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.

He bought his first home by devising a formula to identify Beijing’s best community. And he became China’s richest person after creating TikTok, the massively popular app built around an algorithm that predicts the videos people would enjoy based on their previous activity.