Facebook Moves to Curtail Fake News on 'Trending' Feature

Facebook Inc. is overhauling its "trending topics" box, part of its effort to curb fake news and expose users to a broader range of information.

Starting Wednesday, Facebook's software will surface only topics that have been covered by a significant number of credible publishers, a move designed to cut back on hoaxes by giving more weight to information sources that have been around longer.

What's more, the topics will no longer be personalized to every Facebook user, which could puncture users' so-called filter bubble and expose them to a variety of different news sources and events.

Facebook has changed its trending feature several times since last spring, after allegations that Facebook contract workers who selected the headlines altered what appeared, for political reasons. In August, Facebook fired the contract workers and opted for a largely software-driven approach. This change, which did away with headlines in favor of hashtags and keywords, quickly led to the appearance of false stories in the box.

After the November U.S. presidential election, employees and outsiders criticized Facebook's laissez-faire attitude toward fake news and its role in creating and enforcing echo chambers, in which like-minded users share and read articles that confirm their beliefs.

Facebook is now doing more to fight fake news, but remains wary of directly deciding what is and isn't true. Last month, it entrusted fact-checking groups to flag certain stories as false, which it then would demote in the news feed.

The steps outlined Wednesday echo that approach. The trending feature is separate from the Facebook news feed and is governed by a different algorithm. The box appears to the right of the Facebook news feed on desktop; on mobile, it appears when a user taps the search bar.

Previously, the trending box would display anything shared widely by Facebook users, regardless of the credibility of the publisher.

Now, Facebook will take into account the "historical engagement" of a particular publisher -- how long a publisher has maintained a presence on the social network -- which it hopes will prevent newer fake news sites from generating traffic through Facebook. The trending algorithm will also factor in how many publishers are reporting on the same topic.

"If just one story or post went viral, it wouldn't make it into the trending as it might previously," said Will Cathcart, a Facebook vice president of product management. "It really takes a mass of publishers writing about the same topic to make the cut."

The trending box now will display topics that are popular in whatever country a user is in, and all users in each country will see the same links.

After these changes, the feature will allow users "to learn about what's going on outside of the friends you talk with and follow on Facebook," Mr. Cathcart added.

Even so, Facebook said it would not rehire the trending topics curators or add more people to vet the topics by hand.

Write to Nathan Olivarez-Giles at Nathan.Olivarez-giles@wsj.com and Deepa Seetharaman at Deepa.Seetharaman@wsj.com