New court filings reveal that Sony Pictures proactively shared internal investigative findings with the defense in a high-stakes whistleblower lawsuit against WPP. The documents, submitted to the New York State Supreme Court on August 13, 2026, corroborate former GroupM executive Richard Foster’s allegations of an illicit global rebate scheme, intensifying legal pressure on the advertising giant.
The Bottom Line
- The Core Allegation: Former Motion Entertainment CEO Richard Foster alleges WPP systematically pocketed millions in client rebates through proprietary media pools.
- The Client Probe: Documents show Sony Pictures independently investigated the practices, finding that in China and other markets, $350 million was retained by WPP while $110 million was passed to clients.
- The Stakes: Foster is seeking $100 million in damages as WPP prepares a renewed motion to dismiss the amended complaint.
Unpacking the Sony Probe and the Amended Complaint
But the landscape shifted when Foster’s legal team filed an amended complaint on August 13, 2026. The new filings incorporate documents from a parallel, internal investigation conducted by Sony Pictures.
Out of funds connected to the regional activity, approximately $110 million reached clients, whereas $350 million was allegedly wrongfully kept by WPP.
The Sony investigation dovetailed with scrutiny from Chinese authorities, which initiated a probe into GroupM China employees in 2023. That inquiry resulted in severe legal consequences last month. Di Fei, the former chief investment officer at WPP Media’s China operations, received a life sentence following a bribery and kickback conviction. Several other employees also received prison terms, though Fei is currently appealing the verdict. WPP has maintained throughout the process that the corporate entity was not a target of the investigation and cooperated fully.
Inside the Proprietary Media Mechanism
The mechanics of the alleged rebate scheme relied heavily on obfuscation. Sony’s findings point to Proprietary Media—often referred to as PM or Programmatic—as the core distribution channel for hidden margins.
The amended complaint outlines how the mechanism functioned in practice:
According to Sony representatives, Proprietary Media (designated as “PM/Programmatic”) serves as a primary vehicle for distributing Rebates, where the alleged ‘discount’ provided by WPP to Clients on Inventory is altered: WPP covers only a part of the actual acquisition expense for the Inventory, uses money drawn from the Rebate pool to cover the remaining balance, and retains the resulting margin as nearly pure profit that remains protected from audits.
Foster’s filing asserts that this framework was deployed globally to artificially inflate earnings at WPP. To support these claims, Sony presented contractual language, transaction-level financial reporting, internal emails regarding rebate amounts, and documentation of WPP tracking systems.
When confronted with evidence that 80% media discounts were funded through unpublished rebate pools, WPP representatives reportedly offered no counter-explanation, stating they did not want to “know the answer,” according to the complaint.
Executive Awareness and Market Valuation Pressures
The legal jeopardy for WPP extends to top-tier management conversations. The court documents allege that internal executives acknowledged the structural fragility of these rebate practices. Nicola McCormick, general counsel at WPP and formerly general counsel at GroupM, allegedly characterized the risk posed by GroupM Trading’s rebate policies as “existential” when questioned directly by Foster.
| Metric / Data Point | Value / Detail |
|---|---|
| Target of Lawsuit | WPP |
| Plaintiff Seeking | $100 million in damages |
| Sony Probe Findings (China) | $350M retained by WPP vs. $110M passed to clients |
| Initial Complaint Filing Date | October 2025 |
| Amended Complaint Filing Date | August 13, 2026 |
As markets await the upcoming hearing on WPP’s motion to dismiss, the company continues to push back against the litigation. A WPP spokesperson issued a formal statement regarding the latest legal maneuver: “This amended complaint, filed just prior to the hearing, is an attempt to avoid its dismissal. Both complaints are baseless and without merit, and WPP will be re-filing an updated motion to dismiss. We have confidence that this matter will be resolved through due legal process.”
Disclaimer: The information provided in this article is for educational and informational purposes only and does not constitute financial advice.
