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This document is an excerpt from the EUR-Lex website

Technical information

The 3 features outlined below can be implemented independently. To benefit fully from Linked Data, however, all 3 should be used.

  1. URI template/patterns

    ELI's HTTP URIs enable users to access legislation in a persistent way. The URIs are formally described by machine-readable templates, using semantic components from a legal and an end-user point of view.

  2. Metadata

    ELI metadata describes legal information in a standardised way. Publishers of legal information are free to use their own metadata schemas, but are encouraged to implement the ELI metadata schema as well.

  3. Ontology & metadata serialisation

    ELI metadata elements can be serialised in accordance with the W3C Recommendation, 'RDFa in XHTML: Syntax and Processing', following the ELI ontology.

    You can download the latest version of the ELI ontology from the EU Vocabularies page.

How to describe and disseminate your ELI datasets

As ELI progresses toward making legal metadata more reusable, it should lower the barrier for data consumers to retrieve the ELI metadata from an ELI provider. A way of achieving this is by legislation publishers describing and publishing ELI datasets. The following document explains how to best describe and disseminate ELI datasets with a view to making legal data more reusable: Specifications to describe ELI datasets.

EU Publications Office services


CELLAR stores and disseminates all content and metadata created or disseminated by the Publications Office. It also drives the Publications Office's major portals, including EUR-Lex and OP Portal.

CELLAR resources are semantically described by the CDM (Common Data Model), an FRBR-compliant OWL ontology, which also serves as the basis for the Publication Office's ELI implementation. It is publicly accessible and allows all interested parties to retrieve content and its RDF structured metadata for reuse. A public SPARQL endpoint is made available to query its metadata store.

EU Vocabularies

The Publications Office's EU Vocabularies website provides access to a number of value lists relevant to the implementation of ELI, including the Named Authority Lists (NAL):

  • resource types
  • places
  • corporate bodies
  • languages
  • subdivisions.


RDFEdit allows users to search, display and edit the metadata of legal resources in the Publications Office's Cellar database (an RDF triplestore database).

It includes the RDForms JavaScript template mechanism, enabling RDF data to be easily displayed or edited.

While RDFEdit contains some coding specific to the Cellar API (to load RDF data and generate update instructions, for instance), its architecture is entirely generic and relies on OWL ontology parameters and additional annotations to display and edit templates.

Last update: 21/03/2023