The complaint was filed in U.S. District Court on Friday by Seattle Public Schools.

The social media giants are accused of making a public nuisance by marketing to children, according to the 91-page complaint.

It accuses them of escalating mental health and behavioural issues like anxiety, depression, disordered eating, and cyberbullying; making it more challenging to educate students; and pressuring schools to take actions like hiring more mental health specialists, creating lesson plans about social media’s effects, and giving teachers more training.

Tens of millions of pupils across were drawn into positive feedback loops of excessive usage and misuse of the defendants’ social media platforms, the complaint claimed. “Defendants have successfully exploited the susceptible brains of youngsters,” it stated. Worse, the defendants frequently curate and direct harmful and exploitative information towards young people.

Requests for comment from Meta, Google, Snap, and TikTok were not immediately fulfilled.

The Communications Decency Act’s Section 230 helps shield online businesses from legal responsibility for content that third parties publish on their platforms, but the lawsuit claims that this protection does not apply to the tech giants’ actions in this case.

The plaintiff claims that the defendants are responsible for their own conduct and not for what others have stated on their platforms.