Facebook has denied allegations that it can track what users are doing online even if they log out of the social network, arguing that it only does so to protect the user’s safety.
The denials follow a study released over the weekend, revealing that when a user logs out of Facebook, rather than deleting its tracking cookies, the site merely modifies them, maintaining account information and other unique tokens that can be used to identify the user.
The study, conducted by Australian technologist Nik Cubrilovic conducted tests which seemed to indicate that Whenever a user visits a web page that contains a Facebook button or widget, thier browser is still sending details of their movements back to Facebook.
“Even if you are logged out, Facebook still knows and can track every page you visit,” Cubrilovic wrote in a blog post.”The only solution is to delete every Facebook cookie in your browser, or to use a separate browser for Facebook interactions.”
Cubrilovic is working on a new unnamed start-up but has previously been involved with large technology blog TechCrunch and online storage company Omnidrive.
He backed up his claims with detailed technical information. His post was picked up by technology news sites around the world.
Safety cookies
However, Facebook has denied the claims and has offered an explanation as to why its cookies behave the way they do.
In response, a Facebook engineer wrote on the ZDNET Blog that the social network’s cookies aren’t used for tracking at all.
Instead they are “used for safety and protection such as identifying spammers and phishers, detecting when somebody unauthorized is trying to access an account, helping you users get back into your account if you get hacked, disabling registration for a under-age users who try to re-register with a different birthdate, powering account security features such as 2nd factor login approvals and notification, and identifying shared computers to discourage the use of “keep me logged in,” engineer Arturo Bejar wrote.
The engineer added that facebook doesn’t use cookies to track users on social plugins to target ads or sell their information to third parties. Instead, they are used to personalize content and protect safety.
