Many e-tailers have looked with envy at Amazon.com’s sheer omnipresence within the search results on Google. Search for any product ranging from new book titles , to new music releases , to home improvement products , to even products from their new grocery line , and you’ll find Amazon links garnering page 1 or 2 rankings on Google and other engines. Why does it seem like such an unfair advantage?
Can you keep a secret? There is an unfair advantage. Amazon is applying conditional 301 URL redirects through their massive affiliate marketing program.
Most online merchants outsource the management and administration of their affiliate program to a provider who tracks all affiliate activity, using special tracking URLs. These URLs typically break the link association between affiliate and merchant site pages. As a result, most natural search traffic comes from brand related keywords, as opposed to long tail keywords. Most merchants can only imagine the sudden natural search boost they’d get from their tens of thousands of existing affiliate sites deeply linking to their website pages with great anchor text. But not Amazon!
Amazon’s affiliate (“associate”) program is fully integrated into the website. So the URL that you get by clicking from Guy Kawasaki’s blog for example to buy one of his favorite books  from Amazon doesn’t route you through a third party tracking URL, as would be the case with most merchant affilate programs. Instead, you’ll find it links to an Amazon.com URL (to be precise: http://www.amazon.com/exec/obidos/ASIN/0060521996/guykawasakico-20), with the notable associate’s name at the end of the URL so Guy can earn his commission.
However, refresh that page with your browser’s Googlebot User Agent detection turned on, and you’ll see what Googlebot (and others) get when they request that same URL: http://www.amazon.com/Innovators-Dilemma-Revolutionary-Business-Essentials/dp/0060521996 delivered via a 301 redirect script. That’s the same URL that shows up in Google when you search for this book title .
So if you are a human coming in from affiliate land, you get one URL used to track your referrer’s commission. If you are a bot visiting this URL, you are told these URLs now redirect to the keyword URLs. In this way, Amazon is able to have its cake and eat it too – provide an owned and operated affiliate management system while harvesting the PageRank from millions of deep affiliate backlinks to maximize their ranking visibility in your long tail search query.
(Note I’ve abstained from hyperlinking these URLs so bots crawling this content do not further entrench Amazon’s ranking on these URLs, although they are already #4 in the query above!).
So is this strategy ethical? Conditional redirects are a no-no because it sends mixed signals to the engine – is the URL permanently moved or not? If it is, but only for bots, then you are crossing the SEO line. But in Amazon’s case it appears searchers as well as general site users also get the keyword URL, so it is merely the affiliate users that get an “old” URL. If that’s the case across the board, it would be difficult to argue Amazon is abusing this concept, but rather have cleverly engineered a solution to a visibility problem that other merchants would replicate if they could. In fact, from a searcher perspective, were it not for Amazon, many long tail product queries consumers conduct would return zero recognizable retail brands to buy from, with all due respect to PriceGrabber, DealTime, BizRate, NexTag, and eBay.
As a result of this long tail strategy, I’d speculate that Amazon’s natural search keyword traffic distribution looks more like 40/60 brand to non-brand, rather than the typical 80/20 or 90/10 distribution curve most merchants (who lack affiliate search benefits) receive.