The court is hearing oral arguments on TikTok’s bid to block a law that would lead to its ban in the U.S. starting Jan. 19 if it isn’t sold by its Chinese owner.

The Supreme Court signaled in oral arguments Friday that it may uphold the federal ban on TikTok, potentially leaving it up to President-elect Donald Trump to try and keep the app legal once he takes office — but the president-elect has limited options if the law is upheld, and any attempts to stop it could be challenged in court.

Congress labeled the app’s Chinese ownership a national security risk and passed a law that would ban the social media platform unless it was sold. TikTok and creators say that violates their free speech rights.