A federal appeals court in the United States has allowed more than 3,000 lawsuits to proceed against major social media companies — including Meta, Alphabet's Google, ByteDance's TikTok and Snap's Snapchat — over allegations that they deliberately designed their platforms to be addictive to children and teenagers. The San Francisco-based 9th US Circuit Court of Appeals rejected the companies' attempts to halt the litigation before trial, ruling that their appeals had been filed prematurely.

At the heart of the legal dispute was Section 230 of the Communications Decency Act of 1996, a landmark law that generally shields online platforms from liability over content posted by their users. The companies argued that this protection also covered claims that they failed to warn the public about the addictive nature of their products. The court disagreed, drawing a clear distinction: Section 230 provides a defence against liability, not immunity from being sued in the first place — making the appeal premature. The panel also denied Meta's separate request to delay a trial, brought by 29 state attorneys general, that was due to begin this week. Prosecutors in that case allege Meta illegally collected children's data, engineered its platforms to keep young users hooked, and misled the public about safety risks.

The cases, centralised before US District Judge Yvonne Gonzalez Rogers in Oakland, California, have been filed by a broad coalition of plaintiffs — states, municipalities, school districts and individual families. They allege that the companies knowingly built addictive products that have contributed to surging rates of depression, anxiety, body-image disorders and a broader mental health crisis among young people. The lawsuits seek damages, penalties and restitution. The litigation has already produced significant early verdicts: a Los Angeles jury in March found Meta and Google negligent and awarded $6 million to a young woman who says she became addicted to Instagram and YouTube as a child. Separately, a New Mexico court ordered Meta to pay $375 million after a jury found it had misled consumers, with a judge later adding a $567 million penalty for creating a public nuisance. Both companies have denied wrongdoing and said they intend to appeal.

The ruling arrives amid growing international pressure on social media platforms over harm to minors. Australia has enacted a world-first ban on social media for children under 16, with non-compliant companies facing penalties of up to AU$49.5 million. France plans to bar under-15s from social media and restrict mobile phones in high schools. Britain has also signalled similar legislation. Monday's decision means further trials — including one brought by school districts scheduled for February — are now cleared to move forward, and attorneys representing plaintiffs said it would force a public reckoning over what companies knew about their products' effects on children and when they knew it.