The US Supreme Court ruled against TikTok on Friday in its challenge to a federal law that would have required the popular short-video app to be sold by its Chinese parent company ByteDance or banned in the United States on January 19. The justices ruled that the law, passed by an overwhelming bipartisan majority in Congress last year and signed by Democratic President Joe Biden, did not violate the US Constitution’s First Amendment protection against government abridgement of free speech. The justices overturned a lower court’s decision that upheld the measure after it was challenged by TikTok, ByteDance and some of the app’s users. The Supreme Court acted speedily in the case, having held arguments on January 10, just nine days before the deadline set under the law. The case pitted free speech rights against national security concerns in the age of social media. TikTok is one of the most prominent social media platforms in the United States, used by about 270 million Americans – roughly half the country’s population, including many young people. TikTok’s powerful algorithm, its main asset, feeds individual users short videos tailored to their liking.