In order to cut down on fraudulent "likes" across the network, Facebook has announced that they have upped their automated efforts to remove likes that have been "gained by means that violate [thier] terms."
This means that likes derived from malware, fake accounts, compromised accounts, or bulk purchases will be stricken from the Facebook record.
Why? Integrity, according to Facebook.
"A Like that doesn't come from someone truly interested in connecting with a Page benefits no one. 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. When a Page and fan connect on Facebook, we want to ensure that connection involves a real person interested in hearing from a specific Page and engaging with that brand’s content.
Facebook was built on the principle of real identity and we want this same authenticity to extend to Pages," they say in a Security note.
So, will this mean that your page will suddenly drop a significant amount of likes overnight? Not likely. Facebook says that the improved efforts will only result in less than 1% of total likes being removed.