TikTok has worked to separate its operations from Chinese owner ByteDance, particularly as foreign governments have scrutinized or punished the video app over fears that Beijing could hijack it for its own purposes. TikTok is incorporated in California; its CEO sits in Singapore; its chief information security officer is based in the U.S.; and the company says data on its hundreds of millions of users are stored on servers outside China.

But TikTok’s ties to China remain deep: There are more algorithm engineers in China working on TikTok’s video recommendation engine than in any other international offices, according to people with knowledge of the matter. ByteDance also has China-based product managers, monetization experts and data analysts who all work on TikTok, and ByteDance’s Beijing office recently sought to hire a senior engineer to analyze TikTok’s user data.