@nprofile1q... One major original purpose of ISBNs is inventory and distribution control. The whole point of an ISBN is that it is unique, AND worldwide, so that it reliably identifies an item with a specific set of traits (title, author, publisher, medium, edition or revision, etc.)Collision avoidance in assigning the numbers is vital. You absolutely do not want to have a system that might assign the same ISBN(equiv) to two different items. They had those before ISBNs were agreed to in the 60s. Thus ISBN