investor decisions by revealing insiders' perspectives on the company's value.

non-derivative financial

""transaction_type": "non-derivative""

Form 4 Insider Transactions: What Each Field Means →

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^*

Cates G. Staley

(Last) (First) (Middle)

C/O AFFILIATED MANAGERS GROUP, INC.

1001 U.S. HIGHWAY ONE NORTH

(Street)

JUPITER FLORIDA 33477

(City) (State) (Zip)

UNITED STATES

(Country)

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)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/06/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

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	05/06/2026		P		1,500	A	$305.83	6,405	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:

	/s/ Kavita Padiyar, Attorney-in-Fact	05/06/2026
	** 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.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transaction did AMG director Cates G. Staley report?

Cates G. Staley reported an open-market purchase of AMG stock. The Form 4 shows Staley bought Common Stock in an open-market transaction, increasing direct ownership and disclosing the trade to the market in line with SEC reporting requirements.

How many AMG shares did Cates G. Staley buy in this Form 4 filing?

Staley bought 1,500 shares of AMG Common Stock. The transaction was reported as a non-derivative open-market purchase, which directly increased the director’s shareholding position in the company’s common equity.

At what price were the AMG shares purchased by Cates G. Staley?

The 1,500 AMG shares were purchased at $305.83 per share. This reported transaction price reflects the cost per share in the open-market trade disclosed in the Form 4 filing.

What is Cates G. Staley’s AMG shareholding after this transaction?

Staley directly holds 6,405 AMG shares after the purchase. The Form 4 specifies that total shares following the transaction increased to 6,405, reflecting the new ownership level in the company’s Common Stock.

Was the AMG insider transaction a buy or a sell?

The AMG insider transaction was a buy. The Form 4 uses transaction code “P” and describes the action as an open-market purchase, indicating shares were acquired rather than sold in this reported trade.