A former head of engineering at Bytedance in the United States has said the company discharged him after he voiced concern to management that it was taking user content from other platforms, mainly Instagram and Snapchat.

The dispute comes at a time when ByteDance-owned app TikTok faces growing calls for a nationwide ban from some US lawmakers regarding concerns about potential Chinese government influence over it.

Yintao “Roger” Yu said in a complaint filed on Friday in San Francisco state court that the Chinese tech company engaged in a “worldwide scheme to steal and profit from the content of others” without seeking permission.

When Yu raised these concerns to higher management, he said they dismissed them and asked him to hide the illegal program, especially from employees in the United States, as it had stricter IP laws and class actions.

He was later dismissed by ByteDance in November 2018.

Yu also said in the complaint that ByteDance created fabricated users to exaggerate its metrics and served as a useful propaganda tool for the Chinese Communist Party (CCP).

He is seeking a court order that would prohibit ByteDance from scraping content from other social media platforms. In response to the complaint, ByteDance said, “We plan to vigorously oppose what we believe are baseless claims and allegations. Yu worked for ByteDance Inc. for less than a year.”

ByteDance also responded to the scraping allegations, saying it acquired data in line with industry practice and its global policy.

In April, Montana lawmakers passed a bill to ban its short-form TikTok app from operating in the state.

In March, US lawmakers questioned TikTok’s Chief Executive Shou Zi Chew about potential Chinese influence, saying its short videos were damaging children’s mental health, reflecting bipartisan concerns about the app’s power over Americans.

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