144 0001871327 XXXXXXXX LIVE 0000062709 MARSH & MCLENNAN COMPANIES, INC. 001-05998 1166 AVENUE OF THE AMERICAS NEW YORK NY 10036 2123455000 Studer Nicholas Mark Officer Common Fidelity Brokerage Services LLC

900 Salem Street Smithfield RI 02917

49390 11366732.27 491131126 03/12/2025 NYSE Common 03/12/2025 Option Granted 02/22/2016 Issuer N 5667 03/12/2025 Cash Common 03/12/2025 Option Granted 02/22/2017 Issuer N 6490 03/12/2025 Cash Common 03/12/2025 Option Granted 02/21/2018 Issuer N 4070 03/12/2025 Cash Common 03/12/2025 Option Granted 02/19/2019 Issuer N 3049 03/12/2025 Cash Common 03/12/2025 Option Granted 02/19/2020 Issuer N 3881 03/12/2025 Cash Common 03/12/2025 Option Granted 02/22/2021 Issuer N 3163 03/12/2025 Cash Common 03/12/2025 Option Granted 02/23/2022 Issuer N 11739 03/12/2025 Cash Common 03/12/2025 Option Granted 02/23/2023 Issuer N 7587 03/12/2025 Cash Common 03/12/2025 Option Granted 02/22/2024 Issuer N 3744 03/12/2025 Cash N Nicholas Studer

1166 Avenue of the Americas New York, NY 10036-2774

Common 03/03/2025 3649 871152.41 03/12/2025 /s/ Daniel Tucci, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Nicholas Studer