The merger between major holding companies Omnicom Group and Interpublic Group (IPG) continues to shake up leadership ranks. Eileen Kiernan, the chief executive of IPG’s media division, IPG Mediabrands, will step down from her role as the firm is absorbed into the new company, according to an internal memo reviewed by ADWEEK.
Kiernan’s announcement is part of the ongoing ripple effects from Omnicom’s $13 billion acquisition of IPG, finalized last week, which has already seen thousands of jobs axed, the shuttering of three historic ad agencies, and a major executive reshuffling. As part of the merger, IPG Mediabrands will be folded into the combined company’s new media division, Omnicom Media.
![Since Omnicom announced its intent to acquire Interpublic Group (IPG) in December of last year, industry onlookers have speculated what the new company will look like. Among the key questions: […]](https://static-www.adweek.com/wp-content/uploads/2025/11/omnicom-ipg-merger-takeaways-2025.jpg?w=640&h=360&crop=1)
“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 in the memo, which was sent to staff on Monday. “I want to thank all for your dedicated service, unwavering commitment, partnership, and friendship, particularly over these past three years. We’ve been fortunate to have had this time together, and we wish you all good things in the chapter ahead.”
She continued: “As for me, after an incredible 14 years with IPG, I too will be moving on to embrace my next adventure—full of family and friends. My departure won’t be immediate, however. I’ll be staying on through the first few months of 2026, helping Flo [Omnicom Media CEO Florian Adamski] with the transition to ensure a smooth landing for you and our clients into the new Omnicom.”
Kiernan took the top post at IPG Mediabrands in 2023 after a nearly five-year stint as global president for the agency network’s Johnson & Johnson account.
In her email Monday, she added that “[m]ore changes will be announced in the coming days,” but underscored the company’s ongoing “commitment to excellence in client partnership, our continued investment in an unparalleled suite of connected capabilities, and our commitment to a powerful, unifying operating model.”
