Omnicom Merges Mediahub and Hearts & Science

While Omnicom spent last year making itself 60% bigger, the company is currently working out how best to shrink operations. The advertising giant's takeover of Interpublic Group loaded it with staff and a surplus of agency brands and the reckoning has begun, one name at a time.

First to go are Mediahub and Hearts & Science, which Omnicom is consolidating into a single agency under a new name. It is the summer's biggest brand rationalisation, and few expect it to be the last.

"The fit between these agencies is remarkably complementary," says Florian Adamski, Global CEO of Omnicom Media Group, in an internal memo to staff and clients.

He casts Hearts & Science as the data shop, "built around data-driven marketing from day one", and Mediahub as the creative one, built on "challenger thinking, cultural creativity" and a knack for growing brands through disruption.

Rival shops, shared clients, identical decks – that is not complementary. That is Omnicom paying twice for the same pitch, and it has decided to stop.

The maths behind the merger

Omnicom has cut 7,200 positions since the end of 2025, according to Jay Pattisall, Vice-President and Senior Agency analyst at Forrester, who expects at least as many again before 2027 is out. 

The group's headcount grew 60% in the year it absorbed Interpublic, against 5.5% at Publicis Groupe and a decline of 8.7% at WPP, neither of which had bought anything on that scale. That leaves Omnicom earning less revenue per employee than its rivals, having promised Wall Street it would do the opposite.

"According to Omnicom Group's Q4 2025 investor presentation, 70% of costs savings slated for 2026 and 2027 are labor related," says Jay.

Florian's memo does not address job cuts. It sells staff "broader career paths" and clients "greater collaboration", the language of growth pinned to a plan to shrink.

Why these two agencies

Ryan Kangisser, Chief Strategy Officer at Mediasense, worries about which half of the new agency will survive the blend. Mediahub, he says, is "a creative led media buying agency, not a media led creative agency", and he is not convinced the distinction lasts.

Merging two agencies from the same side of the deal would be simplest, since they share systems, but same-side shops often share rival clients too, and advertising's oldest rule is that a Coke and a Pepsi never share a roof.

"The kind of the data and technology that Hearts & Science has, well that's just media these days, almost table stakes. I don't think that's differentiating," says Ryan.

"What is definitely differentiating in this world is that of strategy and of true creative-led media planning and buying. I don't think it's that plentiful in our marketplace."

When the Interpublic deal closed, Omnicom insisted its brands were safe. 18 months and 7,200 jobs later, two are being erased, and few in the advertising industry expect the cull to stop there.