rel=ugc
rel="ugc" is a link attribute that identifies links created by user-generated content, such as blog comments, forum posts, and community submissions.
Written as , it was introduced by Google in 2019 to give site owners a more precise alternative to a blanket nofollow link on content they did not write themselves. It tells Google the link came from a visitor, not an editorial decision by the site, so it carries less trust by default.
For link builders, the relevance is twofold. Links you earn in comment sections or forums are commonly tagged ugc and pass little to no link equity, so they are weak for rankings even if useful for referral traffic. On your own site, applying ugc to comment links protects you from being seen as endorsing spam.
Like sponsored and nofollow, Google treats ugc as a hint rather than an absolute directive. Mass-posting ugc links across forums is a recognizable link spam footprint and offers minimal ranking benefit, so prioritize editorial placements instead.