An International Standard Book Number (ISBN) is a 13-digit identifier assigned to a specific edition and format of a book. Every format requires its own ISBN: the paperback, the hardcover, the eBook and the audiobook each need a separate number. The ISBN links the book to its publisher of record in the global Books in Print database that bookshops, libraries and distributors use to look up and order titles.
Who owns the ISBN is who is listed as the publisher. If Amazon assigns the ISBN, Amazon is the publisher of record. If you register your own ISBN through Bowker, you or your company is the publisher of record. This distinction affects distribution, credibility and long-term flexibility.
A book using KDP's assigned ISBN cannot be set up on IngramSpark. IngramSpark requires a publisher-owned ISBN because their platform is designed for publishers, not for titles owned by competing platforms. This means a book published only on KDP with Amazon's ISBN is unavailable through bookshop wholesale distribution, library systems and all the retail channels that IngramSpark reaches.
The "Independently published" publisher listing also signals to librarians and bookshop buyers that this is a KDP-only title. Some library systems and academic libraries apply different selection criteria to titles with this publisher listing.
In the United States, ISBNs are sold exclusively through Bowker at myidentifiers.com. A single ISBN costs $125. A block of 10 costs $295, which works out to $29.50 per ISBN and is the right choice for any author publishing multiple formats or planning multiple books. We purchase ISBNs and register them on behalf of every author we publish as part of our standard service. You are listed as the publisher on every title.
