The ban takes effect one day before Donald Trump’s inauguration. Trump had pledged in his campaign to “save TikTok” — putting the president-elect in a position of possibly defending a law he opposed, or finding a way to defang it. Trump’s transition team did not immediately respond to questions about his plans.

TikTok indicated it will appeal the decision to the Supreme Court — which could drag out the high-profile fight that marks a historic strike at tech’s ties to China and could have far reaching implications for digital free speech.

“The Supreme Court has an established historical record of protecting Americans’ right to free speech, and we expect they will do just that on this important constitutional issue,” said TikTok spokesperson Michael Hughes. “The TikTok ban, unless stopped, will silence the voices of over 170 million Americans here in the US and around the world on January 19th, 2025.”

The 92-page ruling lands more than seven months after TikTok, ByteDance and other groups sued to block the law in May, arguing that it suppresses speech by banning a platform used by more than half the U.S. population.

In its ruling, the court sided with lawmakers and the Justice Department that had said TikTok was a national security threat. In particular, lawmakers had warned that Chinese authorities could force ByteDance to hand over Americans’ data or manipulate its algorithm to promote Beijing’s interests.

“The First Amendment exists to protect free speech in the United States. Here the Government acted solely to protect that freedom from a foreign adversary nation and to limit that adversary’s ability to gather data on people in the United States,” Ginsburg wrote Friday. Neomi Rao, who was appointed by Trump, concurred, as did Obama appointee Sri Srinivasan, though he said he reached his conclusion via “an alternative path.”

The politics of a rescue

While TikTok pursues its appeal, a greater factor in the app’s survival may be maneuvers in Washington.

Legal observers say Trump could try several avenues to make good on his campaign promise and block the law’s intent. He can pressure Congress to repeal the law, order his Justice Department not to enforce it, or get around its language by declaring that TikTok already meets the law’s requirements without any actual changes.

Some Republican hawks who supported the bill said they did not anticipate Trump intervening to block its effects.

“I don’t think it probably is possible,” Sen. Josh Hawley (R-Mo.) told reporters on Thursday. “The only other alternative if no sale comes together, then the law requires it to be banned. I mean, you could change the law.” Sen. Rick Scott (R-Fla.) echoed that stance, telling POLITICO that he believes Trump will “enforce the laws of this country” and adding “if you don’t like them, you go to the legislature and you get them changed.” House China Chair John Moolenaar (R-Mich.) too has said he doesn’t expect Trump to rescue TikTok from the law’s requirements.

Other influential China hawks like Sen. Marco Rubio (R-Fla.) and Rep. Jim Jordan (R-Ohio), have signaled they’d defer to Trump, despite voting for the law. Trump tried unsuccessfully to ban the app in 2020 before flip-flopping years later.

Trump did not post to his Truth Social platform about the case after the court issued its ruling on Friday, though he boasted about his own TikTok account’s strong performance a day prior. His transition team has said Trump “will deliver” on “the promises he made on the campaign trail,” without addressing the TikTok law directly.

Trump’s former aide John McEntee, who has more than 3 million TikTok followers, stressed the importance for TikTok to prevail as a “truly free and open platform” and urged Trump to act in a statement Friday. “The incoming administration has shown it wants to take a different course and I look forward to seeing them to do that quickly,” he said.

The American Civil Liberties Union blasted the decision Friday, saying the ruling set a “flawed and dangerous precedent, one that gives the government far too much power to silence Americans’ speech online.”

What’s next

The law gives TikTok until Jan. 19 to find a new owner or face a ban, with a possible 90-day extension. On Friday billionaire Frank McCourt said a group of investors he assembled is “prepared to move forward with our bid for TikTok,” although the video-sharing company has argued in previous legal filings that divestiture is simply “not possible technologically, commercially, or legally.”

Besides McCourt, other prospective buyers include Trump’s former Treasury Secretary Steven Mnuchin and reportedly Bobby Kotick, the former CEO of video game company Activision Blizzard.

TikTok will not immediately vanish if it’s banned. The law is enforced against app stores, which would need to stop hosting the platform to avoid billion-dollar fines. That would prevent new downloads and doom the app to a slow death in the U.S.

Any attempts by Trump to work around Congress to save TikTok would still leave companies like Google and Apple on the hook, according to former DOJ official Alan Rozenshtein, who spoke to POLITICO in November before the ruling.

“They’re the ones that are going to be punished under this law if they provide services to TikTok,” said Rozenshtein, who now teaches at the University of Minnesota Law School. “If you’re the general counsel of Apple, you’re still nervous.”

If the Supreme Court agrees to hear the case, as legal watchers expect, it can choose to grant a stay, effectively pausing any ban.