Link rel values (nofollow, sponsored, ugc)
Labels on a link that tell search engines it is paid, user-added, or not an editorial endorsement.
See it
What it is
The rel attribute describes the relationship between the current page and a linked page. For search, rel="sponsored" marks ads, sponsorships, and affiliate placements; rel="ugc" marks links added by users in comments or forums; and rel="nofollow" is the catch-all for a link you do not want to endorse. Values are space-separated, so one link can be both ugc and nofollow. Google, Yahoo, and MSN introduced nofollow together in 2005 to defuse blog comment spam; sponsored and ugc arrived in 2019, and all three became hints rather than directives at the same time.
Reach for these values at the boundary between editorial choice and links somebody else paid for or supplied. Leave ordinary editorial links alone. A link you chose because it helps the reader should not receive nofollow merely because it points off-site, while an affiliate link still needs sponsored even when the destination is excellent.
Gotcha: these values are labels for crawlers, not security controls. They do not stop a person opening the URL, hide it from the page, or guarantee that a search engine will ignore the destination. Google treats them as hints for ranking and discovery. Also, noopener and noreferrer solve different browser and privacy problems; neither is a substitute for sponsored, ugc, or nofollow.
Ask AI for it
Audit every HTML <a> element and assign rel values by source. Add rel="sponsored" to paid placements, sponsorships, and affiliate links; add rel="ugc" to links submitted through comments, forums, and profiles; and use rel="nofollow" only for untrusted or unendorsed links that fit neither category. Combine values with spaces when both apply, such as rel="ugc nofollow". Leave normal editorial links unmarked. Separately add rel="noopener" to any target="_blank" link. Return the changed markup plus a table naming the reason for every rel value.