InsiderTrades

Form 4 for AMG AFFILIATED MANAGERS GROUP, INC.

Accepted 2026-03-09 00:00:00 ET · period of report 2026-03-05 · accession 0001004434-26-000031 · SEC index · Original document

Summary rows

Aggregated the way they appear in lists: one row per insider, transaction code and security table.

X Filed Traded Ticker Insider Title Type Price Qty Owned ΔOwn Value
D 2026-03-09 2026-03-05 AMG Horgen Jay C. CEO, Dir F - Tax $299.18 -18.3K 336.9K -5% -$5.48M
D 2026-03-09 2026-03-05 AMG Horgen Jay C. CEO, Dir A - Grant $0.00 +27.3K 355.2K +8% $0
D 2026-03-09 2026-03-05 AMG Horgen Jay C. CEO, Dir M - OptEx $0.00 +17.6K 327.9K +6% $0
D 2026-03-09 2026-03-05 AMG Horgen Jay C. CEO, Dir M - OptEx $0.00 -17.6K 22.9K -43% $0
D 2026-03-09 2026-03-05 AMG Horgen Jay C. CEO, Dir A - Grant $0.00 +8,544 8,544 New $0

Purchase Sale Sale after option exercise All abbreviations

Every reported transaction

#TableSecurityDateCodeA/DSharesPriceOwned afterOwnExercise / expiryUnderlyingFootnotes
1 Common Common Stock 2026-03-05 F D 18,333 $299.18 336,877 D — — (F4) Reflects the automatic surrender of shares of common stock to the Company to satisfy tax withholding obligations related to the vesting of the awards described above.
2 Common Common Stock 2026-03-05 A A 27,260 $0.00 355,210 D — — (F3) Award granted in March 2023, which settled following the achievement of performance conditions previously described in the Company's annual meeting proxy statements.
3 Common Common Stock 2026-03-05 M A 17,563 $0.00 327,950 D — — (F1) Reflects the vesting of previously reported awards. Awards vest 2023-2029. (F2) Reflects the transfer of 200,000 shares of common stock to a grantor retained annuity trust.
4 Derivative Stock Units 2026-03-05 M D 17,563 $0.00 22,891 D — · — to — 17,563 Common Stock (F1) Reflects the vesting of previously reported awards. Awards vest 2023-2029.
5 Derivative Stock Units 2026-03-05 A A 8,544 $0.00 8,544 D — · — to — 8,544 Common Stock (F5) The award, issued under the Company's 2020 Equity Incentive Plan, vests in four equal installments on each of March 5, 2027, 2028, 2029, and 2030.