Who are the big 5 advertising agencies?
The "Big 5" advertising agency holding companies — the parent groups behind hundreds of individual agencies — are WPP (which owns Ogilvy, VMLY&R, GroupM), Omnicom (BBDO, TBWA, DDB), Publicis Groupe (Publicis Worldwide, Saatchi & Saatchi, Leo Burnett), Interpublic (McCann, MullenLowe, R/GA), and Dentsu. Together they represent the majority of global agency spending. Independent agencies fill a distinct market segment focused on flexibility and specialization.
Why this matters
This question shows up regularly in Google's People Also Ask for the "marketing agency" query, which is a signal that buyers in this space are asking it constantly during their research phase. The answer above is written from The Wall's editorial position — we index 2,286 verified US growth-services vendors across 10 pillars and see how these questions map to actual buying decisions.
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