WPP’s GroupM spends $76 billion a year on media. Ginny Marvin on August 28, 2015 Martin Sorrell. Image copyright by World Economic Forum/Photo by Michael Wuertenberg The world’s largest ad agency holding company, WPP, spends $76 billion annually on advertising through its buying and planning arm, GroupM. On Thursday, GroupM announced an advertising deal with BuzzFeed. The companies … Continue reading Here’s Where The World’s Largest Media Buyer Spends Its Money →