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The Global Language of Business

Release 1.0.0, October 2026

Change management process for the GS1 Web Vocabulary, including link types

How to submit a work request for a new term in the GS1 Web Vocabulary, including link types, and how the request will be processed.

This document defines the processes through which new terms are added to the GS1 Web Vocabulary. It distinguishes between the process followed for defining new classes, properties and code lists on the one hand, and link types on the other.

This document was written and is maintained by the GS1 Web Technology Standards Maintenance Group. It defines the process that is followed when handling Work Requests affecting the GS1 Web Vocabulary. It may be updated or made obsolete at any time.

TBC

The term "link type" was introduced to the GS1 lexicon in version 1.1 of the GS1 Digital Link standard in February 2020. It is an abbreviation of the term "link relation type" that goes back to the original definition of the World Wide Web in the early 1990s and a concept that goes back much further.

Increasing demand for new link types that has prompted the development of this process document that sets out a series of questions that:

  1. The greater the number of link types, the less each one is used, the less consistent each use is likely to be, and the more likely it is to find overlap or duplication. Therefore a minimum number of link types produces the maximum interoperability.
  2. The definition of a link type should be succinct, clear and unambiguous.

    It is easier to assess whether a given use case matches a succinct definition than one that takes a whole paragraph to explain. That said, a definition that is too short may sacrifice the clarity that implementers need to correctly understand what the link type is intended to be used for.

  3. Closely related to the previous point, link types are a high level categorization.

    For example, the definition of gs1:dpp is simply A link to a digital product passport. It does not imply that the linked DPP meets legislation in a particular jurisdiction. Likewise gs1:appDownload's definition is A link to a related mobile app, it does not distinguish between apps for different platforms.

  4. Link types should not include information that can be declared by other means.

    When used to describe a link (URL) that points to a particular resource, the link type is not the only piece of metadata. Language, format (media type) and title should all be used to provide additional descriptions of linked resources. These attributes are long-established within the relevant HTTP and HTML standards.

    This means that link types must not specify a particular format or language. For example, the single gs1:pip link type could point to one or more product description pages available in any permutation of HTML, French, Markdown, Chinese, Thai, JSON-LD, Swedish and PDF. They're still product information pages.

    A Web client (e.g. browser) can use:

    • HTTP Accept header to request the resource in a specific media type, e.g. application/ld+json for JSON-LD, text/html for HTML;
    • HTTP Accept-Language header to request the resource in a specific human language, e.g. fr, de for French or German respectively.

    A responding resource may use:

    • HTTP Content-Type header to specify the media type of the returned representation of the resource, e.g. application/ld+json, text/html;
    • HTTP Content-Language header to specify the human language in which a resource is provided, e.g. fr, de respectively.

    Further information about content negotiation can be found in RFC 7231.

Link types may be defined by any working group chartered under GSMP, however, at the time of writing, the Web Technology SMG has primary responsibility for the GS1 Web Vocabulary and therefore the definition or deprecation of link types.

A proposal for a new link type should be submitted as a GSMP Work Request. The proposal must comprise all of the four components below:

  1. The "name" proposed for the link type itself.
  2. A proposed, succinct and clear definition.
  3. Illustrative examples of the kind of Web resource to which a link of this type would be expected to target.
  4. A brief explanation of the business value and an example where this link type will be used.

For example:

Name:
dpp
Definition:
A link to a digital product passport
Typical Web-resource:
Regulations in multiple jurisdictions may require that manufacturers provide a Digital Product Passport (DPP). A typical usage example might be a consumer scanning the QR Code on a shoebox to find where the leather came from. The precise definition and data content of a DPP will vary between jurisdictions but they tend to cover provenance, sustainability, recycling and repair information.
Business Purpose or Value:
For many categories of product, provision of a DPP is a legal requirement.

Once these four elements have been created, the following flow chart can be used by proposers and reviewers operating under GSMP to decide whether the new link type should be adopted.

Given the four elements as input, is there an existing link type that could be used? If so, stop. If not, could an existing link type definition be broadened slightly to meet your needs? If so, broaden the existing definition. If not, Is the proposed definition succinct, unambiguous and applicable beyond your immediate use case? Refine until the answer is yes. Submit the proposal.
The link type decision tree
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