Facebook, never exactly a paragon of privacy, has once again been sued by users over allegations of profiting off users’ personal data. This time, the plaintiffs claim that the website is turning links shared in private messages into public “likes,” from which Facebook earns ad revenue.

“Contrary to its representations, ‘private’ Facebook messages are systematically intercepted by the Company in an effort to learn the contents of the users’ communications,” reads the suit, filed in a U.S. District Court in California. “In the course of the last year, independent survey researchers discovered that Facebook reviews the content of its users’ private Facebook messages for purposes unrelated to the facilitation of message transmission.”

Specifically, claims the complaint, when a user sends a link in a Facebook message, Facebook then allegedly “scans the content of the Facebook message, follows the enclosed link, and searches for information to profile the message-sender’s web activity.”

So if you write to your pal Suzy about how much she would love a story on Consumerist and then copy/pasted the URL for that story into the message, the plaintiffs say that Facebook is now building a marketing profile on you based on the the fact that you shared this particular link.

Furthermore, when Facebook follows that link back to the source page, if it finds a “Like” button there, then the company assumes that your sharing of this story counts as a “like” for this content, whether or not you have actually enjoyed this story (perhaps you were sending the Consumerist link to Suzy because you thought it was the worst thing you’ve ever read).

“Representing to users that the content of Facebook messages is ‘private’ creates an especially profitable opportunity for Facebook, because users who believe they are communicating on a service free from surveillance are likely to reveal facts about themselves that they would not reveal had they known the content was being monitored,” contends the lawsuit. “Thus, Facebook has positioned itself to acquire pieces of the users’ profiles that are likely unavailable to other data
aggregators.”

The complaint seeks class-action status on behalf of all Facebook users in the U.S. who have sent links in private messages, which has to be a pretty hefty chunk of the 166 million or so registered Facebook users in the country.

In terms of damages being sought, the complaint asks for $100 for each day of violation or $10,000 per class member, plus statutory damages of either $5,000 per class member or three times the amount of actual damages, whichever is greater.

For its part, Facebook says the allegations are “without merit and we will defend ourselves vigorously.”

Facebook sued for allegedly making private messages into public “likes” [Ars Technica]

Facebook faces suit over data allegations [CNBC/Financial Times]

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