Sony Probe Allegations Put WPP’s Media Rebate Practices Under Scrutiny

A new filing in a lawsuit from former GroupM executive Richard Foster alleges Sony investigated WPP and concluded the company improperly withheld rebates from clients. The filing says Sony presented findings to WPP in 2025 and described the alleged conduct as a “global crime scheme” across several markets, including China. Business Insider reports the case centers on whether WPP put its own interests ahead of clients by using parts of advertising budgets to maximize profits without client consent.

The lawsuit alleges WPP’s media investment arm, GroupM, negotiated rebate deals with media owners by leveraging clients’ combined ad spending. It says WPP used “intermediary brokers” to hold some rebates rather than disperse them to clients, then used rebate funds to subsidize ad inventory and keep the margin as profit. A purported Sony slide cited in the lawsuit claims about $110 million was passed back to clients in China in 2024, while $350 million remained in a rebate pool “for later utilization” by WPP.

WPP declined to comment on the alleged Sony review and said Foster’s amended complaint was an attempt to avoid dismissal ahead of a court hearing. The company said both complaints are “baseless and without merit” and that it would re-file an updated motion to dismiss. Sony said it does not comment on pending litigation, and the suit remains ongoing.

Media rebates are not inherently illegal, but the article notes they can raise transparency and accounting issues if not properly disclosed. The broader industry debate includes “principal media,” where agencies buy media at a discount, resell it to clients, and make a margin. Supporters argue the model can be cost-effective, while critics say it may create conflicts of interest if agencies steer marketers toward inventory the agency has already bought.