A judge in California has ruled that Facebook can legally track user online behaviour, even when users have logged out of the social media site. The lawsuit came about after unnamed plaintiffs argued that by doing so, the company was violating US federal privacy laws. However, Facebook was told it could continue keeping a detailed record of people's internet history even when they were no longer logged in, as a reasonable expectation of privacy or resulting economic harm or loss could not be proven. One way in which Facebook can track behaviour is through third-party Facebook 'like' buttons, which enable a page to be shared without having to copy and paste its URL. The ruling has once again raised the issue of privacy concerns for users of the social media platform. However, as expected, Facebook has released a statement saying that it is pleased with the court's ruling, whilst also addressing concerns by pointing to its 'opt-out' option within its settings, which was launched in 2014 after a similar case.