App developer ByteDance, headquartered in Beijing, was suspected of running a subsidiary in contravention of a law that restricts a variety of Chinese firms, including social media companies, from operating offices in Taiwan, the Mainland Affairs Council, which is responsible for China policy, said on Sunday.

The identical apps, which share an interface but not content, cater to respective Chinese-language and international markets. In Taiwan, home to an estimated 5 million of TikTok’s over 1 billion-strong global user base, the app lags behind Meta-owned Facebook and Instagram.

Authorities launched a probe into TikTok’s local commercial interests on December 9, the MAC’s statement said. Also on Sunday, the Liberty Times newspaper reported a suspected ByteDance office, registered in 2018, was recruiting Taiwanese social media influencers to help boost their influence abroad.

In a statement to the local and foreign press, the streaming app denied operating any legal entities in Taiwan.

Taiwan has long been wary of allowing Chinese companies to establish a foothold in the island nation. Flouting the enterprise law carries a three-year prison term for business owners as well as a fine of 15 million New Taiwan dollars (about $488,000).

China was using TikTok and other platforms “to carry out cognitive operations and infiltration other countries,” the MAC said. “There is a high risk the Chinese government is collecting users’ personal data.”

TikTok, which has been put under microscopic examination in the United States, denies user data is accessible from China.

Taiwan’s digital ministry, formally constituted this past August by President Tsai Ing-wen, lists TikTok among “products that endanger national information security,” blacklisting them from government devices like smartphones, tablets and computers.

Wellington Koo, Tsai’s national security adviser, said last week in a judiciary committee in the island’s legislature that the civil service had been banned from using Chinese electronic devices in December 2020. The restriction was extended to cover their use in government buildings this year.

Taipei was widely reported to be considering a private-sector ban on TikTok and other Chinese social media apps this month, following a similar move by India in 2020.

Koo repeated popular assessments of TikTok as posing concerns related to personal data and cybersecurity but said a private sector ban would be “a big deal.”

At a separate committee hearing earlier the same week, Li Meng-yen, the general secretary of the Executive Yuan, which comprises Taiwan’s cabinet, said a civilian ban on TikTok would have implications for freedom of speech, which “the government is obligated to protect.”

After a number of U.S. states moved to ban TikTok from public devices, the Senate voted on December 14 to restrict the app at the federal level. The bill would require similar backing in the House before being considered by President Joe Biden.

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