https://www.straitstimes.com/asia/east-asia/censoring-chinas-internet-for-stability-and-profit

China has built the world's most extensive and sophisticated online censorship system. It grew even stronger under President Xi Jinping, who wants the Internet to play a greater role in strengthening the Communist Party's hold on society.

Li works for Beyondsoft, a Beijing-based tech services company that, among other businesses, takes on the censorship burden for other companies. He works in its office in the city of Chengdu.

"Missing one beat could cause a serious political mistake," said Yang Xiao, head of Beyondsoft's Internet service business, including content reviewing. Beyondsoft has declined to disclose which Chinese media or online companies it works for, citing confidentiality.

Many online media companies have their own internal content review teams, sometimes numbering in the thousands. They are exploring ways to get artificial intelligence to do the work.

The head of the AI lab at a major online media company, who asked for anonymity because the subject is sensitive, said the company had 120 machine learning models.

According to Beyondsoft's website, its content monitoring service, called Rainbow Shield, has compiled over 100,000 basic sensitive words and over 3 million derivative words.