GS1 Global Office

Avenue Louise 326 Brussels 1050 Belgium https://www.gs1.org/

This document describes a Uniform Resource Name (URN) namespace for Global Standards 1 (GS1). The namespace provides stable, unique, and persistent identifiers for GS1 identification keys, GS1 semantic artefacts, and GS1 standards and their components. The namespace includes three coordinated branches: an identification branch based on GS1 Application Identifiers (AIs), a semantic dictionary branch rooted at "urn:gs1:gdd:", and a standards branch rooted at "urn:gs1:std:". This document registers the formal URN namespace "gs1", defines its syntax, provides illustrative examples, and includes informative constraints to preserve important GS1 operational realities without overloading the core ABNF.

Introduction Global Standards 1 (GS1) is an international standards organisation that develops and maintains standards for identification, data capture, data sharing, and interoperability across supply chains, healthcare, retail, logistics, and digital ecosystems. GS1 standards include globally recognised identification keys such as the Global Trade Item Number (GTIN), Global Location Number (GLN), and Serial Shipping Container Code (SSCC). GS1 also maintains semantic artefacts and standards that define business information elements, business data types, code lists, and standard clauses used across multiple industries. This document registers the formal URN namespace "gs1" in order to provide stable, globally unique, and persistent identifiers across these domains.

• GS1 identification keys and related element strings.
• GS1 semantic dictionary artefacts.
• GS1 standards and their components.

The document is intentionally minimalist in scope. It focuses on URN namespace registration, syntax, examples, and validation. Resolver behaviour and OpenAPI details are retained as informative appendices.

Namespace Registration Template This registration follows the template in RFC 8141, Appendix A.

Namespace Identifiergs1

Registration InformationVersion: 1. Date: 2026-04-23.

RegistrantGS1 Global Office, Avenue Louise 326, 1050 Brussels, Belgium. URI: https://www.gs1.org/.

Relevant ancillary documentationRelevant ancillary documentation includes GS1 General Specifications, GS1 Application Identifiers, GS1 Digital Link Standard, GS1 GDD / GDSN semantic artefact construction rules, GS1 Resolver Standard, and EPC Tag Data Standard.

Community considerationsThe namespace is intended for use by GS1 Member Organisations, solution providers, retailers, healthcare organisations, logistics providers, regulators, standards publishers, and Semantic Web and knowledge graph communities.

Additional informationContact: GS1 Global Office. URI: https://www.gs1.org/. Change Controller: GS1 AISBL. Future revisions are controlled through GS1 governance processes and subsequent RFC publication where required.

Revision informationVersion 1. Initial registration.

Syntactic structure The GS1 URN namespace consists of three coordinated branches.

• Identification branch: urn:gs1:<ai>:<value>[:<ai>:<value>...]
• Semantic dictionary branch: urn:gs1:gdd:bie:<ref>; urn:gs1:gdd:bdt:<type>; urn:gs1:gdd:cl:<list>[:<value>]
• Standards branch: urn:gs1:std:<standard>[:<version>][:<clause>]

A full ABNF grammar, regular expressions, informative constraints, and illustrative examples are provided in the appendices.

Identifier uniqueness considerationsIdentifier uniqueness is guaranteed through GS1 governance. Identification-key values are governed by GS1 allocation rules, including GS1 Company Prefix governance where applicable. Semantic artefacts and standards references are assigned under GS1-managed governance processes.

Identifier persistence considerationsIdentifiers are never reassigned. Deprecation, withdrawal, replacement of standards, migration of semantic infrastructure, replacement of resolver technologies, or changes to publication formats SHALL NOT invalidate an assigned GS1 URN. The identifier remains valid indefinitely, even where the identified resource becomes obsolete or superseded.

Process of identifier assignmentNames are granted through GS1 processes. Depending on the branch, assignment is managed by GS1 Global Office, GS1 Member Organisations, or relevant GS1 semantic or standards governance processes.

Process of identifier resolutionResolution is optional. URN validity is independent of the existence of any resolver service. Resolver services provide a convenience mechanism for obtaining representations associated with a URN. GS1-authorised resolvers may provide authoritative representations. Example: https://resolver.gs1.org/resolve/[urn], where [urn] is the percent-encoded form of the URN.

Rules for lexical equivalenceThe literals "urn", "gs1", "gdd", "bie", "bdt", "cl" and "std" are case-insensitive. All assigned-value components are case-sensitive unless explicitly defined otherwise by GS1 governance. No Unicode normalisation, percent-decoding, case folding, or semantic interpretation is performed when determining lexical equivalence. Lexical equivalence is determined using RFC 8141 rules combined with the namespace-specific rules defined here.

Conformance with URN syntaxAll GS1 URNs conform to RFC 8141 and the specific ABNF grammar in Appendix A.

Validation mechanismSyntax validation may be performed using the ABNF and regular expressions in the appendices. Additional branch-specific semantic validation should be performed using the informative constraints and tables in this document.

ScopeThe namespace is global, covering GS1 identifiers, semantic artefacts, and standards references maintained or governed by GS1.

Namespace Considerations The "gs1" namespace is required to provide stable identifiers for GS1 artefacts across registries, implementations, APIs, and documentation. It enables persistent referencing, deduplication, caching, standards citation, semantic linkage, and long-lived references in publications and knowledge graphs. The namespace design deliberately separates identifiers, semantic artefacts, and standards references because these categories have different governance and syntactic needs. This reduces ambiguity and supports simpler validation and resolution. The "urn:gs1:gdd:" branch is preserved as a legacy-compatible semantic namespace. It identifies GS1-governed semantic artefacts independently of any particular implementation platform and remains valid even if the underlying semantic infrastructure evolves.

