X0303 4 2011-02-15 0000062709 MARSH & MCLENNAN COMPANIES, INC. MMC 0001197664 BURNS M MICHELE 1166 AVENUE OF THE AMERICAS NEW YORK NY 10036 1 Chairman & CEO, Mercer Common Stock 2011-02-15 4 M 0 15724 0 A 47059 D Common Stock 2011-02-15 4 F 0 5103 28.805 D 41956 D Restricted Stock Units 2011-02-15 4 M 0 15724 0 D Common Stock 15724 76352 D Vesting and distribution to reporting person of 15,724 shares underlying restricted stock units of which 5,103 shares were withheld by Marsh & McLennan Companies to cover applicable taxes. These 15,724 shares underlying restricted stock units relate to 8,751 restricted stock units that were granted on February 23, 2009 and 6,973 restricted stock units that were granted on February 22, 2010. The security converts to Marsh & McLennan Companies common stock on a 1-for-1 basis. Not Applicable. /s/ Lucy Fato, Attorney-in-Fact 2011-02-17