20%-40% of partisan FB “fake news” posts are false

Our analysis of three hyperpartisan right-wing Facebook pages found that 38% of all posts were either a mixture of true and false or mostly false, compared to 19% of posts from three hyperpartisan left-wing pages that were either a mixture of true and false or mostly false. The right-wing pages are among the forces — perhaps as potent as the cable news shows that have gotten far more attention — that helped fuel the rise of Donald Trump. These pages, with names such as Eagle Rising on the right and Occupy Democrats on the left, represent a new and powerful force in American politics and society. Many have quickly grown to be as large as — and often much larger than — mainstream political news pages.

Source: Hyperpartisan Facebook Pages Are Publishing False And Misleading Information At An Alarming Rate – BuzzFeed News

Occupy Democrats has nearly 4 1/2 million “subscribers” on Facebook alone. Eagle Rising has a mere 655,000 page likes.

Look at those numbers – literally millions of people voluntarily subscribe to fake propaganda messaging, and then voluntarily share those fake items on their own FB pages, such that individual posts are exposed to tens of millions of potential “targets”.