A California jury found both Instagram owner Meta and Google's parent company Alphabet liable on Wednesday in a lawsuit brought by a 20-year-old woman who alleged that YouTube and Instagram were designed to be addictive to children.

The verdict, reported earlier by Reuters, could have wide ramifications in a host of similar liability cases that have accused tech giants of intentionally creating addictive platforms to hook children as users.

Meta and Google will have to pay $3 million in compensatory damages, to be split between the two tech giants. Meta will pay 70% while Google pays the remaining 30%. There could be additional punitive measures taken as the court continues assessing this case. 

"We respectfully disagree with the verdict and are evaluating our legal options," a Meta spokesperson said in a statement. Google Spokesperson José Castañeda told CNET that the company also disagrees with the verdict and plans to appeal, adding that the case "misunderstands YouTube" as a social media site, instead of a streaming platform.

The trial centered on a 20-year-old woman, known as KGM or Kaley. The case used her experience with Instagram and YouTube when she was young to illustrate allegations that Meta and Google deliberately designed their social media sites to keep young people scrolling. It focused on specific design choices, like recommendation algorithms. She alleged that her social media addiction contributed to her severe body dysmorphia, depression and suicidal thoughts. 

Meta and Google denied those allegations. The jury ruled that the tech companies' negligence played a "substantial factor" in mental health harms. 

TikTok and Snap were part of the original lawsuit but settled with the plaintiff in January, before the case went to trial.

A New Mexico jury on Tuesday imposed penalties totaling hundreds of millions of dollars in a similar case brought by that state. It found that the company allowed child sexual exploitation and misled consumers about the safety of Facebook, Instagram and WhatsApp.

"The era of Big Tech invincibility is over," Sacha Haworth, executive director of The Tech Oversight Project, said in a statement. "After years of gaslighting from companies like Google and Meta, new evidence and testimony have pulled back the curtain and validated the harms young people and parents have been telling the world about for years."

Several high-ranking executives from Meta and Google testified during the trial and pushed back on the idea that social media is addictive, including Meta CEO Mark Zuckerberg and Head of Instagram Adam Mosseri. Mosseri said in February that it was "problematic" to describe social media as clinically addictive. 

Social media platforms have introduced specific settings and tools for their youngest users, such as Instagram's teen accounts, but many of these were launched relatively recently, in the past few years.