Google has forever affected SEO with their creation of the rel= “nofollow” attribute on hyperlinks. Google was afraid that their ranking algorithm was being manipulated from advertising and comment spam. Hence the creation of the nofollow.

When a nofollow is placed on a hyperlink, it tells the search engine that it should not influence the link target’s ranking in the search engine’s index.

The nofollow attribute differs from using the Robots.txt.

How the attribute is being interpreted differs between the search engines. While some take it literally and do not follow the link to the page being linked to, others still “follow” the link to find new web pages for indexing. In the latter case rel=”nofollow” actually tells a search engine “Don’t score this link” rather than “Don’t follow this link.” This differs from the meaning of nofollow as used by robots meta tag, which does tell a search engine: “Do not follow any of the hyperlinks in the body of this document.” - Wikipedia

Ways to use the Nofollow

1) To prevent “comment spam” on blogs. The nofollow certainly has it’s place. Some people say to automatically nofollow links in comments. But, if the link and commenter adds to the conversation, why not reward them with a link?

2) Using Nofollow to control internal PageRank flow. Any experienced SEO Consultant has learned the best way to use the nofollow to their benefit. It’s called, PageRank scultping. In a nut shell, links on a page bleed PageRank. So, to strengthen a page’s PageRank without removing any links, all you have to do is nofollow the link. For example, you can nofollow pages like “Term & Conditions”, Privacy Policy, etc. Or, if you have links on a page with generic wording like, “Click Here”, then using the nofollow will cause more PageRank to flow to the hyperlinks that contain keywords.

3) The nofollow has affected Advertising. Specifically, buying & selling links. So now, any website that sells advertising and doesn’t place a nofollow on the link, potentially faces a penalty from Google. But Advertisers don’t want their links to be nofollowed! So, they stop advertising on websites that nofollow. It becomes a catch-22 situation. Bottomline, it’s best to fly under the Google radar. Don’t worry though. There are strategies for both sellers & buyers of links, and still many great ways to conduct link building, and properly structuring a link campaign.

Additional Resources:
Does PageRank Sculpting Work? Yes.
Why There’s Nothing Wrong With Sculpting Your Pagerank.
Sculpting Your PageRank For Maximum SEO Impact.
Nofollow sculpting my take.
PageRank sculpting - Siloing.

Photo Credit: Brian Purkiss

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