Publications Office of the EU
Ontologies - EU Vocabularies


An ontology – in the context of computer and information sciences – can be defined as a formal specification designed to delimit and group instances/concepts (facts, events, entities, elements, etc.) based on their common class (types, properties, interrelationships, etc.), and thus formalising a full or a subset of a domain.

EU Vocabularies - Template display
Common Data Model

The Common Data Model (CDM) is the formal description of the EU institution's official documents, legislative decision-making process, and its related publications.

More specifically, the CDM describes documents in the legal domain (e.g., the Official Journal, case law, consolidated legislation, preparatory acts, etc.), general publications (e.g., reports, periodical serials, books, brochures, etc.), the different entities related to their creation (e.g., the agent who wrote the document, the procedure and event of which it is the result, etc.), and their relations.

The model is based on the FRBR methodology which is well suited to describe multilingual and multiformat publications.

The CDM is an ontology described in Web Ontology Language (OWL) and it governs the respective document metadata instances in the Common Repository (Cellar). Its documentation can be obtained by dereferencing the ontology URI

This model is continually refined in collaboration with the business units to guarantee its quality with regards to the institutions’ needs for the structure of their metadata.

ECCF Core Ontology
The European Commission Conceptual Framework (ECCF) is a knowledge model for high-level enterprise descriptions of EU institutions and any other public service organization. It is intended as a core ontology to be extended with classes and properties specific for each policy domain and service. ECCF provides a formal representation of the following story describing Public Service organisations (PSO): A PSO provides Services via Actors, having Motivation and Capabilities, using Policy Instruments and Assets.
ELI Draft Legislation Ontology

The ELI Draft Legislation Ontology (ELI-DL) is an independent extension of the core ELI ontology. It enables the semantic annotation of bills, or legislative projects pages published in the portals of Official Journals or Parliaments.

ELI Impact Ontology

ELI Impact Ontology (ELI-I) is an extension to the ELI ontology that provides more comprehensive information about the impact analysis process, the impacts of modifying text and the updates to the consolidated version of the legislation in response to these changes.

ELI Ontology

The ELI (European Legislation Identifier) 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.

ERA vocabulary

ERA vocabulary is an ontology defined by the European Union Agency for Railways (ERA) to describe the concepts and relationships related to the European railway infrastructure and the vehicles authorized to operate over it. The infrastructure portion contains the Implementation layer that represents the railway network as a number of operational points (OPs) connected with sections of line (SoLs), describing the following structural subsystems of the Union rail system: the infrastructure subsystem, the energy subsystem, the trackside control-command and signalling subsystem. It also contains the Topological layer where the network topological concepts are defined. The Railway Vehicle types portion contains the route compatibility check-related technical characteristics of vehicle types.

The author of ERA vocabulary is ERA and it is published by the Publications Office of the European Union on the EU Vocabularies website.

EU Budget Vocabulary

The EU Budget Vocabulary and its RDF serialisation are designed to facilitate the exchange, increase the understandability and foster the reusability of budgetary information published by the EU. The Vocabulary aims to increase government transparency by improving the availability, usability and understandability of the EU Budget.

EUropean Research Information Ontology

EURIO (EUropean Research Information Ontology) conceptualises, formally encodes and makes available in an open, structured and machine-readable format data about resarch projects funded by the EU's framework programmes for research and innovation.

European Learning Model

The European Learning Model can be used to capture the results of any non-formal and formal learning across Europe, as well as the validation of non-formal and informal learning. It is designed to provide a single format to describe certificates of attendance, examination results, degrees and diplomas, diploma supplements, professional certifications, employer recommendations and any other kind of claims that are related to learning.

eProcurement Ontology
The objective of the eProcurement Ontology (ePO) is to put forth a commonly agreed OWL ontology that will conceptualise, formally encode and make available in an open, structured and machine-readable format data about public procurement, covering it from end to end, i.e. from notification, through tendering to awarding, ordering, invoicing and payment. It aims at unifying existing practices, thus facilitating seamless exchange, access and reuse of data. eProcurement Ontology is maintained by the Publications Office of the European Union on the EU Vocabularies website.