The U.S. Supreme Court has declined to intervene in a case involving TikTok, leaving in place a law that mandates either the sale of the app by its Chinese parent company, ByteDance, or its ban in the United States on national security grounds. This decision, effective from Sunday, marks a significant setback for the popular short-video platform, which is used by nearly half of all Americans.

In a unanimous ruling on Friday, the justices upheld the law, passed with strong bipartisan support in Congress last year and signed by President Joe Biden. The court determined that the legislation does not violate the First Amendment of the U.S. Constitution, which protects against government restrictions on free speech. This ruling affirms an earlier decision by a lower court, which had also upheld the measure following legal challenges brought by TikTok, ByteDance and several of the app's users.

“There is no doubt that, for more than 170 million Americans, TikTok offers a distinctive and expansive outlet for expression, means of engagement, and source of community. But Congress has determined that divestiture is necessary to address its well-supported national security concerns regarding TikTok’s data collection practices and relationship with a foreign adversary,” the court stated in an unsigned statement.

The court said, “We conclude that the challenged provisions do not violate petitioners’ First Amendment rights.”

The Supreme Court took swift action on the case on January 10, just nine days prior to the deadline fixed under the law. The case contested the right to free speech against national security concerns in the glimmer of the social media age. White House issued a statement which suggested that Biden would not take any action to rescue TikTok before the law's discontinuance deadline on Sunday.

Press Secretary Karin Jean-Pierre of the White House reiterated Biden's position in a statement that “TikTok should remain available to Americans, but simply under American ownership or other ownership that addresses the national security concerns identified by Congress in developing this law.”

Considering the timing, Jean-Pierre added that the steps to implement the law "will fall to the next administration."

Trump’s team has not yet issued a response to requests for comment. However, in an interview with CNN, Trump stated that the decision regarding TikTok's future would ultimately be his, though he did not specify the actions he might take.

“It ultimately goes up to me, so you’re going to see what I’m going to do,” Trump expressed. “Congress has given me the decision, so I’ll be making the decision.”

TikTok remains one of the leading social media platforms in the United States, with approximately 170 million American users, half the population, including a significant number of young people. The platform’s primary strength lies in its powerful algorithm, which curates short videos tailored to individual user preferences. Given the economic and geopolitical rivalry between China and the United States, TikTok’s Chinese ownership has been a concern for U.S. leaders for several years. This controversy played out during the final days of Biden’s presidency. Republican Donald Trump is set to take office on Monday amid heightened trade tensions between the two largest economies in the world.

In his first statement since the Supreme Court upheld the law enabling a potential TikTok ban, CEO Shou Zi Chew addressed users via a post on TikTok. He expressed gratitude to Trump, “for his commitment to work with us to find a solution that keeps TikTok available in the United States.” He added, “This is a strong stand for the First Amendment and against arbitrary censorship.”

During the case arguments, Department of Justice lawyer Elizabeth Prelogar described TikTok as a “grave threat” to U.S. national security, emphasising concerns about Chinese government control over the platform. She argued that China seeks to gather vast amounts of sensitive data on Americans and engage in covert influence operations. Prelogar stated that companies like ByteDance are compelled by the Chinese government to “secretly turn over data on social media users and carry out Chinese government directives.”

Prelogar further highlighted TikTok’s immense data set as a potential tool for harassment, recruitment, and espionage by the Chinese government, asserting that China “could weaponise TikTok at any time to harm the United States.”

The law enabling the ban was enacted in April, with the Biden administration defending it in court. TikTok, ByteDance, and several users of the app who create content challenged the measure, appealing to the Supreme Court after losing their case on December 6 at the U.S. Court of Appeals for the District of Columbia Circuit.

Trump’s opposition to the ban marks a shift from his stance during his first term when he sought to prohibit TikTok. He has since stated, “I have a warm spot in my heart for TikTok,” suggesting the platform helped him gain support among young voters in the 2024 election.

In December, Trump requested the Supreme Court to pause the law's implementation, arguing that his incoming administration should have “the opportunity to pursue a political resolution of the questions at issue in the case.” Despite Trump’s promise to “save” TikTok, many Republican allies continue to back the ban.

On Thursday, Mike Waltz, Trump’s incoming national security adviser, stated that the new administration intends to keep TikTok operational in the United States if a viable deal can be reached. Waltz explained that the administration would “put measures in place to keep TikTok from going dark,” referencing a provision in the law that allows for a 90-day extension if “significant progress” is made toward divestiture.

Senate Democratic leader Chuck Schumer also supported giving TikTok more time to secure an American buyer. He pledged to collaborate with the Trump administration “to keep TikTok alive while protecting our national security.”

TikTok CEO Shou Zi Chew is set to attend Trump’s inauguration on Monday, joining other prominent invitees.

TikTok has argued that the law jeopardises the First Amendment rights of the app, its users, and all Americans. The company claims a ban would negatively impact its users, advertisers, content creators and employees. TikTok currently employs 7,000 people in the U.S.

Unless Biden formally invokes a 90-day delay in the law’s deadline, companies providing services to TikTok or hosting the app could face legal repercussions. It remains uncertain whether TikTok’s business partners, including Google, Apple and Oracle, will continue their relationships with the platform before Trump takes office.

TikTok and ByteDance’s lawyer, Noel Francisco, told the Supreme Court that the platform is “one of America’s most popular speech platforms.” He warned that the law would force TikTok to “go dark” unless ByteDance completes a qualified divestiture.

TikTok has announced plans to shut down its U.S. operations on Sunday unless a last-minute resolution is reached. Francisco argued that the actual target of the law is speech, suggesting it stems from concerns that Americans could be “persuaded by Chinese misinformation.” However, Francisco emphasised that the First Amendment places the decision in the hands of the American people, not the government.