But a report from Politico suggests that Facebook is holding back information that could help fact-checkers do their jobs more efficiently. All of the data the company has collected on the effects of its fact-checking efforts and fake news flagging hasn't been shared with those doing the fact-checking -- groups like Snopes, FactCheck.org and PolitiFact.

Some of the information these groups are seeking include how often copycat articles appear after one article is flagged as fake, which articles have already been checked by other fact-checkers and if certain stories should be prioritized more heavily. Information that helps fact-checkers choose which articles to tackle would also be beneficial. The executive director of Politifact, Aaron Sharockman, told Politico that one fact-check could take up to five hours so knowing which stories to pick is important. "There's 1,200, 1,500 stories that we could look at today, and we're going to look at two," he said.

Facebook has said that the efforts are working, but hasn't provided any numbers to back that up. Facebook's News Feed product manager, Sara Su, told Politico that the company does plan on sharing this information with fact-checkers eventually but that protecting user privacy is also a concern. "We want to be as transparent as we can be while also respecting the privacy of people on our platform," said Su.

We've reached out to Facebook for comment and we'll update this post if we receive any additional information.