| 00 | Unspecified | | 0 | |
| 01 | Publisher | | 0 | |
| 02 | Publisher’s distributor | Use to designate a distributor providing primary warehousing and fulfillment for a publisher or for a publisher’s sales agent, as distinct from a wholesaler | 0 | 46 |
| 03 | Wholesaler | | 0 | |
| 04 | Bibliographic agency | Bibliographic data aggregator | 0 | |
| 05 | Library bookseller | Library supplier. Bookseller selling to libraries (including academic libraries) | 0 | |
| 06 | Publisher’s sales agent | Use for a publisher’s sales agent responsible for marketing the publisher’s products within a territory, as opposed to a publisher’s distributor who fulfills orders but does not market | 4 | |
| 07 | Publisher’s conversion service provider | Downstream provider of e-publication format conversion services (who might also be a distributor or retailer of the converted e-publication), supplying metadata on behalf of the publisher. The assigned ISBN is taken from the publisher’s ISBN prefix | 15 | |
| 08 | Conversion service provider | Downstream provider of e-publication format conversion services (who might also be a distributor or retailer of the converted e-publication), supplying metadata on behalf of the publisher. The assigned ISBN is taken from the service provider’s prefix (whether or not the service provider dedicates that prefix to a particular publisher) | 15 | |
| 09 | ISBN Registration Agency | | 18 | |
| 10 | ISTC Registration Agency | | 18 | |
| 11 | Retail bookseller | Bookseller selling primarily to consumers | 28 | |
| 12 | Education bookseller | Bookseller selling primarily to educational institutions | 28 | |
| 13 | Library | Library service providing enhanced metadata to publishers or other parties | 36 | |