The case is very old, so it is worth explaining again: in 2011, a press conference accused Apple of operate an illegal monopoly by not allowing users of iPhones and iPads to download applications from sources other than App Store, reducing consumer choice.
In 2013, a US District Court judge decided to dismiss the case due to errors related to the complaint itself; subsequently, in 2017, the U.S. Court of Appeals ruled that the case could indeed continue with its charges. As a result, this ensured a review of the US Supreme Court, which will now assess the Court of Appeal's decision to reinstate the case.
It is worth mentioning that the US Department of Justice filed a amicus brief in support of Apple, requesting the Supreme Court to reverse the decision. Since the beginning of the imbroglio, Apple has argued that it does not set prices for paid applications and that charging a 30% commission on the distribution of paid applications and internal purchases is something that does not violate American antitrust laws.
For now, Ma remains to hope that the Supreme Court will agree that the case should be dismissed; so far no date has been released for the audience, so we'll see what happens.