If you'll recall Mark Zuckerberg and co. came under fire after the elections, with people accusing the tech titan of helping skew the results by allowing election-related fake news to propagate. Zuckerberg strongly denied the accusations, claiming that 99 percent of the content you see on the website is authentic. According to a Gizmodo report, though, the company knew it had a problem with fake news websites and had the tool to block them. Facebook decided not to use that tool, because it would prevent most conservative news sources from showing up on people's News Feeds. The company also denied that allegation.
As for this new development, a company spokesperson told The WSJ:
"While implied, we have updated the policy to explicitly clarify that this applies to fake news. We vigorously enforce our policies and take swift action against sites and apps that are found to be in violation. Our team will continue to closely vet all prospective publishers and monitor existing ones to ensure compliance."