Amazon.com has resumed its efforts to merge duplicate ASINs for book titles. ASINs are "Amazon Standard Identification Numbers" used to identify a particular item. Sellers are allowed to create new ASINs in books and certain other categories. After Amazon told users on November 12, 2007, that it would begin cleaning up duplicate ASINs, sellers expressed concerns about the timing of the new initiative and whether it could lead to order mix-ups. On November 16, Amazon told sellers it would delay the initiative until it could provide a thorough explanation of the program with examples and a FAQ.
On December 6, Amazon.com announced that the initiative was proceeding as planned, and published FAQs. While Amazon will automatically move sellers' merged ASIN listings to the retained ASIN, sellers who attempt to relist on a merged ASIN will be unable to do so. Instead, they must search for the merged ASIN on the Amazon.com website, at which point they will be redirected to the retained ASIN under which they can list their inventory.