Researchers uncover hidden censorship on Chinese live-streaming apps

Researchers at the University of Toronto's Citizen Lab are publishing a report today that reveals hidden keyword blacklists that are used to censor chats on three popular Chinese live streaming applications, YY, 9158, and Sina Show. Contrary to prior research and assumptions that Internet censorship in China operates under a uniform set of guidelines, the researchers found uneven implementation of censorship on the live streaming apps they studied.

Live streaming applications have gained huge popularity in China in recent years, with millions of users flocking to them to share karaoke performances, game sessions, and glimpses of their everyday lives. Popular streams attract hundreds of thousands of users who can chat with the live streamers and purchase virtual items to give them. The live streamers can in turn trade those items for cash. These platforms have given rise to a new generation of Internet celebrities who amass audiences, virtual gifts, product endorsements, and even venture capital investment from their video streams. However, the growing popularity of these apps has been met with increased pressure from the Chinese government to ensure real name registration of live streaming performers and censorship of prohibited content.

"Social media companies in China are held responsible and liable for content on their platforms, and are expected to control content, or face punishment from the government. Our research shows how this system works in practice." says Masashi Crete-Nishihata, (Research Manager, Citizen Lab).

To examine how censorship works on these applications, Citizen Lab researchers reverse engineered them—a careful process whereby the software is essentially taken apart and examined from the inside out. They found that censorship is done on the client-side, meaning all the rules to perform censorship are inside of the application running on your phone or computer. The researchers were able to collect the keyword lists used to trigger censorship of chat messages.

Jeffrey Knockel (Senior Researcher, Citizen Lab) explains: "These apps have built-in lists of blacklisted keywords. If you send any of these keywords your chat message is censored. These keyword lists give a behind the scenes look into how social media is censored in China."

The researchers tracked updates to the keyword lists over a year and found that new terms were often added in reaction to sensitive events. Overall, they found limited overlap in the blacklisted keywords used by the companies. These findings suggest that while the Chinese government may set general expectations about taboo topics, decisions on what exactly to censor are left primarily to companies themselves.

China has the most Internet users in the world and one of the strictest regimes of information control. This new report offers a nuanced and in depth view of how social media is censored in this country. "Many people believe China censors the Internet in a uniform, monolithic manner. Our research shows that the social media ecosystem in China—though definitely restricted for users—is more decentralized, variable, and slightly chaotic." says Ron Deibert, (Director of the Citizen Lab).

The researchers are releasing their report with a timeline that visualizes events censored by these applications over the past year. This report is part of the Net Alert project, an effort to make research on information controls more accessible.