The subpoena is part of Apple’s pending legal conflict with Epic Games, in which Epic are alleging that Apple’s app store, and the mandatory 30% cut they take from everything sold there, is anti-competition. Apple want data from Valve’s Steam digital distribution platform in order to help demonstrate the size of the market available for games like Fortnite, presumably to argue that Apple have no monopoly. Specifically, Apple want information on 436 games available on the Steam store, including sales data, as a representative sample of the entire platform. In the joint discovery letter filed last week, Valve argued that the requested data was irrelevant to the case, prohibitively difficult to gather, and would require Valve to hand over information that, as a private company, they’d rather not make available. Valve made those same arguments during a virtual joint discovery hearing on Wednesday, but U.S. Magistate Judge Thomas S. Hixson sided with Apple. He did note, MacRumors report, that Apple had “salted the earth with subpoenas”, and told Valve, “don’t worry, it’s not just you.” It might seem strange that Valve, who are not a party to this lawsuit, can be compelled to hand over private information. Subpoenas are a legal tool designed to compel people or companies relevant to a case to give testimony or evidence. In this case, as the creators of the biggest major distribution platform for PC games, and as a rival to the Epic Games Store, Valve are highly relevant. Speaking personally, given the potential widespread consequences of the outcome of this case - which stretches far beyond just Fortnite or Apple - I hope that the court will have access to as much information as possible in reaching its eventual decision. The public fight between Apple and Epic began last August, when Epic added a payment method to Fortnite on iOS that bypassed Apple’s standard 30% cut of all sales on their devices. Apple immediately removed Fortnite from the app store; Epic immediately released an ironic animated short and filed suit; and the two companies have been gearing up for court and sniping at one another ever since. The case is expected to go to trial in July 2021. I’ve emailed Valve to ask for comment, and whether they intend to appeal the subpoena ruling.