While it may be a joyous day for Facebook over on Wall Street, things aren't looking as peachy in the courtroom as the social network has been hit with a lawsuit to the tune of $15 billion. Levied by law firm Stewarts Law US, the complaint combines 21 individual lawsuits dating back to 2011 into one amended class-action suit where it claims Facebook violated user privacy by purportedly tracking web usage.

The lawsuit was filed in a Federal Court in San Jose, California and cites violation of the US Wiretap Act, the Computer Fraud and Abuse Act and the Stored Communications Act, among others. The US Wiretap Act allocates damages for each user up to $100 per day per violation, or up to $10,000. Specifically, the suit claims that Facebook is tracking users even after they log out of the social network.

"This is not just a damages action, but a groundbreaking digital-privacy rights case that could have wide and significant legal and business implications," David Straite, a Stewarts Law partner told Bloomberg via e-mail.

If this all sounds a bit too familiar, you'd be exactly right. This isn't the first time that someone has sued Facebook on the grounds of web tracking. In October 2011, Mississippi resident Brooke Rutledge filed a virtually identical 17-page suit shortly after 42-year-old Kansas lawyer John Graham did the same thing, just to name a few.

The law firm is additionally investigating if it would be possible to include non-US residents in the class-action suit. As of writing, Facebook has yet to publically comment on the matter.