James Martin/CNET

A law firm on Monday filed another lawsuit against Facebook for failing to protect consumer data.

The suit, following a similar case last week, was filed in the US District Court for the Northern District of California in San Jose. It accuses Facebook of "unjust enrichment and violation of privacy and consumer-protection laws when it permitted app developers and other third parties to exploit its 'lax to non-existent enforcement practices,'" according to a press release from law firm Hagens Berman.

The firm alleges breach of contract and violation of California's unfair competition law, among other complaints. The suit asks for damages to be awarded to the plaintiffs, as well as injunctive relief "to ensure that Facebook's users are not injured by similar shenanigans again." It wants class action status.

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Facebook reiterated a comment from Paul Grewal, its deputy general counsel. "We are committed to vigorously enforcing our policies to protect people's information," he said in response to last week's lawsuit. "We will take whatever steps are required to see that this happens."

Facebook has been facing the biggest scandal in its 14-year history. Personal info from about 300,000 users was originally collected in 2013 for a personality quiz app called This is Your Digital Life, designed by Aleksandr Kogan, a Cambridge University researcher. Because of how Facebook worked at the time, Kogan was able to access data from friends of the quiz takers -- up to 87 million of them -- and share the information with Cambridge Analytica. The data analytics firm then may have used the data to help the Trump campaign during the 2016 presidential election.

Outcry over the misuse of data has caused Facebook to make changes to its site, including launching a tool to notify users if they were affected by the Cambridge Analytica data scandal. Facebook also announced new privacy settings and a clearer privacy policy and said it's auditing the thousands of apps on its site to make sure it knows how data is being collected.

CEO Mark Zuckerberg is slated to testify before Congress on Tuesday and Wednesday. The US government wants Zuckerberg to explain how so much personal data could have been shared about users, as well as what he's doing to prevent this from happening in the future.

Last week, attorney John Yanchunis of law firm Morgan & Morgan filed a lawsuit against Facebook and requested class action status. That suit alleges the companies violated California's unfair competition law. It seeks damages paid to plaintiff Lauren Price and, as a proposed class action, to others similarly affected.

Monday's lawsuit alleges that "Facebook stood idly by" while an app developer "sucked down the data portfolios of 70 million-plus of its users." It also said that Facebook "made only the weakest attempts to prevent further access to this data."

That complaint initially includes three plaintiffs: Carol Johnson from Novato, California; Daniel Paul of Boulder, Colorado; and Steve Mortillaro of Nashville, Tennessee. They say that Facebook likely shared their data with Cambridge Analytica without their permission.

Hagens Berman is seeking additional people to join its proposed class action suit. It noted that it "has represented millions of consumers in class action cases, recovering more than $200 billion in victories and settlements."

"Facebook has repeatedly failed to uphold its own privacy agreements and policies, and it's brazenly neglected the data security of the billions of those who use its social media service," Steve Berman, managing partner of Hagens Berman, said in a statement. "Instead of choosing to be vigilant, making appropriate investments in data security and stopping this massive harvesting of users' information by third parties, Facebook stood by as the private information of millions was funneled into the hands of bad actors."

Hagens Berman Facebook Users Privacy Lawsuit by jonathan_skillings on Scribd

Update at 7:30 p.m. PT. Adds Facebook comment.

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