ISBN registration group
ISBN group 978-99951 — Reserved Agency
ISBNs beginning 978-99951 are issued for Reserved Agency. The group identifier has 5 digits.
Registrant (publisher) ranges
| Registrant range | Registrant digits | Publication digits | Titles per registrant | Registrants in range |
|---|---|---|---|---|
| 0000000–9999999 | — | — | — | Not yet assigned |
Shorter registrant numbers are issued to larger publishers (more publication digits = more titles).
Reading an ISBN from this group
Every ISBN in this group starts 978-99951-. The next digits are the registrant; look up which range the following seven digits fall into to know how long the registrant element is. For example, if the registrant has 2 digits, the publication element has 2 digits, then comes the check digit.
Check, convert or hyphenate any ISBN with the ISBN converter, and make a print-ready barcode with the ISBN barcode generator.
Sources & data
- International ISBN Agency RangeMessage (Fri, 6 Nov 2026 03:30:05 UTC).