Apple took a trip to the Supreme Court and left with a loss.
A district court decision had said that the iPhone users did not have standing to bring their antitrust claim because the developers - not Apple - are the ones selling the apps.
The Supreme Court is allowing consumers to pursue an antitrust lawsuit that claims Apple has unfairly monopolized the market for the sale of iPhone apps.
Apple´s online marketplace is the sole avenue for apps for its iPhone and other mobile devices, and the company has paid out more than $100 billion to developers since launching the store a decade ago.
If a court rules that the App Store is an unfair use of monopoly power, Apple could stand to pay out hundreds of millions of dollars to consumers.
The Supreme Court's majority opinion was written by Justice Brett Kavanaugh - a conservative Trump appointee - joined by the court's four liberal-leaning judges, Justices Ruth Bader Ginsburg, Stephen Breyer, Sonia Sotomayor and Elia Kagan.More news: NBA Youngboy's GF Reportedly Shot Outside Trump Hotel in Miami
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The court has not declared Apple monopolists yet, but this ruling does allow the case to proceed. Four iPhone owners sued the company in a case titled Apple v. Pepper, which alleges that Apple has illegally monopolized the app aftermarket for iPhones as the company's App Store charges a 30 percent commission to developers that wish to publish iPhone apps.
Tom's Hardware has reached out to Apple for comment, but did not receive an immediate response. Apple said the consumers were indirect purchasers, at best, because any overcharge would be passed on to them by developers.
"Apple's theory would provide a roadmap for monopolistic retailers to structure transactions with manufacturers or suppliers so as to evade antitrust claims by consumers and thereby thwart effective antitrust enforcement", Kavanaugh wrote.
They claim that this puts Apple in breach of anti-trust laws.
As of this writing, Apple's stock is down 4.9% percent on the news.