An eight-year Facebook user, Lauren Price, has sued Facebook and Cambridge Analytica over the firm's gathering of private data about more than 50 million people through the social network.

The suit, filed Tuesday in US District Court in San Jose, alleges the companies violated California's unfair competition law. It seeks damages paid to Price and, as a proposed class action, to others similarly affected.

Attorney John Yanchunis of law firm Morgan & Morgan, who also has worked on class actions involving Experian and Target data breaches, filed the suit. It's up to a judge to determine whether it's certified as a class action that could mean many other Facebook users could join the case. (See below for a full look at the suit.)

"This case involves the absolute disregard with which defendants [Facebook and Cambridge Analytica] have chosen to treat plaintiff's personal information. While this information was supposed to be protected, and used for only expressly disclosed and limited purposes, CA, without authorization... improperly collected the Personal Information of nearly 50 million Facebook users. Facebook, for its part, knew this improper data aggregation was occurring and failed to stop it," the lawsuit said. "Facebook's 'trust model' was rife with security vulnerabilities and a near total abnegation of its responsibility to audit its own rules limiting use of Facebook data by third parties."

The Facebook-Cambridge Analytica case joins countless data breaches that reveal just how hard it is to protect our privacy online.

For its part, Facebook points the finger of blame at Cambridge Analytica.

"We are committed to vigorously enforcing our policies to protect people's information. We will take whatever steps are required to see that this happens," Paul Grewal, Facebook's deputy general counsel said in a statement. "When we learned of this violation in 2015, we removed his app from Facebook and demanded certifications" from Cambridge Analytica and business partners Christopher Wylie and Aleksandr Kogan, Grewal said. "Cambridge Analytica, Kogan and Wylie all certified to us that they destroyed the data."

But the suit is another problem for Facebook to handle as it struggles with the privacy scandal. It's also facing a #DeleteFacebook movement urging the 2 billion people who use Facebook to stop, pointed criticism of Chief Executive Mark Zuckerberg and government inquiries about what exactly happened.

Cambridge Analytica didn't immediately respond to a request for comment.

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