WPP accuses Richard Foster of ‘muckraking’ in $100m lawsuit

WPP has escalated its legal battle with former Motion Content Group global chief executive Richard Foster, asking a New York court to seal parts of his amended $100 million lawsuit while launching a pointed attack on his claims.

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The holding company accused Foster of including “salacious, muckraking allegations” in the complaint. It also described the case as a “naked attempt to leverage an exorbitant payout”.

WPP moves to seal Foster claims

WPP’s application asks the Supreme Court of the State of New York to seal sections of Foster’s amended complaint that it says contain confidential client and company information.

As Campaign reported, WPP argues the filing discloses commercially sensitive material, including financial information, client details and business strategies. It also wants references to some conversations Foster had with WPP’s in-house lawyer kept from public view on attorney-client privilege grounds.

WPP said Foster “is not and never has been a whistleblower”. The company maintains his lawsuit was brought by a disgruntled former employee seeking a substantial payout.

The company has denied Foster’s underlying allegations and said it plans to file an updated motion seeking to dismiss the case.

Sony investigation enters the fight

Foster filed his amended complaint on 13 August, adding allegations about an investigation undertaken by Sony into WPP’s media buying practices.

According to Foster’s filing, the Sony investigation examined how rebates generated through client media spending were handled by GroupM, now WPP Media. The complaint alleges a Sony analysis found about $110 million was returned to clients in China during 2024, while $350 million remained in a rebate pool.

Those figures and conclusions remain allegations before the court. WPP disputes Foster’s case and argues the Sony material has little relevance to his employment claim because the investigation occurred after his departure and concerned operations in China, where he did not work.

WPP further alleged Foster included the Sony material “solely to sow discord” between the holding company and its clients.

The company has also questioned how Foster obtained the information. Its filing argues Sony had not publicly disclosed the material and points to Foster’s refusal to identify his source.

Foster to oppose sealing bid

William A. Brewer III, partner at Brewer, Attorneys & Counselors and lead counsel for Foster, said his legal team was reviewing WPP’s motion.

“Mr. Foster will oppose any attempt to seal the facts of this case from those with an interest in this matter,” Brewer said.

Foster initially sued WPP in November 2025, alleging wrongful termination and retaliation after raising concerns about the company’s treatment of media rebates. His amended complaint seeks at least $100 million in damages.

The dispute is proceeding in the Supreme Court of the State of New York, New York County.