Monday, February 14, 2011

Clarification of Needing an ISBN

Angie Benedetti brought up a good question on Friday's comments that definitely needed some clarification.

My original statement:  Also, different e-book formats are supposed to have their own individual ISBNs.

Angie asked:  What do you mean by format here? My first thought is PDF vs. ePUB vs. MOBI vs. whatever else, but I know that's not how the publishers do it. Help? :)

My answer in the comments, plus some additional clarifications:

You are NOT supposed to use the same ISBN for MOBI as you do for ePUB, or PDF, et. al.

Do some publishers do it? Yes. Are they supposed to? No. Since many e-publishers only sell digital version from their own websites, not through third-party retailers, it's pretty much a non-issue.

Using George W. Bush's Decision Points as an example, check out and Amazon does use the same ISBN for the Kindle version as the hardcover version, but they also make a point of stating the ISBN is from source pages (i.e. the hardback) and attach an ASIN (which stands for Amazon Standard Identification Number). The ASIN is an internal number used only by Amazon because they're assuming their MOBI e-books won't be read on anything but a Kindle. They also assume the MOBI version won't be available for sale anywhere else, even though Smashwords does sell MOBI versions of e-books.  For the record, Decision Points by George W. Bush is not sold on Smashwords.

Again, the lack of ISBN goes back to Amazon and Smashwords not requiring ISBNs to sell directly from their websites.

However, Barnes and Noble shows a separate ISBN for the ePUB version than either the hardback, the paperback, or the audio book versions of Decision Points. But again, Barnes and Noble only sells the ePUB version, as does Apple iBooks. There's an assumption that they will both be selling the ePUB version as retailers, which is why they both require ISBNs.

All of this hinges on whether or not you're going to sell the same digital format of your ebook through multiple retailers.  The ISBN is a retail record-keeping device, just like a UPC (universal product code).

Also, instead of buying your own ISBNs directly from Bowker, you can buy them from certain retailer/distributors like Smashwords and Lulu.  Yes, buying from a third party is cheaper because they buy ISBNs in larger bulk quantites.  But the way ISBNs are coded, if you use the third-party route to buy your ISBN, it looks like the third-party is the publisher of record.

Since I'm acting as my own publisher, I'd prefer to play it safe--buy my own ISBN blocks and have different ISBNs for different digital versions since I'm going through different retail outlets. For example, I plan to sell my e-books' MOBI version through both Amazon and Smashwords ans well as the ePUB version through Barnes and Noble by myself and iBooks by way of Smashwords, therefore I will have different ISBNs for the MOBI and ePUB versions.  I'm also looking at the possibility of more e-retailers opening down the road as e-books gain more traction in the market.  Individual ISBNs will make it easier to track which e-version sales are doing better.

I admit it's a combination of control issues and old attorney habits rearing their heads--an ounce of prevention, yada, yada, yada. . .

If I was only selling my ebooks through my website, I wouldn't bother with the ISBNs.  I'd save my money for other things, like venti peppermint mochas from Starbucks.  *grin*

Does anyone else have questions? If I don't know the answer, I'll try to find out for you.


  1. Huh, I didn't know that. My publisher sells all the formats they offer (five now, I think) in a ZIPped bundle. I only ever unzip the PDF files, but I'm pretty sure they all have the same ISBN. Fictionwise sells multiple formats, as does Rainbow, and I think ARe, and I'm pretty sure they all have the same ISBN too. I guess most of the smaller publishers and vendors don't know and/or don't care that they're all supposed to be separate. And figure, even if you're buying the cheaper blocks of a thousand ISBNs at a time, using separate numbers for all five versions of each e-book is going to significantly increase your costs in that area.

    I'll keep this in mind when/if I ever start self-pubbing, though; thanks for the explanation.


  2. Glad the breakdown helped, Angie. I haven't found an e-publisher who sells the e-version of their books through a third party retailer. So the whole ISBN thing is moot for them. That may change; it may not. No one, not even me, can say for sure how everything in publishing will shake out.