Facebook's 'Like' button might not appear to be one of the internet's most complex tools, but there's more to the little upturned thumb than meets the eye. Some companies, for instance, use that Like button on their websites as a plugin, and on Monday Europe's top court decided that they are jointly responsible with Facebook for the transfer of people's data.
The court was looking at the case of Fashion ID, a German online clothing retailer, which had the Like button plugin installed on its website. The data of visitors to the website was being transferred back to Facebook without their knowledge, even if they hadn't clicked the button or weren't members of the social network, the court found.
According to the judgment published by the Court of Justice of the European Union, Fashion ID and other websites like it cannot be responsible for what happens to the data after it's passed to Facebook, but they are responsible for "operations involving the collection and disclosure by transmission to Facebook."
The decision means that in the future, all websites transmitting data about European citizens back to Facebook and other social networks -- whether by a Like button or any other plugin -- must first get their explicit permission to do so in order to comply with strict EU data protection rules introduced last year. In accordance with Europe's, people must give explicit consent for their data to be collected.
Companies big and small are, and decisions such as the one made by the Court of Justice on Monday help clarify their roles when the lines are blurred. For Facebook and other social media companies, the judgment provides a clearer idea of which data collection and processing responsibilities are theirs alone, and which are shared by third parties.
"We welcome the clarity that today's decision brings to both websites and providers of plugins and similar tools," said Jack Gilbert, associate general counsel for Facebook. "We are carefully reviewing the court's decision and will work closely with our partners to ensure they can continue to benefit from our social plugins and other business tools in full compliance with the law."