Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN 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 *
Nadler David A
  2. Issuer Name and Ticker or Trading Symbol
MARSH & MCLENNAN COMPANIES, INC. [MMC]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Vice Chairman, Office of CEO
(Last)
(First)
(Middle)
1166 AVENUE OF THE AMERICAS
3. Date of Earliest Transaction (Month/Day/Year)
09/25/2012
(Street)

NEW YORK, NY 10036
4. If Amendment, Date Original Filed(Month/Day/Year)
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 Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 09/25/2012   M   3,691 A $ 34.2211 109,995.4722 (1) D  
Common Stock 09/25/2012   S   3,691 D $ 34.2211 106,304.4722 D  
Common Stock 09/25/2012   M   11,071 A $ 34.2211 117,375.4722 D  
Common Stock 09/25/2012   S   11,071 D $ 34.2211 106,304.4722 D  
Common Stock 09/25/2012   M   35,000 A $ 34.2211 141,304.4722 D  
Common Stock 09/25/2012   S   35,000 D $ 34.2211 106,304.4722 D  
Common Stock 09/25/2012   M   94,697 A $ 34.2211 201,001.4722 D  
Common Stock 09/25/2012   S   94,697 D $ 34.2211 106,304.4722 D  
Common Stock 09/25/2012   M   122,550 A $ 34.2211 228,854.4722 D  
Common Stock 09/25/2012   S   122,550 D $ 34.2211 106,304.4722 D  
Common Stock 09/25/2012   M   425 A $ 34.2211 106,729.4722 D  
Common Stock 09/25/2012   S   425 D $ 34.2211 106,304.4722 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Stock Options (Right to Buy) $ 27.86 09/25/2012   M     3,691 03/17/2008 03/16/2014 Common Stock 3,691 $ 0 0 D  
Stock Options (Right to Buy) $ 27.86 09/25/2012   M     11,071 07/01/2007 03/16/2014 Common Stock 11,071 $ 0 0 D  
Stock Options (Right to Buy) $ 27.86 09/25/2012   M     35,000 07/01/2007 03/19/2013 Common Stock 35,000 $ 0 0 D  
Stock Options (Right to Buy) $ 26.07 09/25/2012   M     94,697   (2) 02/25/2018 Common Stock 94,697 $ 0 0 D  
Stock Options (Right to Buy) $ 19.045 09/25/2012   M     122,550   (3) 02/22/2019 Common Stock 122,550 $ 0 40,849 D  
Stock Options (Right to Buy) $ 22.705 09/25/2012   M     425   (4) 02/21/2020 Common Stock 425 $ 0 192,874 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Nadler David A
1166 AVENUE OF THE AMERICAS
NEW YORK, NY 10036
      Vice Chairman, Office of CEO  

Signatures

 /s/ Lucy Fato, Attorney-in-Fact   09/27/2012
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(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) Includes dividend reinvestment shares acquired on May 15, 2012 and August 15, 2012.
(2) These options were granted on February 26, 2008 and vested in four equal installments on February 26th of 2009, 2010, 2011 and 2012. These options become exercisable only if, after they are vested, the price of Marsh & McLennan Companies common stock is at least 15% higher than the exercise price of the options for ten consecutive trading days.
(3) These options were granted on February 23, 2009 and vest in four equal annual installments beginning on the first anniversary of the grant date. The first three installments vested and became exercisable on February 23, 2010, February 23, 2011 and February 23, 2012. The remaining installment vests on February 23, 2013.
(4) 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 second two installments vest on February 22, 2013 and February 22, 2014.

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