Community Notes

Community Notes is X's crowdsourced fact-checking layer, originally launched as Birdwatch in 2021 and rebranded after Elon Musk's acquisition. The system lets approved contributors propose notes that add context to potentially misleading posts, and other contributors rate those notes for helpfulness.

The distinguishing feature is the rating algorithm. A note only becomes publicly visible when contributors who historically disagree on issues rate it as helpful. The system is designed to filter out partisan piling-on and surface notes that read as fair to people across political lines. The algorithm and contributor data are open source, an unusual choice for a platform feature.

In practice, Community Notes appear under posts ranging from political claims, scientific misinformation, manipulated images, missing context on viral videos, and outdated stats presented as current. The note typically links to sources and explains what's misleading without removing the original post.

For posters, getting a Community Note can be embarrassing, especially for accounts whose credibility is the product. There's no penalty besides the visible note, and the original post stays up. Some accounts wear notes as a badge of resistance; others delete the post.

The system has its critics. Notes can take hours or days to appear, by which time a misleading post may have millions of views unmoderated. Some categories of misinformation never reach consensus across the contributor pool. And the bar of "helpful to people across viewpoints" can mean that obvious misinformation in a partisan area doesn't get noted at all.

Still, it's one of the more interesting moderation experiments on any major platform, and other networks have looked at adopting similar models.