By Li Yuan

New York Times News Service

Li Chengzhi had a lot to learn when he first got a job as a professional censor.

Like many young people in China, the 24-year-old recent college graduate knew little about the 1989 Tiananmen Square crackdown. He had never heard of China’s most famous dissident, Liu Xiaobo, the Nobel Peace Prize laureate who died in custody two years ago.

Now, after training, he knows what to look for — and what to block. He spends his hours scanning online content on behalf of Chinese media companies looking for anything that will provoke the government’s wrath. He knows how to spot code words that obliquely refer to Chinese leaders and scandals, or the memes that touch on subjects the Chinese government doesn’t want people to read about.

Li, who still has traces of youthful acne on his face, takes his job seriously. “It helps cleanse the online environment,” he said.

For Chinese companies, staying on the safe side of government censors is a matter of life and death. Adding to the burden, authorities demand that companies censor themselves, spurring them to hire thousands of people to police content.

That in turn has created a growing and lucrative new industry: censorship factories.

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. In the heart of a high-tech industrial area, the space is bright and new enough that it resembles the offices of well-funded startups in tech centers like Beijing and Shenzhen. It recently moved to the space because customers complained that its previous office was too cramped to allow employees to do their best work.

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

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. More content is considered sensitive. Punishments are getting more severe.

Once circumspect about its controls, China now preaches a vision of a government-supervised internet that has surprising resonance in other countries. Even traditional bastions of free expression like Western Europe and the United States are considering their own digital limits. Platforms like Facebook and YouTube have said that they would hire thousands more people to better keep a handle on their content.

Workers like Li show the extremes of that approach — one that controls what more than 800 million internet users in China see every day.

Beyondsoft employs over 4,000 workers like Li at its content reviewing factories. That is up from about 200 in 2016. They review and censor content day and night.

Beyondsoft has a team of 160 people working four shifts a day to review potentially politically sensitive content on a news aggregating app.

For the same app, Beyondsoft has another team reviewing potentially vulgar or profane content. Like the rest of the world, China’s internet is rife with pornography and other material that many users might find offensive.

New hires start with weeklong “theory” training, during which senior employees teach them the sensitive information they didn’t know before.

“My office is next to the big training room,” Yang said. “I often hear the surprised sounds of ‘Ah, ah, ah.’”

“They didn’t know things like June 4,” he added, referring to the 1989 Tiananmen Square crackdown. “They really didn’t know.”

Beyondsoft has developed an extensive database based on such information that Yang calls one of its “core competencies.” It also uses anti-censorship software to regularly visit what it calls anti-revolutionary websites that are blocked by the Chinese government. It then updates the database.

New employees study the database much like preparing for college entrance exams. After two weeks, they have to pass a test.

The screen saver on each computer is the same: photos and names of current and past members of the Politburo Standing Committee, the Communist Party’s top leadership. Workers must memorize those faces: Only government-owned websites and specially approved political blogs — a group on what’s called a white list — are allowed to post photos of top leaders. Workers are briefed at the beginning of their shift on the newest censoring instructions sent by clients, which the clients themselves receive from government censors. Workers then must answer about 10 questions designed to test their memory. The results of the exam affect the workers’ pay.

Take, for example, a Hong Kong news site’s 2017 commentary that compared the six Chinese leaders since Mao Zedong to emperors during the Han dynasty. Some Chinese users started using the emperors’ names when referring to the leaders. Beyondsoft’s workers have to know which emperor’s name is associated with which leader. References to George Orwell’s novel “1984” are forbidden

Beyondsoft’s software trawls through webpages and marks potentially offensive words in different colors. If a page is full of color-coded words, it usually requires a closer look, according to the executives. If there are only one or two, it’s pretty safe to let it pass.

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. Politically sensitive words make up one-third of the total, followed by words related to pornography, prostitution, gambling and knives.

Workers like Li make $350 to $500 a month, about average pay in Chengdu. Each worker is expected to review 1,000 to 2,000 articles during a shift. Articles uploaded to the news app must be approved or rejected within an hour. They don’t work much overtime because longer hours could hurt accuracy, said Yang, the executive.

When asked whether he had shared with family and friends what he learned at work, such as the Tiananmen crackdown, Li vehemently said no.

“This information is not for people outside to know,” he said. “Once many people know about it, it could generate rumors.”

The crackdown was history. It wasn’t a rumor. How would he reconcile that?

“For certain things,” he said, “one just has to obey the rules.”