European Legislation Identifier (ELI)
The European Legislation Identifier (ELI) is a framework to make legislation metadata available online in a standardised format, so that it can be accessed, exchanged and reused across borders. For general information about ELI (governance, tools and news), and the implementation status of ELI by various stakeholders (in particular, the way ELI is implemented by the Office of Publications on Eur- Lex), please consult the ELI Register on Eur-Lex.
ELI technical specifications
The European Legislation Identifier framework includes technical specifications on:
- Web identifiers for legal resources (building on URI templates at European, national and regional levels, based on a defined set of components)
- Metadata set specifying how to describe legal information, and its expression in a formal ontology
- Recommendations for exchanging legislation in machine-readable formats, integrating metadata into legislative website
Pillar 1: Web identifiers (URI Templates)
ELI has proposed a set of URI template components that ELI publishers can arrange in any order to specify their own URI pattern. They are documented in this overview of reference URI template components.
If you are looking for the specific use of the ELI components on EUR-Lex, please read the implementation page of ELI by the Publications Office.
The ELI URIs defined by each of the ELI publishers serve as global web identifiers of legislation.
Pillar 2: ELI metadata and ontology
The ELI ontology defines a common data model for exchanging legislation metadata on the web; the primary users of the ELI model are the official legal publishers of EU Member States, and the model can also be used by other organisations. The description of legislation in ELI follows the principles of FRBR.
The current version of the ELI ontology is disseminated in the following files:
- The OWL reference file of the ELI ontology
- The table of the metadata elements of the ELI ontology, in HTML or XLSX
- The diagrams of the ELI ontology model
- The alignment of the ELI ontology with the schema.org legal extension, in OWL and in XLSX
- The release note of the latest version of the model
For accessing all the different versions of the ontology, see the ELI version history on EU Vocabularies.
Pillar 3: Integration of ELI metadata into legislative websites
ELI metadata must be encoded either:
- In RDFa, following the W3C Recommendation of 14 October 2008 "RDFa in XHTML: Syntax and Processing"
- In JSON-LD, following the W3C Recommendation of 16 January 2014 "JSON-LD 1.0 - A JSON- basedSerialization for Linked Data"
Implementers are free to support additional serialization formats.
ELI/XML is an encoding of ELI metadata in an XML schema (XSD). It can be used standalone or imported into other XML documents, typically in a metadata header.
The ELI/XML schema – facilitating the integration of ELI in XML-based document workflows – is provided with a set of XML transformations to generate ELI in RDF/XML, RDFa header or HTML+RDFa. ELI/XML is not supported as a dissemination format of ELI metadata.