Is nothing private? Facebook tracks which sites 800m users visit... even AFTER they sign off



Facebook is tracking which sites its 800million users visit – even after they have signed out, a new report has revealed.



Company employees are also able to watch where people who are not members of the social-networking site go online, if they have just viewed Facebook once.



Critics have expressed serious concern about the practice and called for tighter regulations to protect internet users' privacy.

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We'll be watching you: Facebook can track which sites users visit even after they log off thanks to plug-ins and cookies

'Facebook could be tracking users without knowledge or permission, which could be an unfair or deceptive business practice,' Representative for Massachusetts Ed Markey told USA Today.



The site has explained for the first time how it uses two types of cookies to log the extensive data in a series of interviews with USA Today.



The tracking means that every time an internet user being followed clicks on to a third-party page which has a Facebook plug-in attached, such as the popular 'Like' widget, a record is sent back to the company.

According to Facebook, the data is used to boost security and improve the quality of the plug-ins and not to gather personal information to promote user-specific ads.



Officials said the sponsored ads found on a user's Facebook page are based on the information provided on the profile and by the choices made when clicking the 'Like' button.



But still, some web observers are worried.



Eyes on me: Critics have called for Facebook founder Mark Zuckerberg, pictured this month, to face tighter internet regulations

'Tracking data can be used to figure out your political bent, religious beliefs, sexuality preferences, health issues or the fact that you're looking for a new job,' Peter Eckersley, projects director at Electronic Frontier Foundation, a digital rights organisation, told USA Today.



'There are all sorts of ways to form wrong judgments about people.'



Here's how it works: Every time you log onto Facebook it inserts a 'session cookie' and a 'browser cookie' into your browser. If you simply visit the site without signing up on the browser cookie is inserted.



From that point on, each time you visit a site which uses Facebook technology, the cookie works in conjunction with the plug-in to alert Facebook to the date, time and URL of the page you are viewing.



The unique characteristics such as your IP address, screen resolution, operating system and browser version, are also recorded, USA Today reported.



Facebook is therefore able to compile a rolling address book of all your webpage visits for 90 days, continually deleting entries for the oldest day and adding the newest.



'Facebook could be tracking users without permission, which could be an unfair business practice,' Representative Ed Markey, pictured, has said

If you are logged-in to your Facebook account and surfing the web, the session cookie records this date meaning your name, email address, friends and all data associated with your profile are also logged.



Arturo Bejar, Facebook's engineering director, acknowledged to USA Today that Facebook could learn where specific members go after they have signed off but denied the company recorded such information.



Mr Bejar told the paper: 'We've said that we don't do it, and we couldn't do it without some form of consent and disclosure.'



That testimony was not enough to appease Ilse Aigner, Germany's minister of consumer protection, who last month banned Facebook plug-ins from government websites and suggested that private companies to follow suit.



While Thilo Weichert, a data protection commissioner in the Germany said: 'Whoever visits Facebook or uses a plug-in must expect that he or she will be tracked by the company for two years. Such profiling infringes German and European data protection law.'



Elsewhere, Arnold Roosendaal, a doctoral candidate at Tilburg University in the Netherlands, and Nik Cubrilovic, an independent Australian researcher, independently wrote about how pages containing Facebook technology carried out tracking on a greater scale than the company publicly admitted to.



Denial: Facebook said it did not use the trackingto record where users go and a spokesman said the company has 'no plans to change how we use this data'

Facebook spokesman Andrew Noyes slammed Germany to USA Today, saying the country does not understand how the tracking technologies work. And he blamed 'software bugs' for the indiscriminate tracking uncovered by Roosendaal and Cubrilovic.



'When we were made aware that certain cookies were sending more information to us than we had intended, we fixed our cookie management system,' Mr Noyes told USA Today.



However, Mr Roosendaal said: 'They have been confronted with the same issue now several times and every time they call it a bug. That's not really contributing to earning trust.'



And Mr Markey, who is behind a bill aimed at limiting online tracking of children, said Facebook 'should be covered by strong privacy safeguards.'



'The massive trove of personal information that Facebook accumulates about its users can have a significant impact on them — now and into the future,' he told USA Today.

Ron Culler, of Secure Designs, told WFMY he is not surprised by this tracking.

'It's just how the internet works. It's how targeting advertising is done for the big ad sites like Yahoo and Google,' he said. 'Facebook wants to know who's going to their sites, who's using their 'Like' buttons and link buttons and things like that.'



But Mr Noyes said that the company has 'no plans to change how we use this data.'