Eileen Kiernan to exits as IPG mediabrands CEO amid Omnicom-IPG merger shake-up

New Delhi: The leadership reshuffle triggered by Omnicom Group’s $13-billion acquisition of Interpublic Group (IPG) continues to gather pace, with Eileen Kiernan, Global Chief Executive Officer of IPG Mediabrands, announcing her exit as the media network is folded into the newly created Omnicom Media division.

Kiernan confirmed her departure in an internal email to staff, noting that the consolidation of IPG’s media operations into Omnicom Media brings with it structural changes and leadership transitions.

The merged media unit will be led by Florian Adamski, formerly CEO of Omnicom Media Group, who now oversees the expanded portfolio under the simplified “Omnicom Media” identity.

“As IPG Mediabrands evolves into the next chapter of Omnicom Media, regrettably we will be saying goodbye to a number of our people, including some of our global leaders,” Kiernan wrote, acknowledging the layoffs already underway since the merger was finalised last week. The deal has already resulted in thousands of job cuts, the closure of three storied agencies, and the reorganisation of major business units across both holding groups.

Kiernan, who has been with IPG for 14 years and took over as global CEO of Mediabrands in 2023, said she would stay on through the first few months of 2026 to support Adamski in ensuring “a smooth landing” for teams and clients. “After an incredible 14 years with IPG, I too will be moving on to embrace my next adventure, full of family and friends,” she told employees.

Her note stressed that despite the upheaval, the combined organisation will continue to invest in connected capabilities and maintain a unified operating model. She added that the “transformational work” done across disciplines at Mediabrands would not be discarded but would instead be strengthened under Omnicom’s umbrella.

Kiernan closed her note on an emotional and optimistic note: “It has been the honour of my lifetime to travel alongside you these past three-plus years. Stay focused, keep shining. I’ll be cheering you on, loudly and proudly.”

As part of the merged structure, Omnicom Media will house six major media agencies: OMD, Hearts & Science and PHD from Omnicom, and UM, Initiative and Mediahub from IPG. 

Commercial delivery will be driven by Omnicom Media Investment, Outdoor Media Group, and Kinesso, while both Acxiom and Annalect will fall under the new division. Specialist units such as Optimum Sports, Fuse, Ptarmigan, TRKKN and influencer shop Creo will also report into the consolidated media organisation.

While the top leadership will largely come from the former Omnicom Media Group, several senior IPG Mediabrands executives, including Justin Wroe (chief commercial officer), Daniel Fox (chief investment officer) and Jonathan Rigby (chief strategy officer), will transition into similar roles within Omnicom Media.

With Omnicom expected to significantly expand its principal media trading operations post-merger, analysts have noted that the consolidation could reshape the flow of billions in global ad dollars and tighten the holding company’s grip on media buying.