Relationship to RFC 5134 The GS1 URN namespace defined in this document does not replace, deprecate, or supersede the EPC URN namespace defined by RFC 5134. The two namespaces serve complementary purposes within the GS1 standards ecosystem. The EPC namespace is specifically designed to support Electronic Product Code (EPC) identification schemes and related EPC architectures. The GS1 namespace defined in this document provides a broader identifier framework covering GS1 identification keys and Application Identifiers, GS1 semantic artefacts, GS1 standards and standards components, and future GS1-governed identifier classes. The GS1 namespace therefore addresses categories of resources that are outside the scope of the EPC namespace while preserving compatibility with existing EPC deployments. Implementations MAY support mappings between EPC URNs and GS1 URNs where such mappings are defined by GS1 standards or implementation guidance. urn:gs1:01:09506000134352:21:9999]]> The existence of such mappings does not imply equivalence between the namespaces. Each namespace retains its own syntax, governance model, and resolution semantics. The GS1 namespace is intended to complement the EPC namespace by providing a consistent URN framework for the wider set of GS1-managed identifiers, semantic resources, and standards references. Additional illustrative mappings and mapping guidance are provided in Appendix G (EPC and GS1 Mapping).

Security Considerations GS1 URNs are opaque identifiers. Security considerations are therefore limited to those common to URNs in general and to the resolver infrastructure used around them. Use of non-authoritative resolvers may yield incorrect or outdated results. Resolver services should therefore use HTTPS to provide confidentiality and integrity, and clients should prefer GS1-authorised resolver services where semantic correctness matters. This registration does not itself create new security risks in identifiers. However, applications that dereference GS1 URNs should consider normal security issues for HTTP services, including spoofing, stale data, replay, and representation tampering. Intellectual property rights associated with identified artefacts are outside the scope of this registration.

IANA Considerations IANA is requested to register the Namespace Identifier "gs1" in the Formal URN Namespace Registry in accordance with RFC 8141. The registration template contained in Section 2 constitutes the formal registration request.

Normative References Informative References

Authors' Addresses GS1 Global Office, Avenue Louise 326, 1050 Brussels, Belgium. URI: https://www.gs1.org/.

Acknowledgement Funding for the RFC Editor function is currently provided by the Internet Society.

ABNF Grammar

Informative Constraints The ABNF intentionally defines a generic syntactic envelope. It does not encode all GS1 Application-Identifier-specific business rules because doing so would make the grammar unwieldy and difficult to maintain. Implementations should therefore apply additional semantic validation after successful syntactic parsing.

• AI 01 (GTIN): numeric only; exactly 14 digits.
• AI 00 (SSCC): numeric only; exactly 18 digits.
• AI 414 (GLN): numeric only; exactly 13 digits.
• AI 402 (GSIN): numeric only; exactly 17 digits.
• AI 17 (expiration date): numeric only; exactly 6 digits in YYMMDD form.
• AI 10 and AI 21: variable-length values validated according to GS1 rules.
• AI 253, 401, 8003, and 8004: validated according to their respective GS1 definitions.

Regular Expressions

Examples

• urn:gs1:01:09506000134352
• urn:gs1:00:195060001343521234
• urn:gs1:414:9506001343521
• urn:gs1:402:12345678901234567
• urn:gs1:8004:ABC123XYZ
• urn:gs1:01:09506000134352:10:ABC123:21:9999
• urn:gs1:01:09506000134352:17:250101
• urn:gs1:gdd:bie:TradeItem
• urn:gs1:gdd:bie:TradeItem.netContent
• urn:gs1:gdd:bdt:MeasurementType
• urn:gs1:gdd:cl:CountryCode:BE
• urn:gs1:std:genspec:24.0:5.3.1
• urn:gs1:std:epcis:2.0:4.2

Resolver Behaviour Resolver behaviour is informative and not required for URN validity. GS1-authorised resolvers should support representation negotiation while keeping URNs themselves stable and version-independent where appropriate.

• text/html
• application/pdf
• application/xml
• text/markdown
• application/ld+json

OpenAPI Resolver Annex

GS1 AI Constraint Tables Illustrative GS1 AI Constraints

AI	Meaning	Character set	Length or form
00	SSCC	numeric	exactly 18 digits
01	GTIN	numeric	exactly 14 digits
10	batch or lot	GS1-defined alphanumeric	variable
17	expiration date	numeric	YYMMDD
21	serial number	GS1-defined alphanumeric	variable
253	GDTI	GS1-defined	per GS1 definition
401	GINC	GS1-defined	per GS1 definition
402	GSIN	numeric	exactly 17 digits
414	GLN	numeric	exactly 13 digits
8003	GRAI	GS1-defined	per GS1 definition
8004	GIAI	GS1-defined alphanumeric	per GS1 definition

EPC and GS1 Mapping This appendix is informative and is provided to illustrate interoperability between the namespaces described in Section 3.1. The mappings shown herein do not establish semantic equivalence between the EPC and GS1 namespaces and do not alter the independent governance or syntax rules applicable to either namespace. The following is a non-normative example of mapping between an EPC identifier and a GS1 URN. urn:gs1:01:09506000134352:21:9999]]>