China's top internet watchdog said on Friday that tech giants such as Tencent and Alibaba have submitted details of algorithms used in some of their products.

The Cyberspace Administration of China (CAC) issued a list of 30 algorithms used in some of the country's most popular applications, such as Alibaba's Taobao, Tencent's WeChat, and ByteDance's Douyin, along with brief explanations of their use.

For instance, Taobao claims that its algorithm is used to recommend users with goods they may be interested in based on their searches, footprints, etc. By identifying user preferences through clicks and comments, ByteDance's algorithm is able to recommend content to Douyin users. Douyin is the TikTok's sister app in China.

The tech companies' submissions come in response to a push by authorities to increase oversight of tech firms' algorithms. Provisions on the Administration of Algorithm Recommendation for Internet Information Services, formulated CAC, came into effect on March 1, requiring companies to be open, transparent, and impartial when using algorithms.

Under the regulation, companies need to disclose algorithm-related information so that regulators can evaluate and record them. Simultaneously, a system for classification and hierarchical management of algorithm recommendation service providers was established.

In April this year, CAC launched a special campaign to rectify "algorithm abuse", focusing on reviewing social network platforms and urging them to use algorithms to spread positive news and information, and severely crack down on negative illegal information. The campaign will run until the end of 2022.

The list is the first since China passed new rules for algorithm recommendation services and launched a filing system requiring firms and companies to disclose they used in their apps.

Other companies on the list included Chinese online search giant Baidu, short video platform Kuaishou, microblogging site Sina's Weibo, and food delivery app Meituan.

Cover image by Markus Spiske on Unsplash