How Facebook Watches You Social media giant tracks your previous 90 days of browsing By Kevin Spak, Newser Staff Posted Nov 16, 2011 2:12 PM CST 8 comments Comments Facebook CEO Mark Zuckerberg talks about the social network site's privacy settings last year. (AP Photo/Marcio Jose Sanchez, File) (Newser) – Facebook is watching you—even if you’re not a Facebook user—but insists it’s less nefarious than rivals who do the same thing. The social networking giant uses tracking cookies to keep a running log of every page users have visited for the past 90 days, engineering director Arturo Bejar tells the USA Today. It also tracks anyone, user or otherwise, who happens onto Facebook for any reason. But the social networking giant says it uses that data only to improve its security and user experience—unlike Google, Microsoft, Yahoo, and loads of smaller companies that use the same technology to target advertisements to users. But not everyone is convinced of Facebook’s intentions—Congressmen Ed Markey and Joe Barton, for instance, sent Zuckerberg a letter asking why Facebook had applied for a patent on a method of correlating tracking data and ads. Facebook’s response? “We patent lots of things,” a spokesman says.