TikTok is still fighting to remain operational in the United States, but a new lawsuit could complicate things even further for the company. A former ByteDance executive has alleged TikTok’s owner used bots and stolen content to inflate the app’s engagement.

The lawsuit, filed by former head of engineering Yintao Yu and reported by The New York Times, claims that ByteDance wrongly fired Yu after he pushed back on company practices like stealing other apps’ material. It also claims that ByteDance acted as a “useful propaganda tool for the Chinese Communist Party,” and that China-based employees could access US users’ data.

As The New York Times points out, Yu’s allegations “describe how ByteDance operated five years ago” and come after “several years of mediation.” Still, the claims are still likely to fuel even more scrutiny for TikTok, which is facing the prospect of a nationwide ban in the United States. Lawmakers and other officials have claimed that TikTok is a national security threat and that the app can’t be trusted to protect the data of US users.

Yu’s allegations could intensify those concerns. The lawsuit details “a special unit of Chinese Communist Party members” at ByteDance offices in Beijing who “guided how the company advanced core Communist values.” He also alleges that ByteDance employees manipulated Douyin, the Chinese version of TikTok, to suppress content about protests in Hong Kong and “elevate content that expressed hatred for Japan.”

Some of Yu’s claims also relate directly to TikTok. Notably, he claims that ByteDance engineers stole popular content from apps like Instagram and Snapchat and put the videos onto TikTok. He also alleges that the company used bot accounts to juice the app’s engagement metrics when it was just starting out and trying to gain a foothold in the US. (Yu left the company in November 2018, shortly after ByteDance rebranded Musical.ly as TikTok.)

A spokesperson for ByteDance told Engadget: “We plan to vigorously oppose what we believe are baseless claims and allegations in this complaint. Mr. Yu worked for ByteDance Inc. for less than a year and his employment ended in July 2018. During his brief time at the company, he worked on an app called Flipagram, which was discontinued years ago for business reasons.” On the allegation of scraping, they also said: “ByteDance is committed to respecting the intellectual property of other companies, and we acquire data in accordance with industry practices and our global policy.” 

TikTok has repeatedly tried to downplay its ties to ByteDance and China, including in CEO Shou Zi Chew’s congressional testimony in March. The company has also dedicated more than a billion dollars into Project Texas, which aims to wall off TikTok’s US user data from the rest of ByteDance in an effort to allay the concerns of US regulators.

Update 05/12/23: Added a statement from ByteDance.