Omnicom Group Inc.

What does Omnicom own?
The company owns agency networks including BBDO, DDB, TBWA, McCann, FCB, OMD, PHD, Hearts & Science, UM, Initiative, FleishmanHillard, Weber Shandwick, Ketchum, Porter Novelli, plus Acxiom, Flywheel Digital, Annalect, and Interbrand.

Is Omnicom publicly traded?
Yes. It trades on the New York Stock Exchange under ticker OMC and is an S&P 500 component.

Did Omnicom buy Interpublic?
Yes. The acquisition closed November 26, 2025. IPG shareholders received 0.344 Omnicom shares per IPG share, creating a combined company with over $25 billion in pro forma revenue.

Who founded Omnicom?
Omnicom was formed in 1986 through the merger of three agency groups: BBDO International, Doyle Dane Bernbach, and Needham Harper Worldwide.

Where is Omnicom headquartered?
The company is headquartered in New York City, New York.

Who runs Omnicom?
John Wren serves as chairman and CEO. Philippe Krakowsky and Daryl Simm serve as co-presidents and co-COOs, and Phil Angelastro is EVP and CFO.

How big is the combined Omnicom?
Post-merger the company has pro forma revenue exceeding $25 billion and more than 100,000 employees, making it the world's largest marketing and sales company.

Omnicom was created in 1986 through the so-called Big Bang merger that combined three major agency groups: BBDO International, Doyle Dane Bernbach (DDB), and Needham Harper Worldwide. The three-way combination was advertising's first giant holding company, a model built to let competing agency brands coexist under shared corporate ownership while insulating them from client conflicts.

Through the 1990s and 2000s Omnicom assembled a sprawling portfolio through acquisition: the TBWA network merged in, media units consolidated into OMD and PHD under Omnicom Media Group, and specialty businesses accumulated in public relations, CRM, branding, and healthcare. The company listed on the NYSE and grew into a Fortune 500 fixture.

The 2013 attempt to merge with Publicis in a $35 billion deal collapsed in 2014 over governance and integration disputes, leaving the industry's pecking order unchanged until technology shifted it. Omnicom spent the following decade building data capabilities, buying Acxiom's marketing solutions business in 2018 and commerce platform Flywheel in 2023, while Publicis and WPP pursued their own transformation strategies.

The December 2024 announcement that Omnicom would acquire Interpublic for approximately $13.5 billion in stock set the industry's largest-ever consolidation in motion. After a year of regulatory reviews, including European Commission and UK approvals, the deal closed November 26, 2025. IPG ceased to exist as an independent company, its agencies, McCann, FCB, IPG Mediabrands, Weber Shandwick, and others, folding into the Omnicom portfolio.

As a holding company, Omnicom's direct footprint is primarily offices and people. Its reporting covers workforce diversity, emissions from operations, and responsible marketing practices.

The more material ethical dimension is content: its agencies create and place advertising for industries including fossil fuels, alcohol, and pharmaceutical clients, drawing periodic activist pressure over the role of holding companies in contested categories.

No B Corp or equivalent certification applies at group level. The company faces the same AI-disruption scrutiny as the entire industry, with its Omni platform positioned as the response to generative AI changing creative production economics.

Client conflict management: The merger created dozens of situations where previously competing agencies for the same advertisers now share a parent, requiring conflict protocols and causing some account losses to rivals, an industry-watch item through 2026.

Integration layoffs: Post-merger restructuring eliminated thousands of positions as overlapping functions consolidated, a painful but expected cost of the combination that drew industry coverage through 2026.

Antitrust review: The deal passed EU and UK competition reviews after extended examination of its effect on media buying power, closing only after all regulatory approvals in November 2025.

Advertising industry scrutiny: The company operates under ongoing regulatory attention to data practices, media buying transparency, and the principal-based trading model that draws periodic client contract disputes across the industry.