News Courtesy of Yoast.com:
When you add a nofollow tag to a link on your site, you’re basically telling search engines that they shouldn’t count your backlink when ranking that page. Doing this helps you avoid leaking link value to pages that may not be trustworthy, or, in case of affiliate marketing, to your advertiser’s website.
But what if you include several affiliate links in every blog post you publish? While you probably link to relevant products, all these links should still have a nofollow tag. This can easily become a large amount of nofollowed links. Does this have any consequences for the link value of your pages?
Nikola was worried about this and emailed us his question:
I have a nofollow tag on my Amazon affiliate links because in Google’s Webmaster guidelines it’s said that ad links should have this tag. But I’m worried that this will cause a drop in link value of my pages as I add these links to almost all of my posts. What should I do? Do Amazon affiliate links hurt blog SEO?
Adding a nofollow tag to Amazon affiliate links
“No, they don’t hurt blog SEO. Nofollow doesn’t hurt anything. If it’s an ad it deserves a nofollow and you’re doing it perfectly right and you shouldn’t change anything. Good luck.”
Ryan’s Take 
I really don’t understand the obsession with discrediting links with nofollow. I don’t think I’ve ever placed a nofollow link on this site and any of its blog posts. Perhaps, it’s ignorant on my part. However, I take the definition of nofollow at face value. It tells Google and other search engines that you don’t vouch for that link. So what is the point really?
If I’m placing a link on my website it is usually to reference a source. Of course, I’ll vouch for that link! Maybe if I were selling banner ads and linking to companies that were paying for advertisement. My worry would then be getting a possible penalty. Although, I think it would have to be a pretty substantial amount of links to get a penalty.
It seems like most SEO agencies and consultants worry about leaking PageRank and influence on a client’s domain in regards to outbound links. The more follow outbound links on a website, the less PageRank, and in turn ranking power that website will have. I think that notion is overblown too. If you’re using hyperlinks for reference purposes why would that cause a penalty? Now, if you had a thousand hyperlinks stacked on top of each other, I could understand. But a few links within meaningful content? Just doesn’t make sense to worry about that.
The Current State of Nofollow
I did see this post quoting a Google Search Analyst stating that nofollow has NOT changed. Maybe that is true, but he didn’t outright say that all nofollow links provide zero SEO value. I’ve see several instances where a backlink profile of a company was very small but had some keywords with high rankings. Several of the nofollow links in those profiles were from high authority websites. How are they able to rank so well?
Then there is a recent post from SEO guru Adam White and his opinion on nofollow links. He actually performed a case study with some interesting results for a no follow link with optimized anchor text. These results showed a dramatic increase in ranking for that keyword (backlink software) after that link was placed. It could be a direct or indirect result. Maybe a lot of people were clicking on that link and the click-thru-ratio for that phrase was causing the jump.
My point is that nofollow links shouldn’t be looked down upon. Yes, you’ll still want to have a backlink profile with about 70% follow links. However, if you can get a nofollow link from a high authority website, go for it! Also, don’t abuse the nofollow link on your own website. Unless you’re doing an advertisement, don’t worry about putting the nofollow tag on links to external websites. Besides, haven’t they earned that credit if you citing them?
What about Amazon Affiliate Links?
That question is a little more difficult to answer. Amazon certainly isn’t going to suffer if you put nofollow links to their products. Does Google think you don’t trust these links by doing just that? I don’t believe it matters one way or another. How many millions of links point to Amazon throughout the internet? It’s more than likely that Amazon is treated like royalty by Google and however you are linking to them is inconsequential.
Back to the leaking rank topic, I still think it is nothing to worry about. Context should be everything. If you’re describing a product with a hyperlink in the content than you should be fine. Maybe if you have a button hyperlink nofollow would be appropriate. However, I would be shocked if rankings were to suffer due to natural “do-follow” linking. In fact, Google’s Matt Cutts talked about no following affiliate links way back in 2012. He confirmed that they are quite aware of “The Big Players” in affiliate marketing as shown in the video here: https://www.youtube.com/watch?v=31BA0rwnfk8
I want to add the no follow to my amazon product links and can’t get an answer as to where to put them. The links I have are iscript not a href so I am not sure where to place the no follow. Everyone that I have asked has recommended I put them in, but where? Amazon help desk say they don’t know what I am talking about and WordPress said you can’t add them on iscript html. HELP!!
Sorry, I’m not familiar with iscript. Are you using some sort of plugin? If you’re not putting the links in manually you’ll probably have to edit some template file codes. If it were PHP I could probably help.
The easiest way to make sure your links are all marked as nofollow is to add a plugin
such as “No Follow All External Links” which is the one I use. You can easily find it in
the plugin directory.
This is my thinking as Google in its help pages about linking only says PAID ad links should have a sponsored or nofollow. That makes sense if you’re paid for placement. But with affiliate marketing, you’re actually picking and choosing what you want to promote, right? You’re not being paid for the LINK, you’re being paid if your link ends up with a sale. That’s a little different than a sponsored link. Just like people mistakenly using branded content tool on Facebook for affiliate links. Affiliate links are not sponsored content. We don’t get paid to promote them, except by… Read more »
Some plugins I use have the no-follow attribute built into their code for outbound product links. I honestly don’t think it matters either way for big sites like Amazon. The theory used to be that each outbound link steals a little bit of your website’s authority which would result in decreased rankings. Perhaps that was true at some point. Now? I doubt that is the case. Google likes to see links of relevance. They won’t punish you for that. I’m constantly linking to other websites that back up a topic or subject I’m writing about. You’ll see this in guest… Read more »
The answer was to the point and given at the beginning. Nice!