A U.S. jury has ruled that the design of major social media platforms can contribute to addictive behavior, delivering a landmark verdict against the companies behind Instagram and YouTube and opening the door to a wave of similar lawsuits.

After nearly nine days of deliberations, a jury in Los Angeles concluded that Meta and Google were responsible for damages suffered by a young woman who argued that the platforms’ design features encouraged compulsive use during her childhood. The jury awarded $3 million in damages, assigning 70 percent of the responsibility to Meta, the owner of Instagram, and 30 percent to Google, which owns YouTube. An additional $3 million in punitive damages was later imposed.

The case was brought by a plaintiff identified in court documents as KGM, now 20 years old. She testified that she began using YouTube at age six and joined Instagram at age nine. According to the lawsuit, she developed extreme patterns of use, at times spending up to 16 hours a day on Instagram. Her legal team argued that the platforms’ design played a significant role in worsening anxiety, depression, body image issues and suicidal thoughts.

Central to the case were claims that social media companies intentionally built features that encourage prolonged engagement, particularly among young users. Lawyers for the plaintiff argued that elements such as endless scrolling feeds and algorithm driven recommendations were designed to keep children online for extended periods because higher engagement increases advertising revenue.

Evidence presented during the trial included internal communications and studies from the companies. According to the plaintiff’s legal team, some internal research suggested that young users experiencing emotional distress were more likely to become deeply engaged with the platform. Jurors were also told that company communications sometimes acknowledged the addictive nature of certain platform features.

Meta and Google disputed those claims. Lawyers for the companies argued that KGM faced personal and family challenges before she began using social media and that it would be inaccurate to attribute long term mental health struggles solely to online platforms. The defense also suggested that social media sometimes provided a form of connection or support during difficult periods in her life.

Executives from the companies testified about recent safety measures designed to protect younger users. They pointed to tools that limit screen time, restrict certain content and allow parents greater oversight. Company representatives also argued that the platforms do not intentionally aim to maximize the amount of time users spend online.

Another central legal question involved Section 230 of the Communications Decency Act, a U.S. law that protects online platforms from liability for user generated content. The companies argued that this protection should apply to the case. However, the judge instructed the jury that the lawsuit focused on platform design rather than the content posted by users. That distinction limited the companies’ reliance on the law.

Legal experts say the verdict could mark a turning point in the growing legal battle over the effects of social media. The case is one of more than 20 similar lawsuits scheduled as early test trials that may shape how courts handle claims about digital addiction.

The ruling also comes days after another jury found Meta liable in a separate case involving allegations that the company concealed information about risks to children on its platforms. Together, the decisions signal increasing scrutiny of how social media products are designed and marketed to young users.

Meta and Google have both indicated they intend to appeal the decision. Still, the outcome may encourage additional lawsuits and possibly class action cases seeking damages related to social media addiction.