UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE QUARTERLY PERIOD ENDED MARCH 31, 2023 ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission File Number: 1-10551 OMNICOM GROUP INC. (Exact name of registrant as specified in its charter) New York 13-1514814 (State or other jurisdiction of incorporation or organization) (IRS Employer ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE FISCAL YEAR ENDED DECEMBER 31, 2022 Commission File Number: 1-10551 OMNICOM GROUP INC. (Exact name of registrant as specified in its charter) New York 13-1514814 (State or other jurisdiction of (I.R.S. Employer Identification No.) incorporation or organization) 280 Park Avenue, New York, NY 10017 (Address of principal executive offic ...