Its a very good question from my point of view and I would like to remove some general myth which is believed to be true among most webmasters across the globe. Myth no-follow links won’t be noticed or taken in to consideration as a back link or inbound links to your site.

But This assumption is wrong, just like Noah noticed that Google do find links some sources which are no-follow in nature and take them in to consideration as a valid external link to your site. Google takes lots of things in to consideration while ranking your pages and also while find an external link to your site and we know about some of them as a webmaster or as a SEO professional and there are lots of things which we don’t know, which Google keeps confidential as it doesn’t want people to exploit some loop holes in their ranking algorithm.

So what I am going to tell now is only based on my own experience and what I have noticed over couple of years of experience in SEO field. So you are free to believe whatever you think is right from your side, I am not forcing anyone to believe what I assume is true because I am stating this out of my own experience and I am not an inside man from Google who knows about all the metrics and algorithms that Google secretly uses to rank and find links.

Google has decided to put on a no-follow and do-follow restrictions to links from a site because it was abused by many webmasters in the early days to get more links to their sites and also to rank high in search engines and it has proved to be of great help for them to reduce spams. Secondly Google also said that no-follow tagged links will not pass any page rank to the linking page and also when the link from your site which is practically no-follow in nature it means you are not giving any authority to those links, if a link from your page gets to a Viagra site whose links are no-follow then it means Google will not consider your site to be a spammy site because it leads to a spammy website, because you are not taking any responsibility to those links and you are not giving any authority to those links too.

But on the other hand all these factors taken in to consideration, it doesn’t mean Google don’t notice those links and look in to them. Its very clear from what me and Noah noticed in webmaster tools that Google notices those links and consider them as a inbound link to your site.

So how it is possible?
I really think Google takes the freedom to even look in to links which are no-follow in nature and notice the anchor text in the link, notices topical relevancy of the linking page to that anchor text, topical relevancy of page content to the anchor text, also topical relevancy of the linking page and also it notices how many people are redirected or clicked through those links and entered your pages on an average in to consideration and value them as a valid inbound link to your site.

Normally we tend to think that no-follow links are not in anyway going to help and its almost equal to no links at all but this assumption is wrong, if Google still finds those links satisfy some set of conditions they take those links in to consideration. But our wrong assumption is just what Google needs because it would have proven them to reduce spams to a great extent. So if you are a link builder just know that no-follow links still do have some juice left in it and if you know how to extract it then bonus credits to you.

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