What is Private Blog Network (PBN)?
Sites controlled by one party purely to sell or pass links. Footprint detection (hosting, themes, ownership, link overlap) makes PBNs a recurring manual-action source.
Related terms
Link Spam
Manipulative linking at scale: paid posts without disclosure, PBNs, injections, automated comments. Detection (SpamBrain and manual review) targets patterns, so one tactic’s death never saves the strategy.
Toxic Backlink
A link from spammy, hacked, or manipulative neighborhoods that risks association harm. Audit the pattern (site-wide footers, PBNs, injections) before reaching for the disavow file.
Manual Action
A human reviewer penalty suppressing a site or pages until fixed and reconsidered. Check the Search Console report first whenever traffic collapses overnight without an update correlation.
Off-Page SEO
Everything that builds a site’s reputation elsewhere: backlinks, mentions, reviews, and digital PR. Off-page signals validate what on-page content claims about expertise.
Referring Domain
A unique site linking to you. Domain diversity matters more than raw link counts: 100 links from one site look like one relationship, not 100 votes.
Link Equity
The ranking value passed through a link, shaped by the source’s authority, relevance, and number of outbound links. Internal links distribute equity; external links earn it.