What happened with the Omnicom and IPG merger?
Omnicom completed its all-stock acquisition of Interpublic Group (IPG) on 26 November 2025, after regulatory approvals, creating the world's largest advertising holding company by revenue, with pro forma revenue above $25 billion according to Omnicom. IPG shareholders received 0.344 Omnicom shares per IPG share, and the combined company trades as OMC.
The deal was announced in December 2024. It combined agency networks such as Omnicom's BBDO and OMD with IPG's McCann, UM and data business Acxiom. Legacy Omnicom shareholders own about 60.6% and IPG shareholders about 39.4%, according to the company. The US FTC's approval came with a consent order restricting the combined company from steering ad spend based on publishers' political viewpoints.
For the market, it is another sign of consolidation among holding company groups as they invest in data, retail media and AI-driven buying. Its main rivals are WPP, Publicis Groupe, Dentsu and Havas.