Results of Operations

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) October 19, 2023 Marsh & McLennan Companies, Inc. (Exact Name of Registrant as Specified in its 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:   ☐ 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))     Securities registered pursuant to Section 12(b) of the Act: Title of each class Trading symbol(s) Name of exchange on which registered Common Stock, par value $1.00 per share MMC New York Stock Exchange Chicago Stock Exchange London Stock Exchange     Indicate by check mark whether the registrant is an emerging growth company as defined in as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.   ☐ Item 2.02        Results of Operations and Financial Condition       On October 19, 2023 , Marsh & McLennan Companies, Inc. issued a press release reporting financial results for the third quarter ended September 30, 2023, and announcing that a conference call to discuss such results will be held at 8:30 a.m. Eastern time on October 19, 2023. A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference. For purposes of Section 18 of the Securities Exchange Act of 1934, the press release is deemed furnished not filed.   Item 9.01        Financial Statements and Exhibits   (d)        Exhibits   99.1      Press release issued by Marsh & McLennan Companies, Inc. on October 19, 2023.     2 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/ Connor Kuratek   Name: Connor Kuratek   Title: Deputy General Counsel & Corporate Secretary         Date:    October 19, 2023 3 EXHIBIT INDEX     Exhibit No.             Exhibit   99.1 Press release issued by Marsh & McLennan Companies, Inc. on October 19, 2023. 4