A landmark civil trial in Los Angeles Superior Court is putting major tech companies on the stand over whether their social media platforms – especially Instagram and YouTube – were designed in ways that intentionally hook young users and harm their mental health, particularly teenagers and children.

The lawsuit centres on a woman who says she became addicted to social media at a young age and that this contributed to serious psychological issues, with lawyers arguing that features like endless scrolling and algorithm-driven recommendations were engineered to maximise engagement and profits. Meta’s CEO Mark Zuckerberg testified, denying that Instagram was deliberately addictive and defending the company’s safety measures, including its stated ban on users under 13 despite internal evidence suggesting many younger users were active.

This case is one of over 1,500 similar lawsuits nationwide and is being closely watched because if the plaintiffs succeed, it could reshape legal accountability for tech platforms and force changes in how they operate – drawing parallels to historic lawsuits that held tobacco companies responsible for addicting consumers.