Omnicom Media Group

Omnicom Media Group is the media-buying arm of Omnicom Group (NYSE: OMC), formed in 2005 to coordinate the holding company’s media-services networks. It houses OMD Worldwide, PHD, Hearts & Science and the Annalect data-and-analytics subsidiary, with the proprietary Omni platform — fed by Acxiom identity and Flywheel commerce signals — operating as the cross-agency tech layer.

We track OMG because its agency networks sit on the buy side of nearly every consequential CTV, programmatic, identity and measurement-currency conversation in the industry. OMD Chief Media Officer Ben Hovaness was named buy-side co-chair of the IAB Tech Lab’s Programmatic Governance Council at the council’s April 21, 2026 launch, putting OMG’s senior media voice at the center of governance work over the $200 billion programmatic market. The unit’s scale — six agency networks and ~$73.5 billion in billings post-merger — makes its policy positions, principal-buying disclosures and tech-stack choices read as industry weather, not single-company news.

The November 2025 close of Omnicom Group’s acquisition of Interpublic Group reshaped the unit. Omnicom retired the IPG Mediabrands holding-company brand and folded UM, Initiative and Mediahub into a single Omnicom Media platform under Florian Adamski, who has been global CEO of the media division since 2021. Mediabrands now appears in our coverage as a sister media division inside the combined Omnicom holdco rather than an independent fifth Big-Four competitor — a structural shift that reframes every prior comparison of agency-network billings, principal-media exposure and walled-garden negotiating leverage.