UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C.  20549

_____________________

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 14(d) of the

Securities Exchange Act of 1934

Date of report (Date of earliest event reported) May 10, 2013

Marsh & McLennan Companies, Inc.

(Exact Name of Registrant as Specified in Charter)

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

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

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:

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

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

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

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

Item 8.01        Other Events

As previously announced by Marsh & McLennan Companies, Inc. (the "Company"), effective January 1, 2013, the Corporate Benefits and Association businesses, which were previously part of Marsh's US Consumer operations in the Risk and Insurance Services segment, were transferred to Mercer. Accordingly, these businesses are now part of the Consulting segment. In addition, also effective January 1, 2013, Mercer realigned management responsibility for its Outsourcing business within its other lines of business, which did not impact total segment results.

In order to reflect these reclassifications, the Company has attached hereto as Exhibits 99.1 and 99.2, respectively, amended presentations of the following sections of its Annual Report on Form 10-K for the fiscal year ended December 31, 2012. There were no other changes made to the originally filed document:

• Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations; and

• Item 8. Financial Statements and Supplementary Data (including segment data and related disclosures contained in the Company’s audited consolidated financial statements for each of the three years in the period ended December 31, 2012).

Item 9.01        Financial Statements and Exhibits

(d)        Exhibits

Exhibit No.	Exhibit Name
23.1	Consent of Deloitte & Touche LLP
99.1	Amended Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations of the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2012
99.2	Amended Item 8. Financial Statements and Supplementary Data of the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2012
101.INS	XBRL Instance Document
101.SCH	XBRL Taxonomy Extension Schema
101.CAL	XBRL Taxonomy Extension Calculation Linkbase
101.DEF	XBRL Taxonomy Extension Definition Linkbase
101.LAB	XBRL Taxonomy Extension Label Linkbase
101.PRE	XBRL Taxonomy Extension Presentation Linkbase

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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/ Luciana Fato
Name:	Luciana Fato
Title:	Deputy General Counsel &
	Corporate Secretary

Date:     May 10, 2013

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EXHIBIT INDEX

Exhibit No.	Exhibit Name
23.1	Consent of Deloitte & Touche LLP
99.1	Amended Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations of the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2012
99.2	Amended Item 8. Financial Statements and Supplementary Data of the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2012
101.INS	XBRL Instance Document
101.SCH	XBRL Taxonomy Extension Schema
101.CAL	XBRL Taxonomy Extension Calculation Linkbase
101.DEF	XBRL Taxonomy Extension Definition Linkbase
101.LAB	XBRL Taxonomy Extension Label Linkbase
101.PRE	XBRL Taxonomy Extension Presentation Linkbase

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INFORMATION CONCERNING FORWARD-LOOKING STATEMENTS

This Current Report on Form 8-K contains “forward-looking statements,” as defined in the Private Securities Litigation Reform Act of 1995. These statements, which express management's current views concerning future events or results, use words like “anticipate,” “assume,” “believe,” “continue,” “estimate,” “expect,” “future,” “intend,” “plan,” “project” and similar terms, and future or conditional tense verbs like “could,” “may,” “might,” “should,” “will” and “would.” For example, we may use forward-looking statements when addressing topics such as: the outcome of contingencies; the expected impact of acquisitions and dispositions; pension obligations; market and industry conditions; the impact of foreign currency exchange rates; our effective tax rates; the impact of competition; changes in our business strategies and methods of generating revenue; the development and performance of our services and products; changes in the composition or level of our revenues; our cost structure, dividend policy, cash flow and liquidity; future actions by regulators; and the impact of changes in accounting rules.

Forward-looking statements are subject to inherent risks and uncertainties. Factors that could cause actual results to differ materially from those expressed or implied in our forward-looking statements include, among other things:

• our exposure to potential liabilities arising from errors and omissions claims against us, particularly in our Marsh and Mercer businesses;

• our ability to make strategic acquisitions and dispositions and to integrate, and realize expected synergies, savings or strategic benefits from the businesses we acquire;

• the impact of any regional, national or global political, economic, regulatory or market conditions on our results of operations and financial condition;

• changes in the funded status of our global defined benefit pension plans and the impact of any increased pension funding resulting from those changes;

• the impact of competition, including with respect to our geographic reach, the sophistication and quality of our services, our pricing relative to competitors, our customers' option to self-insure or utilize internal resources instead of consultants, and our corporate tax rates relative to a number of our competitors;

• the extent to which we retain existing clients and attract new business, and our ability to incentivize and retain key employees;

• our exposure to potential criminal sanctions or civil remedies if we fail to comply with foreign and U.S. laws and regulations that are applicable to our international operations, including trade sanctions laws such as the Iran Threat Reduction and Syria Human Rights Act of 2012, anti-corruption laws such as the U.S. Foreign Corrupt Practices Act and the U.K. Bribery Act 2010, local laws prohibiting corrupt payments to government officials, as well as import and export restrictions;

• our ability to maintain adequate physical, technical and administrative safeguards to protect the security of data;

• the impact of changes in interest rates and deterioration of counterparty credit quality on our results related to our cash balances and investment portfolios, including corporate and fiduciary funds;

• the impact on our net income or cash flows and our effective tax rate in a particular period caused by settled tax audits and expired statutes of limitation;

• the impact on our net income caused by fluctuations in foreign currency exchange rates;

• the potential impact of rating agency actions on our cost of financing and ability to borrow, as well as on our operating costs and competitive position;

• our ability to successfully recover should we experience a disaster or other business continuity problem;

• changes in applicable tax or accounting requirements; and

• potential income statement effects from the application of FASB's ASC Topic No. 740 (“Income Taxes”) regarding accounting treatment of uncertain tax benefits and valuation allowances, including the effect of any subsequent adjustments to the estimates we use in applying this accounting standard.

The factors identified above are not exhaustive. Marsh & McLennan Companies and its subsidiaries operate in a dynamic business environment in which new risks may emerge frequently. Accordingly, we caution readers not to place undue reliance on the above forward-looking statements, which speak only as of the dates on which they are made. The Company undertakes no obligation to update or revise any forward-looking statement to reflect events or circumstances arising after the date on which it is made. Further information concerning the Company and its businesses, including information about factors that could materially affect our results of operations and financial condition, is contained in the Company's filings with the Securities and Exchange Commission, including the “Risk Factors” section of our most recently filed Annual Report on Form 10-K.

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