The Omnicom–IPG mega merger changes everything, especially for CMOs

Omnicom has completed its US$13.3 billion takeover of Interpublic, forming the world’s largest advertising holding company with more than US$20 billion in revenue and roughly 100,000 staff worldwide.

The deal unites two of the industry’s biggest holding companies under the Omnicom umbrella. John Wren remains chairman and CEO, with Phil Angelastro staying on as EVP and CFO. The full leadership slate will be announced on 1 December.

Wren described the move as a “defining moment” for the advertising industry. “Omnicom is setting a new standard for modern marketing and sales leadership – creating stronger brands, delivering superior business outcomes, and driving sustainable growth.”

The ripple effects for CMOs will be immediate. In practice, brand marketers are about to deal with a mega-network that controls a vast swathe of media, data, CRM and creative assets under one roof – at exactly the moment AI is rewiring how those disciplines connect.

SEE MORE: Omnicom seals Interpublic takeover, structural details to be revealed next week

Wren is clear about the ambition. He has described the deal as a way to create the world’s leading marketing and sales business, promising a platform that accelerates growth through “strategic advantages" in data, media, creativity, production and technology.

The integration framework already points to heavy rationalisation. If the rumour mill is right, some 127 companies will be consolidated to 30. Incredible.

How that consolidation will play out is anyone's guess. Speculation has it that creative will be focused around BBDO, McCann and TBWA. Overlapping networks and regional brands will be folded in or retired.

Severance costs at Omnicom have more than doubled this year – a probable sign the reshaping is well under way.

For marketers, this cuts both ways. On one hand, there is the promise of cleaner access to data, media and production at scale. On the other, there is a real risk that cherished agency relationships are destabilised as local teams are absorbed, merged or rebranded. DDB’s rumoured retirement is a warning shot. If an icon built on “Think Small” can be sacrificed to the spreadsheet, nothing is sacred.

Why WPP’s move matters just as much

If Omnicom–IPG is the scale play, WPP is the transformation play. Cindy Rose stepped into the chief executive role with a CV built almost entirely in technology and enterprise change – Microsoft, Vodafone, Disney – and six years on WPP’s board advising on digital strategy.

She inherited a group squeezed by falling revenue, restless investors and intensifying competition from both networks and consultancies. Shares have been languishing at 16-year lows. Sir Martin Sorrell told MARKETING-INTERACTIVE “the jury is out,” warning WPP needs a “laser-like, 24/7 focus” on US clients and talent.

SEE MORE: How Cindy Rose will transform WPP

Rose’s early moves suggest she is not interested in incrementalism. Devika Bulchandani shifts from running Ogilvy to WPP chief operating officer. Laurent Ezekiel takes over Ogilvy Group, bringing his Open X experience from the Coca-Cola account. Floriane Tripolino steps up to lead WPP Open X, with a mandate to scale data and AI-led models across Coca-Cola and Nestlé.

This is not just musical chairs. It is a clear attempt to pivot WPP from a loose federation of agencies into a more integrated, product-like platform where AI, data and global delivery sit at the centre. As one senior observer put it, transformation in a business “delivered by charging human hours” will require courage and charisma. Rose’s bet is that tech discipline and platform thinking can be imposed on a model built for analogue media.

In a world where Omnicom–IPG is chasing maximum scale and WPP is trying to reframe itself as a tech platform, what we saw from Havas group across Australia and New Zealand this week follows a smaller, but strategically similar shift. The group is leaning hard into a narrative that it can move faster, integrate media, creative and data more tightly, and avoid the bureaucracy that dogs larger rivals.

The AI undertow

Across all of this the common undertow is AI. Scale now matters less for buying a marginally cheaper TV spot and more for training models, building proprietary tools, owning data clean rooms and stitching together always-on content machines.

Omnicom wants to fuse IPG’s data and media capabilities into its own AI stack. WPP is banking on Open and WPP Media. Havas is signalling that being “deliberately different” means building a model where AI is embedded rather than bolted on. 

Taken together, these moves mark the most significant reshaping of the holding group landscape since WPP’s post-Sorrell era began. The names on your agency roster may not change overnight, but the incentives, reporting lines and product roadmaps behind them are changing fast.