Enlarge / Andrew J. Pincus, attorney for TikTok and ByteDance, leaves the E. Barrett Prettyman US Court House with members of his legal team as the US Court of Appeals hears oral arguments in the case TikTok Inc. v. Merrick Garland on September 16 in Washington, DC. (credit: Kevin Dietsch / Staff | Getty Images News)

The fight to keep TikTok operating unchanged in the US reached an appeals court Monday, where TikTok and US-based creators teamed up to defend one of the world's most popular apps from a potential US ban.

TikTok lawyer Andrew Pincus kicked things off by warning a three-judge panel that a law targeting foreign adversaries that requires TikTok to divest from its allegedly China-controlled owner, ByteDance, is "unprecedented" and could have "staggering" effects on "the speech of 170 million Americans."

Pincus argued that the US government was "for the first time in history" attempting to ban speech by a specific US speaker—namely, TikTok US, the US-based entity that allegedly curates the content that Americans see on the app.