Bryan Kennedy is stepping down as the CEO of Publicis Groupe’s Epsilon, passing responsibility to John Giuliani, who is rejoining the company as executive chairman. 

As part of the management shift, the 53-year-old Kennedy will transition into an executive strategic advisor role, effective immediately, Publicis Groupe says. Kennedy will then retire at the end of 2021.

"It’s been a privilege to work alongside our teams around the world to establish Epsilon as an industry-leader in identity, customer database and engagement, loyalty, and email," said Kennedy in a statement.

The timing comes about two years since Publicis Groupe acquired Epsilon for $4.4 billion in 2019, marking one of the largest deals in ad history. Such deals can come with earn-out periods of a few years. Publicis declined to comment on whether that is the case with Kennedy.

Arthur Sadoun, Publicis Chairman and CEO, credited Kennedy as "a key driving force behind the successful integration of Epsilon into Publicis." That has been a key to the holding company winning new business under its "Power of One" umbrella.

Last week, Publicis Groupe snagged Walmart's U.S. media account, which recorded all-in 2020 advertising spending of $2.4 billion, according to the Ad Age Datacenter. The review, which moved the business away from WPP’s Haworth after more than five years, marked the biggest holding-company pitch of the year to date.

Kennedy has led Epsilon through other notable victories, including becoming Anheuser-Busch InBev’s data agency-of-record in the U.S. and a global data partner. The brewery hired Epsilon to re-orient its media and marketing towards an audience-based approach, where customer data is used to inform the messaging approach.

In the holding company's second quarter earnings posted in July, Epsilon was cited as growing 31.1% in the second quarter.

Giuliani returns to Epsilon after serving most recently as executive chairman of Yieldify, a customer journey specialist, and as special advisor to DataPoint Capital, an internet-focused venture capital fund. Giuliani previously led and built display media company Dotomi until it was sold to Conversant in 2011, then served as CEO of Conversant until it was sold to Epsilon in December 2014. He has participated on the boards for companies including WEB.com, Q Interactive, Dotomi and Conversant.

Giuliani will work with Ric Elert, Epsilon’s current president and chief operating officer, and will report to Arthur Sadoun, CEO of Publicis Groupe. Elert’s current role will also expand to include partnerships and both vertical and international expansions at Epsilon, the company said.

"Epsilon has a set of assets that are superior in the industry and I see tremendous opportunity to continue to transform the way brands reach and engage consumers in a digital-first world," said Giuliani.