只是看这篇，好像他也没做什么错事啊？就是请教授去中国讲学，然后给钱了。

According to the indictment:

Beginning in at least December 2013 and continuing until his arrest, Xu targeted certain companies inside and outside the United States that are recognized as leaders in the aviation field. This included GE Aviation. He identified experts who worked for these companies and recruited them to travel to China, often initially under the guise of asking them to deliver a university presentation. Xu and others paid the experts’ travel costs and provided stipends.