Facebook has been ordered to limit the amount of information it gathers on its users as the backlash against the social media giant continues.
A German court has ruled that Facebook will need to cut down on collecting user data across different platforms unless customers have given explicit consent.
The ruling from the German competition regulator (FCO) comes after the body declared it believes Facebook took advantage of its market dominance to gather up huge amounts of user data.
Facebook data collection
"In future, Facebook will no longer be allowed to force its users to agree to the practically unrestricted collection and assigning of non-Facebook data to their Facebook user accounts," said FCO president Andreas Mundt.
"The combination of data sources substantially contributed to the fact that Facebook was able to build a unique database for each individual user and thus to gain market power."
The ruling will apply not just on Facebook, but across WhatsApp and Instagram - both of which are owned by the company, and will soon be integrated by Facebook to share messaging services.
The FCO has said that the different platforms can continue to collect data, but this will need to be kept separate from other services unless the user gives their permission.
In a similar vein, Facebook will only be allowed to collate data from third-party websites and link it to a user's account only if they have given consent.
On the company's main site, this could mean that Facebook will need to amend its Like and Share buttons, both of which allow the firm to track a users IP address, web browser type and version, as well as other data that allows Facebook to identify a user personally.
The ruling is only applicable in Germany for now, but with Facebook currently under investigation in several other countries, could influence its future activities across the world.
Failing to abide by the ruling could see Facebook fined up to 10 percent of its annual revenues.
Facebook hit back at the ruling in a blog post, noting that collecting such data allows it to display better targeted ads to its users, as well as making it easier to identify fake and harmful accounts.
"The GDPR specifically empowers data protection regulators - not competition authorities - to determine whether companies have lived up to their responsibilities," it said.
"And data protection regulators certainly have the expertise to make those conclusions."
"The [FCO] order threatens to undermine this, providing different rights to people based on the size of the companies they do business with."
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