TikTok, the popular short video-sharing app owned by ByteDance, denies being influenced by Beijing to censor content posted by its users, as US Senator Marco Rubio called on Washington to investigate its operations over national security concerns.

Rubio, the Republican lawmaker from Florida, requested the US Treasury Department in a letter on Wednesday to investigate ByteDance’s 2017 acquisition of social media start-up Musical.ly, whose operations in Shanghai and San Monica, California, were later merged with TikTok in 2018.

“These Chinese-owned apps are increasingly being used to censor content and silence open discussion on topics deemed sensitive by the Chinese Government and Communist Party,” Rubio wrote in the letter. Treasury Secretary Steven Mnuchin chairs the Committee on Foreign Investment in the United States (CFIUS), an inter-agency panel that reviews the national security implications of foreign mergers, acquisitions and takeovers of any US business.

US Senator Marco Rubio, a Republican lawmaker from Florida, accuses ByteDance-owned TikTok of censoring user content on behalf of the Chinese government. (Picture: EPA-EFE)

TikTok, which has a version for mainland China called Douyin, said it adheres to US laws, and that all its US data are stored in the country. “Our content and moderation policies are led by our US-based team and are not influenced by any foreign government,” a TikTok spokeswoman said on Thursday. “The Chinese government does not request that TikTok censor content, and would not have jurisdiction regardless, as TikTok does not operate there.”

The spokeswoman added that TikTok also consults “with a number of third-party advisers, and [is] looking into the formation of a committee of leading industry organisations and experts to help us further refine and regularly assess our policies and implementation, and increase transparency.”

The US lawmaker’s call for a CFIUS investigation makes Beijing-based ByteDance the latest Chinese technology company to find itself in Washington’s crosshairs, as the world’s two-largest economies pursue talks this week to end their trade war.

On Monday, the US Commerce Department added 28 Chinese public security bureaus and companies on a trade blacklist over Beijing’s treatment of Uygur Muslims and other predominantly Muslim ethnic minorities.

The companies added to the so-called Entity List include facial recognition start-ups Megvii and Yitu Technology, video surveillance specialists Hangzhou Hikvision Digital Technology and Dahua Technology, artificial intelligence champions SenseTime Group and iFlyTek, as well as Xiamen Meiya Pico Information and Yixin Science and Technology Co.

TikTok was said to be instructing its moderators to censor videos that mention politically sensitive topics, including “Tiananmen Square” or the banned religious group “Falun Gong,” according to a report by The Guardian in September, citing leaked documents detailing the site’s moderation guidelines.

TikTok, which is marketed as Douyin in mainland China, has been embroiled in regulatory issues in different overseas markets amid the video-sharing app’s steady international expansion. (Picture: Simon Song/SCMP)

ByteDance has said the version which that report referred to was already retired in May, and that the current guidelines do not reference specific countries or issues.

A search conducted by the Post on the terms “Tiananmen” and “Falun Gong” on TikTok turned up a number of videos or accounts relevant to those subjects.

To be sure, Beijing-based ByteDance – a seven-year-old start-up that was reportedly valued at US$78 billion last year – has been embroiled in regulatory issues in different overseas markets amid TikTok’s steady expansion. TikTok, which allows users to watch as well as create short videos with music, stickers and animation as special effects, has become one of the most heavily downloaded apps worldwide since it was launched in 2016.

ByteDance merged teen karaoke app Musical.ly with TikTok to create one global app under one brand, in a push to become the world’s go-to destination for short-form video content and creation. The company said in June that its apps, including Chinese news aggregator Jinri Toutiao, recorded 1 billion monthly active users globally as of January this year.

TikTok’s rapid international growth, however, has been marred by problems with regulators in Indonesia, the US and India. In February, ByteDance agreed to pay a US$5.7 million fine to the US Federal Trade Commission over TikTok’s illegal collection of personal information from children. The commission said TikTok failed to obtain parental consent from users under the age of 13 based on the country’s Children’s Online Privacy Protection Act.

Despite that regulatory setback in the US, TikTok was the third most downloaded app in the country last month, behind Instagram and YouTube, according to data from app analytics firm Sensor Tower. It also ranked TikTok again as the world’s most downloaded app from a publisher based in China, with more than 156 million new installations in the second quarter.