Apple must face an antitrust lawsuit brought by consumers who claim the Silicon Valley tech giant has a monopoly over its app store that allows it to overcharge customers.

Monday's majority decision from the U.S. Supreme Court, written by Justice Brett Kavanaugh, said the plaintiffs are direct purchasers under the court's Illinois Brick Co. v. Illinois decision, despite claims to the contrary by Apple. Monday's majority decision upholds a ruling from the U.S. Court of Appeals for the Ninth Circuit, which had overturned a district court.

Illinois Brick held that only the first buyer from an unlawful monopoly can claim treble damages under federal antitrust laws, even if an overcharge has been passed through to indirect or subsequent buyers.