Back in 2012, a class-action lawsuit was slapped against Facebook for breaching user privacy - it was alleged that the company tracked users' Internet activity even after they log off. That particular lawsuit has now been dismissed. Passing the verdict, the judge said the plaintiffs failed to explain exactly how they were affected by the tracking, or how it caused them "a realistic economic harm or loss." He, however, gave them another chance, allowing them to refile their claims in a revised lawsuit. It's worth mentioning that the sum of $15 billion was calculated by calling on the Wiretap Act, which - according to the complaint - allows victims (estimated to be around 150 million in this case) to claim damages of as much as $100/violation/day for each Facebook user. Plaintiffs can file the revised lawsuit till November...
Source: http://www.gsmarena.com/us_court_dismisses_15_billion_privacy_lawsuit_against_facebook-news-14669.php