France, March 26 -- The verdict hands plaintiffs in more than a thousand similar pending cases significant leverage -- and signals to the broader tech industry that juries are prepared to hold social media companies accountable for the mental health toll of their design choices.

The jury answered yes to all seven questions on verdict forms for both companies, finding that Meta and YouTube were negligent in the design and operation of their platforms and that their negligence was a substantial factor in causing harm to the plaintiff.

Jurors also found that both companies knew or should have known their services posed a danger to minors, that they failed to adequately warn users of that danger, and that a reasonable platform operator woul...