A Facebook page
The court ruled that invitation emails from Facebook to people who have not consented to receiving them are a nuisanceREUTERS

Facebook's 'friend finder' has been declared unlawful by Germany's highest court as it deemed it as an advertising harassment that encourages users to market the social media network to their contacts. The court called the tool a deceptive marketing practice and held up earlier convictions by two lower courts in Berlin in 2012 and 2014, which found the social media giant in violation of German laws on data protection and unfair trade practices.

The case was filed by the Federation of German Consumer Organisations in 2010. "Invitation emails from Facebook to people who have not clearly consented to receiving them are an unacceptable nuisance," the court ruling said.

The find-a-friend function of the popular social media network accesses an existing user's email address book and sends invitations to contacts who are not yet its members. This function, according to the ruling, is an intrusive form of marketing that uses data imported by the user. Facebook has also been accused of not informing members in a proper way about how it is using their contacts' data.

In a statement, a spokeswoman for Facebook in Germany said it was waiting to receive the formal decision and would study the findings "to assess any impact on its services". Previously, other social media networks have also been in the dock for their questionable privacy and competition practices.

In 2014, Facebook was met with a class action lawsuit accusing it of violating users' privacy by scanning the content of messages for advertising purposes in a California court. Another privacy lawsuit was filed in Austria in late 2015 where the petitioners argued that Facebook has been violating EU data protection laws for a while now such as tracking of internet users through external websites and the monitoring and analysis of users via big data systems.

In December 2015, European Union officials reached an agreement to implement a digital-privacy law that will restrict companies from using an individual's personal information.