A private blog network, or PBN, is a set of websites owned or controlled by the same person or group, built mainly to link to the sites they want to rank. Operators often buy expired domains that still have backlinks, put thin content on them, and add links to client or money sites. It is a link scheme under Google's spam policies, and PBN links are often sold as a service.
How PBNs work
The operator acquires domains, often expired ones with existing links from real sites, and rebuilds them as blogs. Each site publishes enough content to look alive and includes links to target sites. The network is kept private so the links look independent, using different hosts, themes, registrars and writing styles.
Some operators run their own networks for their sites. Others rent links on them to buyers who may not know where the links come from.
Why it is risky
Google's spam policies cover PBNs under link spam, and the related expired domain abuse policy targets buying expired domains to host low-value content that trades on their past reputation. Google's systems aim to detect and neutralize these links, and manual actions remain possible for the sites they point to and the network itself.
Even when a network goes undetected for a while, the value is fragile. If Google discounts the links, any rankings built on them disappear and the money is gone.
How to spot PBN links
When auditing your own profile, or a vendor's sample links, look for patterns.
- Blogs on varied topics whose posts each link to a commercial site
- Domains whose history shows a different business or organization
- Thin or spun content with little real readership
- Many sites sharing hosting, templates, ownership details or the same outbound targets
Example
A vendor's sample links
An illustrative HR software startup, Rosterwell, asks a link vendor for sample placements. Several are on blogs that cover cooking, crypto and pet care in the same month, each post linking to a different software company with exact-match anchor text. Domain history shows two of them were once local business sites. The pattern points to a PBN, and Rosterwell drops the vendor.
Common mistakes
Believing "undetectable" claims
Vendors sell PBN links on the promise they cannot be found. Detection methods are not public, and nobody outside Google can guarantee anything about them.
Disavowing every small blog
Most small sites linking to you are just small sites. Look for network patterns before acting.
Questions
Generally no; they are a search engine policy violation, not a legal matter. The risk is to rankings and budget.
Not on its own. A company with several genuine properties that link where relevant is normal. A PBN exists mainly to pass links.
