X0508 4 2024-07-29 0001004434 AFFILIATED MANAGERS GROUP, INC. AMG 0001217495 STARR LOREN M C/O AFFILIATED MANAGERS GROUP, INC. 777 SOUTH FLAGLER DRIVE WEST PALM BEACH FL 33401 1 0 Restricted Stock Units 2024-07-29 4 A 0 544 0 A Common Stock 544 544 D Deferred Stock Units 2024-07-29 4 A 0 428 0 A Common Stock 428 428 D Each restricted stock unit represents a right to receive one share of the Company's common stock upon vesting. The restricted stock units vest in full on August 15, 2025. Reflects cash fees that the director has elected to defer under the Company's deferred compensation plan, which are notionally invested in a measurement fund tracking the Company's common stock during the deferral period. Each deferred stock unit is equal to one share of the Company's common stock, and becomes distributable in common stock upon the reporting person's separation from service as a member of the Board of Directors of the Company. /s/ Kavita Padiyar, Attorney-in-Fact 2024-07-31