Facebook has altered its News Feed algorithm to take into account how long users are likely to spend reading articles.

This means that it will prioritise content not only that the user is more likely to click on, but that they will – according to Facebooks predictions – spend more time reading, either in Instant Article or Facebooks in-app mobile browser. This looks like bad news for clickbait articles that draw users in with a misleading headline, but Facebook says it doesnt anticipate any significant changes beyond minor decreases or increases in referral traffic for some Pages.

“We ask thousands of people to rate their experience every day and tell us how we can improve what they see when they check Facebook — we call this our Feed Quality Program,” said software engineer Moshe Blank and research scientist Jie Xu, in a blog post announcing the change. “From these conversations we have learned that the actions people take on Facebook – liking, clicking, commenting or sharing a post – don’t always tell us the whole story of what is most meaningful to them.”

Facebook doesnt specify how the reading times will be predicted, but seems to based on other users engagement with the same content. It does say that loading times will not count towards this time, and it will be looking at the time spent within a threshold so as not to accidentally treat longer articles preferentially.

Facebook will also be updating the algorithm to reduce how often people see several posts from the same source in a row.

The change will be rolling out over the coming weeks.