Filed in a federal court in San Jose, California, the "amended consolidated class action complaint" on behalf of Facebook users relates to allegations that the company has been "improperly tracking the internet use of its members even after they logged out of their accounts".
The class action was brought by law firms Stewarts Law US and Bartimus, Frickleton, Robertson & Gorny. It brings together 21 related cases filed in various US states in 2011 and early 2012.
"This is not just a damages action, but a ground-breaking digital privacy rights case that could have wide and significant legal and business implications," said David Straite, a partner at Stewarts Law,
The law firms are citing the US federal Wiretap Act, which allows for statutory damages of up to $10,000 per user, meaning that Facebook could be liable to pay more than $15bn in compensation if the action is successful and extended across the social network's 900m user base.
The class action could also have implications for the company's ability to gather data on its users, which is considered vital for future advertising revenues.
Straite also said that his firm is "evaluating the way" in which non-US residents can be added to the group of plaintiffs in the class action.
Also today, a German data protection official warned Facebook investors that the firm's $38 starting share price is based on business activity that breaches European privacy laws.
Speaking to German daily newspaper Frankfurter Allgemeine Zeitung, regional data protection commissioner Thilo Weichert said that Facebook's business model "will implode" if European privacy regulators succeed in censoring the company's activity as they intend.
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