Zuckerberg Testifies in Landmark Youth Social Media Trial

On February 18, 2026, Mark Zuckerberg testified in Los Angeles Superior Court, where jurors are weighing a lawsuit that claims Instagram and YouTube were designed to addict children and worsen mental health. The plaintiff, a 20-year-old known as KGM in court filings, has said she began using YouTube at age six and Instagram around age nine.

Throughout the trial, attorneys have shown internal company messages and research documents that discuss engagement goals, while plaintiffs’ lawyers argue that features like infinite scroll, autoplay, likes and beauty filters were engineered to keep young people on the platforms. Defenders for Meta and Google have said the companies were responding to user demand, that many children lie about their ages, and that social media often served as a refuge for a young person in difficulty.

Zuckerberg was questioned by Mark Lanier and pressed about whether Meta once set goals tied to time spent on its apps; he said the company has changed its approach and that it now focuses on building valuable experiences rather than maximising time. He said: "I think a reasonable company should try to help the people that use its services."

Legal experts say the Los Angeles trial is a bellwether, since juror findings could influence thousands of related cases and how platforms design products; nevertheless, the court must decide whether design choices were a substantial factor for the plaintiff’s harms, not merely one of many influences. If jurors find for the plaintiff, companies may face new legal risks and pressure to redesign features that encourage prolonged use.