| 01 | Proprietary | Note that <IDTypeName> is required with proprietary identifiers | 10 | |
| 02 | Proprietary | Deprecated – use code 01 | 0 | 10 |
| 03 | DNB publisher identifier | Deutsche Nationalbibliothek publisher identifier | 1 | |
| 04 | Börsenverein Verkehrsnummer | (de: Verkehrsnummer ded Börsenverein des deutschen Buchhandels) | 1 | 63 |
| 05 | German ISBN Agency publisher identifier | (de: MVB-Kennnummer) | 1 | 63 |
| 06 | GLN | GS1 global location number (formerly EAN location number) | 1 | 9 |
| 07 | SAN | Book trade Standard Address Number – US, UK etc | 1 | 6 |
| 08 | MARC organization code | MARC code list for organizations – see http://www.loc.gov/marc/organizations/orgshome.html | 28 | |
| 10 | Centraal Boekhuis Relatie ID | Trading party identifier used in the Netherlands | 4 | |
| 12 | Distributeurscode Boekenbank | Flemish supplier code. Only for use in ONIX 3.0 or later | 59 | |
| 13 | Fondscode Boekenbank | Flemish publisher code | 7 | |
| 15 | Y-tunnus | Business Identity Code (Finland). See http://www.ytj.fi/ (in Finnish) | 8 | |
| 16 | ISNI | International Standard Name Identifier. A sixteen digit number. Usually presented with spaces or hyphens dividing the number into four groups of four digits, but in ONIX the spaces or hyphens should be omitted. See https://isni.org/ | 10 | |
| 17 | PND | Personennamendatei – person name authority file used by Deutsche Nationalbibliothek and in other German-speaking countries. See http://www.dnb.de/standardisierung/normdateien/pnd.htm (German) or http://www.dnb.de/eng/standardisierung/normdateien/pnd.htm (English). Deprecated in favor of the GND | 10 | 18 |
| 18 | NACO | A control number assigned to a Library of Congress Control Number (LCCN) Name Authority / NACO record | 10 | 51 |
| 19 | Japanese Publisher identifier | Publisher identifier administered by Japanese ISBN Agency | 12 | |
| 20 | GKD | Gemeinsame Körperschaftsdatei – Corporate Body Authority File in the German-speaking countries. See http://www.dnb.de/standardisierung/normdateien/gkd.htm (German) or http://www.dnb.de/eng/standardisierung/normdateien/gkd.htm (English). Deprecated in favor of the GND | 13 | 18 |
| 21 | ORCID | Open Researcher and Contributor ID. A sixteen digit number. Usually presented with hyphens dividing the number into four groups of four digits, but in ONIX the hyphens should be omitted. See http://www.orcid.org/ | 13 | |
| 22 | GAPP Publisher Identifier | Publisher identifier maintained by the Chinese ISBN Agency (GAPP) | 15 | |
| 23 | VAT Identity Number | Identifier for a business organization for VAT purposes, eg within the EU’s VIES system. See http://ec.europa.eu/taxation_customs/vies/faqvies.do for EU VAT ID formats, which vary from country to country. Generally these consist of a two-letter country code followed by the 8–12 digits of the national VAT ID. Some countries include one or two letters within their VAT ID. See http://en.wikipedia.org/wiki/VAT_identification_number for non-EU countries that maintain similar identifiers. Spaces, dashes etc should be omitted | 16 | |
| 24 | JP Distribution Identifier | 4-digit business organization identifier controlled by the Japanese Publication Wholesalers Association | 17 | |
| 25 | GND | Gemeinsame Normdatei – Joint Authority File in the German-speaking countries. See http://www.dnb.de/EN/gnd (English). Combines the PND, SWD and GKD into a single authority file, and should be used in preference | 18 | |
| 26 | DUNS | Dunn and Bradstreet Universal Numbering System, see http://www.dnb.co.uk/dandb-duns-number | 22 | |
| 27 | Ringgold ID | Ringgold organizational identifier, see http://www.ringgold.com/identify.html | 22 | |
| 28 | Identifiant Editeur Electre | French Electre publisher identifier | 24 | |
| 29 | EIDR Party DOI | DOI used in EIDR party registry, for example ‘10.5237/C9F6-F41F’ (Sam Raimi). See http://eidr.org | 29 | |
| 30 | Identifiant Marque Electre | French Electre imprint Identifier | 24 | |
| 31 | VIAF ID | Virtual Internet Authority File. <IDValue> should be a number. The URI form of the identifier can be created by prefixing the number with ‘https://viaf.org/viaf/’. See https://viaf.org | 29 | |
| 32 | FundRef DOI | DOI used in CrossRef’s Open Funder Registry list of academic research funding bodies, for example ‘10.13039/100004440’ (Wellcome Trust). See https://www.crossref.org/services/funder-registry/ | 27 | 65 |
| 33 | BNE CN | Control number assigned to a Name Authority record by the Biblioteca Nacional de España | 35 | |
| 34 | BNF Control Number | Numéro de la notice de personne BNF | 36 | |
| 35 | ARK | Archival Resource Key, as a URL (including the address of the ARK resolver provided by eg a national library) | 36 | |
| 36 | Nasjonalt autoritetsregister | Nasjonalt autoritetsregister for navn – Norwegian national authority file for personal and corporate names. Only for use in ONIX 3.0 or later | 37 | |
| 37 | GRID | Global Research Identifier Database ID (see https://www.grid.ac). Only for use in ONIX 3.0 or later. Deprecated – ROR is now generally preferred | 39 | 60 |
| 38 | IDRef | Party ID from Identifiers and Standards for Higher Education and Research (fr: Identifiants et Référentiels pour l’enseignement supérieur et la recherche). Only for use in ONIX 3.0 or later. See https://www.idref.fr | 52 | |
| 39 | IPI | Party ID from CISAC’s proprietary Interested Party Information scheme, used primarily in rights and royalies administration. Only for use in ONIX 3.0 or later | 57 | |
| 40 | ROR | Research organization registry identifier (see https://ror.org), leading 0 followed by 8 alphanumeric characters (including 2-digit checksum). Only for use in ONIX 3.0 or later | 58 | |
| 41 | EORI | Economic Operators Registration and Identification, identifier for businesses that import into or export from the EU. Only for use in ONIX 3.0 or later | 59 | |
| 42 | LEI | Legal Entity Identifier, administered by the Global LEI Foundation, as 20 alphanumeric characters without spaces or hyphens. Only for use in ONIX 3.0 or later | 62 | |
| 43 | SIREN | French business identifier, issued by the National Institute of Statistics and Economic Studies (INSEE). 9 digits, without spaces. Only for use in ONIX 3.0 or later | 63 | |
| 44 | SIRET | French business and location identifier, issued by the National Institute of Statistics and Economic Studies (INSEE). 14 digits (the SIREN plus a further five digits), without spaces, or occasionally an alphanumeric code. Only for use in ONIX 3.0 or later | 63 | |