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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                              --------------------
                                  SCHEDULE TO-C
                                 (RULE 14d-100)
       Tender Offer Statement Pursuant to Section 14(d)(1) or 13(e)(1) of
                       the Securities Exchange Act of 1934

                        Marsh & McLennan Companies, Inc.
                            (Name of Subject Company)

                        Marsh & McLennan Companies, Inc.
                       (Names of Filing Persons - Offeror)

           Options to Purchase Common Stock, par value $1.00 per share
                         (Title of Class of Securities)
                         ------------------------------


                 -----------------------------------------------
                                 Peter J. Beshar
                  Vice President, General Counsel and Secretary
                        Marsh & McLennan Companies, Inc.
                           1166 Avenue of the Americas
                          New York, New York 10036-2774
                                 (212) 345-5000
   (Name, Address and Telephone Number of Person Authorized to Receive Notices
                 and Communications on Behalf of Filing Persons)

                                   Copies to:
                            Richard D. Truesdell, Jr.
                              Davis Polk & Wardwell
                              450 Lexington Avenue
                            New York, New York 10017
                            Telephone: (212) 450-4000


                           CALCULATION OF FILING FEE*
        Transaction valuation                     Amount of filing fee
-------------------------------------- -----------------------------------------

*No filing fee is required because this filing contains only preliminary
communications made before the commencement of a tender offer.

|_| Check the box if any part of the fee is offset as provided by Rule
    0-11(a)(2) and identify the filing with which the offsetting fee was
    previously paid. Identify the previous filing by registration statement
    number, or the Form or Schedule and the date of its filing.

Amount Previously Paid:   ___________________  Filing Party: ___________________
Form or Registration No.: ___________________  Date Filed:   ___________________

|X| Check the box if the filing relates solely to preliminary communications
made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the
statement relates:
|_| third-party tender offer subject to Rule 14d-1.
|X| issuer tender offer subject to Rule 13e-4.
|_| going-private transaction subject to Rule 13e-3.
|_| amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results
of the tender offer: |_|
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This schedule and attached exhibits relate to a proposal to be submitted for the
approval of stockholders of Marsh & McLennan Companies, Inc. ("MMC") concerning
a stock option exchange program for certain employee optionholders.


MMC has not commenced the exchange offer referred to in the attachments or
filed the proxy statement for the 2005 Annual Meeting. When the exchange offer
is commenced, MMC will provide eligible optionholders with written materials
explaining the precise terms and timing of the exchange offer. The tender offer
materials and the proxy statement will contain important information for
optionholders and stockholders, respectively, and should be read carefully by
them prior to tendering or voting. These written materials and other documents
will be filed by MMC with the Securities and Exchange Commission and may be
obtained free of charge from the Securities and Exchange Commission's website at
www.sec.gov. If necessary, MMC stockholders may obtain a written copy of the
proxy statement and eligible MMC optionholders may obtain a written copy of the
tender offer statement, when available, by contacting MMC Corporate Development
at (212) 345-5475.


Item 12. Exhibits.

       99.1   Letter to Employees from Michael G. Cherkasky, president and chief
              executive officer of MMC, regarding approval of a stock option
              exchange program by the board of directors, subject to stockholder
              approval.

       99.2   Excerpt from scripted comments to be used by Michael G. Cherkasky,
              president and CEO of MMC, in investor conference call on Tuesday,
              March 1, 2005.





                                    SIGNATURE

       After due inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and correct.



                                        /s/ Bart Schwartz
                                        ----------------------------------------
                                        (Signature)


                                        Bart Schwartz, Deputy General Counsel
                                        ----------------------------------------
                                        (Name & Title)


                                        March 1, 2005
                                        ----------------------------------------
                                        (Date)





                                INDEX TO EXHIBITS


       99.1.  Letter to Employees (filed herewith)
       99.2   Excerpt from scripted comments (filed herewith)