Nofollow

Long definition

Introduced in 2005 to fight comment spam, rel="nofollow" was for 14 years a hard directive: Google would not use the link for PageRank flow nor for anchor-text relevance signals. That changed in September 2019 when Google announced nofollow became a "hint" — Google may choose to respect it or not, based on context.

At the same announcement Google introduced two companions for more semantic precision:

• rel="ugc" — user-generated content (comments, forum posts). Tells Google this isn't editorial.
• rel="sponsored" — paid or affiliate links. Required by Google's guidelines for disclosing compensation.

You can combine them: rel="nofollow sponsored" is common for affiliate links where you also want to discount ranking flow.

Practical consequences of the 2019 shift:

1. Google may use nofollow'd links for discovery even when not passing PageRank. A nofollow link from a high-authority site still helps Google find new URLs.
2. Anchor text from nofollow links may count for relevance context. This was explicitly clarified in Google's announcement.
3. The discount is model-level, not binary. Google likely passes less credit through a nofollow than a regular follow link, but not zero.

Per-page equivalent: <meta name="robots" content="nofollow"> applies the attribute to every link on the page (rarely needed and usually misused; per-link rel="nofollow" is more precise).

Common misconceptions

• "Nofollow links are worthless for SEO." They're valuable for traffic referral (a link on a high-traffic site drives visits regardless of rel), for brand signals, and — post-2019 — for potential anchor-text and discovery credit. Not zero.
• "Using nofollow on internal links sculpts PageRank." "PageRank sculpting" was a 2007-era technique Google patched in 2009. Nofollow internal links still cost you the flow — it just goes to /dev/null instead of the target. Don't do it.
• "Sponsored and nofollow are interchangeable." They're layered. sponsored is about disclosure (Google's guidelines require it for paid). nofollow is about ranking flow. Use sponsored for paid links regardless of whether you also add nofollow.
• "Google still treats nofollow as a hard no-follow." Google explicitly changed this in 2019. The hint model is the current behavior. Content based on the pre-2019 model is outdated.