We study how anonymity affects fake-news sharing on social media using a natural experiment on Flashback, a large Swedish online discussion forum. In 2014, journalists obtained information that allowed them to identify users registered before March 2007, sharply increasing these users’ risk of public exposure while leaving later registrants unaffected.
Using a difference-in-differences design on 1.98 million posts, we find that exposed users reduce references to fake-news sites by about one-quarter of the mean. The effect is concentrated in immigration and domestic-politics discussions and does not extend to legitimate news sources, suggesting that accountability reduces misinformation without reducing news sharing more broadly.
