by Steve Weber #114, 18 February 2008

When I started selling books on Amazon eight years ago, I couldn't list about one-third of my books. The reason? They were out of print, had no ISBN, and hadn't been added to Amazon's catalog. A few years later, Amazon began allow Pro-Merchants to create catalog detail pages. Suddenly, those old books were fair game. Sellers began creating new detail pages like crazy. This was great for buyers, who could now shop for many more niche books on Amazon. It was a good deal for Amazon, too. Sellers donated their time creating catalog pages, in many cases strengthening the accuracy and depth of Amazon's catalog.

But like any powerful tool, the catalog-creation privilege was misused, too. Many bogus listings were created, sometimes by accident and other times by sellers hoping to catch a sale at an above-market price. So like many good things, the freedom to create detail pages eventually got out of hand. Some sellers created their own listings for books that were already in Amazon's catalog in a bid to fetch a higher price from a buyer who happened to land on the wrong page. In other cases, duplicate catalog pages resulted when sellers bulk-uploaded lists of titles using BASIN matching software.

As a result, a single edition of a book might have had 15 different detail pages on Amazon. Buyers didn't know what to think. Some sellers were compelled to list their books on each of the catalog pages to ensure every possible sale.

In November 2006 Amazon began fiddling with some catalog maintenance to clean up duplicate listings. Amazon merged some duplicate ASINs and inadvertently caused many listings to be closed. This project resulted in the deletion of many Amazon.com listings for books published in England that appeared on Amazon.co.uk. Now, when U.S. sellers tried to create pages for those listings, Amazon's site declared that these books are "ineligible" for listing on Amazon.com. In some cases, the books being declared ineligible for Amazon's US site weren't actually UK editions but had merely been listed for sale on Amazon's UK site. And recently this problem has expanded to Amazon's other international sites. For example, the other day an American seller was unable to list a U.S.-published book on Amazon.com because someone in Canada had already listed the same book for sale at Amazon.ca.

More recently, in November 2007 Amazon really cracked down and began "merging" ASINs when duplicates were detected by Amazon's software. Amazon's intention was to merge book ASINs when it detected duplicate listings for the same title, contributors, binding, publisher, publication date, edition and volume. The result was that all merchant product data, images, and listings for the deleted ASIN were transferred over to the "retained" ASIN. Amazon's strategy was to retain ASINs that had the highest Amazon Sales Rank and more merchants using it.

Here's how all this affects bulk uploads: If a listing in your upload file contains an ASIN that Amazon has merged to a new ASIN, Amazon assigns the listing to the new "retained" ASIN. A warning is reported in the upload's processing report, with the new ASIN identified. Thank goodness, Amazon left intact the sellers' SKUs and Listing IDs for the merged ASINs. Sellers are supposed to verify that the new ASIN correctly identifies the book they're offering.