TikTok will appear before the US Supreme Court on Friday in a last-ditch effort to overturn a ban, in a case testing the limits of national security and free speech.
According to the BBC, the popular social media platform is challenging a law passed last year ordering the firm to be split from its Chinese owner or be blocked from the US by January 19.
The US government is arguing that without a sale, TikTok could be used by China as a tool for spying and political manipulation.
But TikTok rejects that claim, arguing it has been unfairly targeted and the measure violates the free speech of its 170 million American users.
Lower courts have sided with the government, but the case was complicated last month when President-elect Donald Trump weighed in on the dispute and asked for the enforcement of the law to be paused to grant him time to work out a deal.
Analysts have said it was not clear what the Supreme Court will decide, but that reversing the prior ruling – even with a future president’s blessing – would be unusual.