There is raging debate in the writing world about assigning ISBNs to ebooks. Some say an ebook doesn’t need an ISBN. Others say it does. As someone about to publish an ebook, I needed to know.
I had a second question. There are two formats for ebooks: Mobi (Kindle) and Epub (Nook, and everyone else). To fully cover the ebook market, I need both versions available. If an ebook needs an ISBN, would I need two, one for each version?
The actual answer is yes, an ebook needs an ISBN, and yes, each version gets its own. Those answers come right from the source, ISBN International, the folks in charge of those things.
According to ISBN International, ISBNs are assigned based on format, not text. A book can have six different formats — hardback, quality paperback, mass market paperback, audiobook, Kindle, and Nook. That means the same book, with no textual changes, has six formats and needs six ISBNs.
The ISBN serves as a library call number. It identifies the book by format and edition. A reader wanting the second edition mass market version does not want the first edition hardback. Hence, why two separate numbers are needed.
There is an exception, and this is why so many writers say the ebook does not need an ISBN. If a book is published through a proprietary platform, and carried by a proprietary market, then it does not need an ISBN. This means Amazon. Kindle, and the Mobi platform, are available only through Amazon. An ebook published through Amazon is assigned its own proprietary number by Amazon itself. It is naturally identified. It is also naturally protected, as far as an ebook can be. So, it won’t necessarily need an ISBN, unless the author chooses to get one for it. The majority of ebook writers publish through Amazon, foregoing Nook. So, they would say no, the ebook doesn’t need one.
I’m picky. I want one for my Kindle books. And as I want to cover Nook and Google and Apple readers, I want Epub versions available (Lulu will handle that). So, every book I publish will receive four separate ISBNs (hardback, paperback, Kindle, and Nook). When I can afford to hire Tara Strong to record an audiobook, that will be a fifth.