8-K

                                   UNITED STATES
                        SECURITIES AND EXCHANGE COMMISSION
                              Washington, D.C. 20549

                             ________________________

                                     FORM 8-K

                                  CURRENT REPORT

                      Pursuant to Section 13 or 15(d) of the
                          Securities Exchange Act of 1934

        Date of report (Date of earliest event reported): February 28, 2005

                             ________________________

                         Marsh & McLennan Companies, Inc.
                (Exact Name of Registrant as Specified in Charter)

        Delaware                       1-5998                     36-2668272
    (State or Other           (Commission File Number)          (IRS Employer
      Jurisdiction                                           Identification No.)
   of Incorporation)

        1166 Avenue of the Americas New York, NY                    10036
        (Address of Principal Executive Offices)                  (Zip Code)

        Registrant's telephone number, including area code: (212) 345-5000

                                  Not Applicable
           (Former Name or Former Address, if Changed Since Last Report)

        Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions (see General Instruction A.2. below):

        |_|  Written communications pursuant to Rule 425 under the Securities
             Act (17 CFR 230.425)

        |_|  Soliciting material pursuant to Rule 14a-12 under the Exchange Act
             (17 CFR 240.14a-12)

        |_|  Pre-commencement communications pursuant to Rule 14d-2(b) under the
             Exchange Act (17 CFR 240.14d-2(b))

        |_|  Pre-commencement communications pursuant to Rule 13e-4(c) under the
             Exchange Act (17 CFR 240.13e-4(c))


================================================================================







                 Section 5--Corporate Governance and Management

Item 5.04. Temporary Suspension of Trading Under Registrant's Employee Benefit
Plans.

On February 28, 2005, Marsh & McLennan Companies, Inc. (the "Company") sent a
notice to its directors and executive officers informing them of a blackout
period in the Marsh & McLennan Companies Stock Investment Plan (the "SIP")
beginning on March 24, 2005, 5:00 p.m. Eastern Time, and ending during the week
of April 3, 2005 (the "Blackout Period") that will temporarily prevent
participants in the SIP from engaging in transactions in Company common stock in
their individual accounts. During the Blackout Period, participants in the SIP
generally will be unable to direct or diversify investments in their individual
accounts, change elections regarding future contributions, change contribution
rates or obtain a loan, distribution or withdrawal from the SIP. The Blackout
Period is imposed in connection with the change of the recordkeeper and trustee
for the SIP.

The Company received the notice required by Section 101(i)(2)(E) of the Employee
Retirement Income Security Act of 1974 on February 22, 2005.

Security holders or other interested persons may obtain information about the
actual beginning and ending dates of the Blackout Period, without charge, by
contacting Leon J. Lichter, Vice President, Benefits & Compensation Counsel, in
writing at Marsh & McLennan Companies, Inc., 1166 Avenue of the Americas, New
York, New York 10036, either during the Blackout Period or for a period of two
years after the ending date of the Blackout Period.

A copy of the notice transmitted to the directors and executive officers of the
Company is set forth in Exhibit 99.1 hereto and is incorporated by reference
into this Item.

                  Section 9--Financial Statements and Exhibits

Item 9.01.  Financial Statements and Exhibits.

            (c)  Exhibits

            99.1 Notice of plan blackout period to directors and executive
                 officers dated February 28, 2005.



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                                   SIGNATURES

        Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.


                                           MARSH & McLENNAN COMPANIES, INC.

                                           By: /s/ Bart Schwartz
                                           -------------------------------------
                                           Name: Bart Schwartz
                                           Title: Deputy General Counsel


Date: February 28, 2005



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EX-99

                                                                    EXHIBIT 99.1



                            NOTICE OF BLACKOUT PERIOD
                       TO DIRECTORS AND EXECUTIVE OFFICERS
                       OF MARSH & MCLENNAN COMPANIES, INC.



                     Special Trading Restrictions Related to
     the MMC Stock Investment Plan Blackout Period Beginning March 24, 2005

February 28, 2005

Background
The Marsh & McLennan Companies Stock Investment Plan (the "SIP") will be subject
to a blackout period beginning on March 24, 2005, 5:00 p.m. Eastern Time, and
ending during the week of April 3, 2005 (the "Blackout Period") that will
temporarily prevent participants in the SIP from engaging in transactions in
Marsh & McLennan Companies, Inc. ("MMC") common stock in their individual
accounts. During the Blackout Period, participants in the SIP generally will be
unable to direct or diversify investments in their individual accounts, change
elections regarding future contributions, change contribution rates or obtain a
loan, distribution or withdrawal from the SIP. The Blackout Period is necessary
to make a transition to a new recordkeeper, Mercer HR Services, and trustee,
Northern Trust Corporation.

Special Trading Restrictions
This notice is provided to you pursuant to Rule 104 of Regulation BTR
promulgated under the Securities Exchange Act of 1934 and Section 306 of the
Sarbanes-Oxley Act of 2002. Pursuant to these rules, each director and executive
officer of MMC is prohibited from, directly or indirectly, purchasing, selling
or otherwise acquiring or transferring any equity or derivative security of MMC
during the Blackout Period (the "Special Trading Restrictions"). Although the
Special Trading Restrictions are subject to certain exceptions, given the
complexity of the rules and the short time period involved, you should not
engage in any transaction in MMC common stock during the Blackout Period.
Accordingly, during the Blackout Period, you may not purchase, sell or otherwise
transfer or acquire any shares of MMC common stock or exercise any stock options
(cashless or otherwise). It is important to note that, although the Blackout
Period arises in connection with the SIP, the Special Trading Restrictions bar
directors and executive officers from trading any shares of MMC common stock
whether or not they were acquired through the SIP.

The Special Trading Restrictions are in addition to the restriction on trading
activity under MMC's insider trading policy. You should continue to direct
questions about, and requests for pre-clearance of, your transactions in MMC
common stock to Bart Schwartz, Deputy General Counsel, at (212) 345-5522.

Questions?
If you have any questions concerning the Blackout Period, including whether the
Blackout Period has ended, you should contact Leon J. Lichter, Vice President,
Benefits & Compensation





Counsel, Marsh & McLennan Companies, Inc., 1166 Avenue of the Americas, New
York, New York 10036, telephone (212) 345-9729. You will receive notice if the
Blackout Period changes for any reason.





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