S4 Capital's Martin Sorrell predicts holding companies will break up

On yet another Advertising Week New York panel S4 Capital Executive Chairman Martin Sorrell graced with his presence, the former longtime CEO and founder of WPP said he predicts the holding companies will eventually be “broken up” and consolidated.Sorrell was joined on stage Wednesday by S4 Capital’s MediaMonks Founder and Chief Operating Officer Wesley ter Haar and MightyHive President of the Americas Emily Del Greco. “The proof of that is IPG, which appears to