Management Change/Compensation (Form 8-K)

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On October 1, 2026, after a distinguished career including more than 25 years at Omnicom Group Inc. (the "Company"), Andrew Castellaneta retired from his role as the Company's Senior Vice President and Chief Accounting Officer, effective immediately. Mr. Castellaneta will remain an employee of the Company for a period of time to facilitate a smooth transition. Mr. Castellaneta's retirement is not the result of any disagreement with the Company on any matter relating to the Company's operations, policies or practices.

On October 1, 2026, the Company's Board of Directors appointed Jordan Farnam as Vice President, Global Financial Reporting and Chief Accounting Officer, effective immediately.

Mr. Farnam, age 44, joined the Company in January 2024 as Vice President, Global Financial Reporting. Prior to joining the Company, he served as the Corporate Controller for Consumer Edge LLC from 2022 to 2024 and Director, Technical Accounting for Spotify USA Inc. from 2020 to 2022. Mr. Farnam previously served in various roles at PricewaterhouseCoopers LLP, including as Assurance Director, with an emphasis on serving technology and media multi-national clients in the U.S. and Finland.