A former WPP exec is suing the ad agency giant, claiming he was fired after flagging an alleged kickback operation
1. Former WPP exec alleges wrongful termination over kickback concerns. 2. WPP could face significant legal and financial ramifications from the lawsuit. 3. Concerns about undisclosed rebates echo past industry scandals. 4. Foster estimates GroupM improperly retained $1.5-$2 billion from rebates. 5. WPP's share price has halved amid competitive losses and declining revenues.