Let me see if I can shed some light on ISBN (International Standard Book Number) because there seems to be a lot of confusion about this relatively straightforward subject.
I've already posted information about ISBN on my FAQ by Joan page on SlingWords. I'll add this post to that information also. (See list of pages at the top of the far right sidebar.)
Most of you probably know that I publish on all the popular platforms so I do know something about which I'm talking.
What Writers Need To Know
The International Standard Book Number or ISBN, as it's popularly called, is a unique numeric commercial book identifier based upon a 9-digit Standard Book Numbering (SBN) code created by Gordon Foster, Emeritus Professor of Statistics, Trinity College, Dublin. The number, which was basically for inventory control, was created in 1966 for booksellers and stationers W.H. Smith as well as others.
From that, a 10-digit ISBN format was developed by the International Organization for Standardization (ISO). That was published in 1970 as ISO 2108. Then, in January 2007, a 13-digit ISBN was created, a format that is compatible with Bookland EAN-13s. (A similar numeric identifier called ISSN, International Standard Serial Number, is used to identify periodical publications.
Sometimes, particularly with self-published books, a book may appear without an ISBN, but this can be corrected if needed at a later date.
In the United States, R.R. Bowker is the Agency of the International Standard Book Numbering Convention, as approved by the International Organization for Standardization.
That means you obtain your ISBN from them whether we're talking a big NY publisher or you, an indie author. Prices for ISBN vary based on how many you buy. If you buy one, it's $125.00. If you buy a block of 10, it's $250.00, a significant savings.
Probably More Than You Want To Know
(Wikipedia defines: "Bookland is a term used to refer to the Unique Country Code (UCC) prefix allocated in the 1980s for EAN identifiers of published books, regardless of country of origin, so that the EAN space can catalog books by ISBN rather than maintaining a redundant parallel numbering system.")
Publishers in other countries obtain ISBNs from their local ISBN Agency. If interested, you can view a directory of these countries on the International ISBN Agency website.
What You Need To Remember
1. Print books cannot be stocked without an ISBN, and some digital bookstores, like Apple, will not stock ebooks without an ISBN.
2. You do NOT need an ISBN for: Kindle, Nook, All Romance eBooks, or Smashwords website sales--meaning no Smashwords Premium catalog distribution.
Amazon and Nook both assign their own Product Number as does Smashwords for
the Smashwords sales site.
3. All Romance eBooks has their own numbering system if you don't have an ISBN. When you register with All Romance, they will assign a specific numbering template just for you then you keep track of the numbers within that system that you use.
4. The only time you need an ISBN is if you want to sell to Sony, Kobo, ScrollMotion, and Apple Bookstores. Most writers do this because they are outlets to which Smashwords distributes. You can use the free ISBN offered by Smashwords to achieve this distribution. That means that Smashwords is then listed as the publisher of your book when it appears for sale at those outlets.
5. If you don't wish to distribute via Smashwords for whatever reason, then you can pay a company to distribute for you. With some retailers like the Apple Bookstores, you simply have to jump through too many loops and pay a rather large fee to distribute to them directly. Some companies like Bookbrewer will provide the ISBN as part of their fee or either as a separate fee (be sure to ask), or you can purchase your own ISBN so that you are listed as the publisher.
6. If you want to purchase an ISBN, you must do so through Bowker since they are the registered company for the U.S. It's easy to set up a publisher account which is what you are if you are an author publishing your own ebooks or print books.
7. Do NOT buy a single ISBN because it's horribly expensive. Buy a block of 10 ISBNs for $250. Twenty-five bucks a pop is reasonable. Chances are you will use all 10 eventually. There's no expiration date on ISBN.
8. A different ISBN is required for each print edition, i.e., hardcover, softcover, etc. Therefore, Bowker holds the same to be true for ebooks in regards to different formats, i.e. .mobi, .epub, .pdf, etc.
9. If you follow Bowker's guidelines to the letter, then you would need to purchase a different ISBN for each electronic format. That's very expensive.
I talked to a rep from Bowker, and I asked questions of friends like Marie Force who bought her own ISBN. I came up with this plan for me.
I'm no expert, but I'd say purchase an ISBN for only one format that can be used at all the distribution outlets that take the same format. That seems to be .epub based on my research, but do your own research first so you'll know for which format you wish to obtain an ISBN.
Personally, I don't plan to use an ISBN for Kindle because Amazon has their proprietary Product ID number. I may keep my Nook books with the B&N Product ID number too.
I will not use ISBN for All Romance eBooks even though one of the formats I offer there for my books is an epub file. I prefer using the numbering system they assigned for me because it can cover all the formats I offer there.
I'll keep the Smashwords ISBN on the books I leave to be distributed from their own website and to any outlet that I can't reach with Bookbrewer.
To be successful, an author must not only write good books but also understand the business of book publishing and selling.
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