The Interpublic Group of Companies, Inc. was an American advertising company based in New York City. It consisted of the five major networks FCB, IPG Mediabrands, McCann Worldgroup, MullenLowe Group and Marketing Specialists, as well as several independent specialty agencies in the areas of public relations, sports marketing, talent representation and healthcare. Prior to the Omnicom acquisition, it was one of the "Big Four" agency companies, alongside WPP, Publicis, and Omnicom. The company was acquired by Omnicom in 2025, and its operations were later folded into Omnicom following the acquisition. Wikipedia