Google has been granted a new patent with the name “Determining quality of linked documents”.
The patent appears to have been filed a few years ago so the chances are that it is already in effect.
It gives us a greater insight into how Google judges the influence of a link on the search engine positions of a web page.
Here’s the official patent abstract:
“A ranking component ranks documents, such as web pages or web sites, to obtain a ranking score that defines a quality judgment of the document. The ranking score of a particular document is based on the ranking score of the documents which link to it and based on affiliation among the documents.”
According to the patent description, Google could rank the backlinks to a web page differently based on the relation of the pages to each other. In other words, not all backlinks are treated the same.
For example, links from pages that have the same author might have less influence on the rankings of a web page that have no affiliation with the linked site.
The patent also contains an image that illustrates how various web pages might be related:
How does Google limit the value of a link?
According to the patent, Google might do the following:
- Assign a maximum value to links that come from affiliated pages.
- Assign individual values to links from independent pages.
This means that while three links from an affiliated website might carry more value than a one link, the total value of all links from the affiliated website is limited.
The patent also shows a number of methods that Google can use to determine the affiliation of such web pages:
- Interlinking: websites that are more closely interlinked to each other than the average pages on the websites might be considered to be affiliated.
- Hostnames: web pages that have the same domain name or subdomains that are on the same domain are probably affiliated.
- IP addresses: if the first two or three components of the IP addresses are identical, the web pages might be affiliated.
- Visitors: web pages that share many visitors during the same browsing session can be considered to be affiliated.
What does this mean for your website rankings?
- In a nutshell, try to get backlinks from as many different websites as possible.
- Automated linking schemes probably flag up to Google.
- The quality of the links is more important than the quantity of the links. Dozens of links from one or two sources such a link farms or self generated websites are of less value than a few genuine links from separate sources.
