This is usually a good sign that they do not use PBN or SEO, because there are also many sites using this method, even if they do not use private blog network or SEO techniques. One of the reasons why they do not use PBN or SEO is because they feel that it would be too complicated for them.
However, one way to get confirmation whether they use PBN or SEO is to visit the websites that they own and check out the content. There should be links leading to the main domain of the website.
Also, you can check how many backlinks the website has, because if it has a low amount of backlinks, they might be using a PBN or low SEO techniques. When you get backlinks, it means that the website owner has invested some time and money into it.
Another way to check if they use PBN or SEO is to go to a search engine and do a search for keywords that you think they might use such as PBN or SEO. When you do this, you will get more than 100 pages returned that have PBN or SEO as a keyword and on top of it you will get a lot of links pointing to their websites.
In some cases, these backlinks may have been purchased by someone who has a vested interest in the website and in the traffic that the website has. So if you are interested in doing an SEO analysis, you can purchase the traffic and then you can get these backlinks for free.
You can also take the traffic that is generated by the websites that use PBN or SEO and analyze it in Google analytics to see how the traffic flows. Then you can get another list of backlinks and analyze the traffic.
This will make sure that you have all the information and you can perform the analysis yourself and compare the graphs to see which sites are driving the traffic. Usually, the websites that have good backlinks are the ones that have high traffic and these traffic sources are usually the PBN or low SEO techniques.
In case you are really interested in knowing how to check if a website uses PBN or SEO, the best way is to take the traffic and use it to check the backlinks. Then you can check the traffic to a specific link that has a lot of backlinks on it.
If the traffic is low, then you can simply eliminate this link from your analysis and move on to the next one. You can then repeat this process for all the backlinks that you have analyzed in Google analytics and get a good idea of what the websites that use PBN or SEO are up to.
The difference between PBN and SEO is that websites that use PBN will use simple, low-cost techniques such as blog commenting or private blog network. You cannot expect to use high-priced SEO techniques like link building or pay per click for that matter.
Now you know how to check if a website uses PBN or SEO, you will be able to make better decisions. Do not be afraid to ask the question, if they do not have a website on the main search engines, ask them how they are achieving rankings and find out if they use PBN or SEO.