Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Ledford Laurie
2. Date of Event Requiring Statement (Month/Day/Year)
04/02/2012
3. Issuer Name and Ticker or Trading Symbol
MARSH & MCLENNAN COMPANIES, INC. [MMC]
(Last)
(First)
(Middle)
C/O MARSH & MCLENNAN COMPANIES, INC., 1166 AVENUE OF THE AMERICAS
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
SVP & Chief HR Officer
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

NEW YORK, NY 10036
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 2,981.5441
D
 
Common Stock (SIP) 561.159
D
 

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Restricted Stk. Units (SSIP)   (1)   (1) Common Stock 946.972 $ (2) D  
Restricted Stock Units   (1)   (1) Common Stock 10,177 $ (2) D  
Stock Options (Right to Buy)   (3) 03/16/2014 Common Stock 2,315 $ 27.86 D  
Stock Options (Right to Buy)   (4) 03/15/2015 Common Stock 5,000 $ 30.505 D  
Stock Options (Right to Buy)   (5) 02/11/2017 Common Stock 3,601 $ 29.6 D  
Stock Options (Right to Buy)   (6) 02/21/2020 Common Stock 30,928 $ 22.705 D  
Stock Options (Right to Buy)   (7) 02/20/2021 Common Stock 11,245 $ 30.595 D  
Stock Options (Right to Buy)   (8) 02/23/2022 Common Stock 12,418 $ 31.885 D  
Stock Options (Right to Buy) 07/01/2007 03/19/2013 Common Stock 3,000 $ 27.86 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Ledford Laurie
C/O MARSH & MCLENNAN COMPANIES, INC.
1166 AVENUE OF THE AMERICAS
NEW YORK, NY 10036
      SVP & Chief HR Officer  

Signatures

Katherine J. Brennan 04/12/2012
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(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).
(1) Not Applicable.
(2) The security converts to Marsh & McLennan Companies common stock on a 1-for-1 basis.
(3) These options were granted on July 1, 2005. 1,736 of these options vested and became exercisable on July 1, 2007. The remaining 579 of these options vested and became exercisable on March 17, 2008.
(4) These options vested in four equal annual installments on March 16th of 2006, 2007, 2008, and 2009. These options become exercisable only if, after they are vested, the closing price of Marsh & McLennan Companies common stock is at least 15% higher than the exercise price of the options for ten consecutive trading days.
(5) These options vested in four equal annual installments on February 12th of 2008, 2009, 2010, and 2011. These options become exercisable only if, after they are vested, the closing price of Marsh & McLennan Companies common stock is at least 15% higher than the exercise price of the options for ten consecutive trading days.
(6) These options were granted on February 22, 2010 and vest in four equal annual installments beginning on the first anniversary of the grant date. The first two installments vested and became exercisable on February 22, 2011 and February 22, 2012. The remaining installments vest on February 22, 2013 and February 22, 2014.
(7) These options were granted on February 21, 2011 and vest in four equal annual installments beginning on the first anniversary of the grant date. The first installment vested and became exercisable on February 21, 2012. The remaining installments vest on February 21, 2013, February 21, 2014, and February 21, 2015.
(8) These options vest in four equal annual installments on February 24, 2013, February 24, 2014, February 24, 2015, and February 24, 2016.

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