Users of Facebook can "Like" pages, a vote of approval that can help expose a company's brand to a user's friends and build momentum around advertising campaigns.

Despite Facebook's closed network that requires users to register using their real identity, the social network is still gamed: users can be tricked into liking something, malicious software can be used to infiltrate accounts and other scammers have set up businesses selling "Likes" in bulk in violation of Facebook's terms of service.

The comes as Facebook is under intense pressure to prove itself as a powerful and profitable digital advertising platform. Facebook said it has always had systems to eliminate fraud, but that it has now "increased our automated efforts."

"A Like that doesn't come from someone truly interested in connecting with a page benefits no one," the company said. "Real identity, for both users and brands on Facebook, is important to not only Facebook's mission of helping the world share, but also the need for people and customers to authentically connect to the pages they care about."

Facebook sought to reassure users, saying that less than 1 percent of Likes will be removed on average from a page.