Valve Corporation, the owner of the Steam digital gaming storefront, faces a massive collective legal claim of approximately $900 million in the United Kingdom following a greenlight ruling by the Competition Appeal Tribunal. The lawsuit alleges that Steam abused its dominant market position by enforcing unfair platform parity clauses that prevent developers from offering lower prices on rival stores, imposing mandatory in-game add-on purchase restrictions, and charging excessive 30% commission fees that ultimately drive up prices for British consumers.