Background & myths · Knowledge
Where does nofollow come from? A short history
January 2005: Google, Yahoo and MSN jointly introduce rel=“nofollow” – a rare industry alliance, aimed squarely at the comment-spam flood drowning the young blogosphere.
The idea: remove the reward, and the industrial spam economics collapse – links without value inheritance are not worth posting at scale.
Four stations in two decades
Station one, 2005 – the weapon: blogs and forums adopt the attribute wholesale, platforms follow, and paid-link marking soon becomes its second job as search engines tighten guidelines against link selling. Station two, 2009 – the loophole closes: SEOs had discovered “PageRank sculpting”, using nofollow on internal links to steer value flows like plumbing; Google changes the accounting so sculpted value simply evaporates instead of rerouting – the technique dies overnight and survives only as a cautionary tale (it has its own question here). Station three, the blanket era: over the 2010s ever more platforms mark all external links – Wikipedia most famously – until nofollow describes less “I distrust this link” and more “our lawyers distrust everything”; the signal grows blunt from overuse. Station four, 2019/2020 – the reform: Google introduces rel=“ugc” and rel=“sponsored” for the why, and reclassifies the whole family as hints – ranking in September 2019, crawling and indexing from March 2020 – reclaiming the link-graph data the blanket era had buried. The through-line of the story: every station is search engines and site owners renegotiating the same treaty about what a link means – and the current terms (precise labels, hint status, duties for paid links unchanged) are simply that treaty's newest edition, which is exactly the version modern tools implement.
Key facts
- 2005: joint introduction by Google, Yahoo and MSN against comment spam.
- 2009: PageRank sculpting dies – sculpted value evaporates instead of rerouting.
- 2010s: blanket nofollow blunts the signal – whole platforms mark every external link.
- 2019: rel=ugc and rel=sponsored arrive; the family becomes ranking hints.
- 1 March 2020: hint status extends to crawling and indexing.