By Erich Schwartzel, Meghan Bobrowsky, Katherine Sayre and Erin Mulvaney

LOS ANGELES -- A 20-year-old woman prevailed in a landmark social-media trial against Meta Platforms and Google's YouTube in which the companies were accused of designing their apps to be addictive and harmful to adolescents.

A jury found Instagram's owner Meta and YouTube negligent for operating a product that harmed kids and teens and failed to warn about those dangers. The decision dealt a blow to the companies that have historically been shielded by Section 230 of the Communications Decency Act.

The jury ordered the companies to pay $3 million to the plaintiff, a 20-year-old woman named Kaley G.M., who testified that social-media use that started before she was a teenager had dominated her life for years had contributed to mental health issues including anxiety, depression and body dysmorphia. Meta was ordered to pay 70% of the damages, and YouTube to pay 30%.

The jury also determined that additional punitive damages, which are meant to punish the companies, were warranted. Separate proceedings will take place on that award, which could significantly increase the amount the companies have to pay.

A Meta spokeswoman said in a statement, "We respectfully disagree with the verdict and are evaluating our legal options." YouTube didn't immediately respond to a request for comment.

Kaley's lawyers said in a statement that Wednesday's "verdict is bigger than one case."

"For years, social media companies have profited from targeting children while concealing their addictive and dangerous design features," the lawyers' statement said. "Today's verdict is a referendum -- from a jury, to an entire industry -- that accountability has arrived."

The watershed verdict is the second time this week that the companies have rendered the companies liable for harm inflicted by their platforms in court. More than 3,000 other similar lawsuits against Meta, YouTube, Snapchat and TikTok that are pending in California courts.

A jury in New Mexico found Meta liable for failing to protect young people from online dangers, including sexually explicit content, solicitation and human trafficking, on Tuesday in the first trial of its kind and ordered the company to pay a $375 million penalty. Meta said it respectfully disagreed with the jury and would appeal the ruling.

During the Los Angeles trial, jurors heard from Meta executives Mark Zuckerberg and Adam Mosseri and the plaintiff, a 20-year-old woman named Kaley G.M. During closing arguments a week and a half ago, Mark Lanier, an attorney representing Kaley, compared the companies to a lion preying on a herd of gazelle on the Serengeti. The lion doesn't go after the strongest, he said, "they find the one that they think is weaker, more vulnerable, and that's the one that they get."

"We have social media that takes the vulnerable and goes after them in destructive ways," he said.

By focusing on the design of Meta and YouTube's apps rather than the content posted on them, Kaley's case sought to get around longstanding legal protections, known as Section 230 of the Communications Decency Act of 1996, that have largely shielded social-media companies from being held liable for content on their platforms.

It is a bellwether case for thousands of similar lawsuits in California, which serves as a test of evidence to see how juries reacted. The outcome doesn't bind other cases but could encourage settlements now that both sides have a better sense of how their arguments might play out with jurors.

During the seven-week trial, Kaley testified that she started watching YouTube videos at age 6 and made an Instagram account at age 9. She uploaded more than 200 YouTube videos before she turned 10 and created 15 Instagram accounts before she turned 15, Kaley and her lawyers said.

Lanier, Kaley's lead attorney, said that on one day she spent 16 hours on Instagram.

"I wanted to be on it all the time," she said. "If I wasn't on it, I felt like I was going to miss out on something."

Kaley also told jurors that features of both apps, including push notifications for new likes and comments, gave her "a rush" and drew her back in.

Meanwhile, Meta spent hours in cross examination trying to convince jurors that Kaley's struggles were caused by other factors than social media, including a difficult family life and bullying at school.

Meta lawyer Andrew Stanner said notes from six months of therapy appointments didn't mention social-media addiction or name any social-media apps. Mosseri, the Meta executive tasked with running Instagram, testified that the app wasn't "clinically" addictive and Zuckerberg said his company's goal was to give users something useful, not addict them.

"We used to give teams goals on time spent and we don't do that anymore because I don't think that's the best way to do it," Zuckerberg said when he took the witness stand in the second week of the trial.

On Tuesday evening, Meta introduced a new stock option program for senior executives to motivate them to grow the company at an extremely aggressive pace and reach a $9 trillion-plus valuation.

Write to Erich Schwartzel at erich.schwartzel@wsj.com, Meghan Bobrowsky at meghan.bobrowsky@wsj.com, Katherine Sayre at katherine.sayre@wsj.com and Erin Mulvaney at erin.mulvaney@wsj.com

(END) Dow Jones Newswires

March 25, 2026 13:51 ET (17:51 GMT)

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