Chan-jo Jun runs a law firm for IT law with 17 lawyers in Würzburg, Germany. He became known for his legal commitment against hate crime on Facebook, with which he got investigations against Mark Zuckerberg and other Facebook managers rolling and brought Facebook to court. With his team, Jun works on the use of artificial intelligence to solve legal tasks in legal departments. A particular speciality is software licensing law, especially open source software. He has been honorary judge of the Constitutional Court of Bavaria since 2022.