ePO History and Planned Developments

eProcurement Ontology overview

Several initiatives around eProcurement in the EU had been launched prior to 2016, driven by the public sector, industry, and academia. Some had grown organically, while others were the result of standardisation work.

The vocabularies and the semantics that they introduced, the phases of public procurement that they covered, and the technologies they used, differed greatly. These differences hampered data interoperability and reuse.

The situation created a need for a common representation of the knowledge around eProcurement as it is practiced in the European Union. This meant that a common vocabulary, and both common axioms and rules were needed.

In 2016 the Publications Office of the European Union (Publications Office or OP) initiated a project to manage and support the development of an electronic Procurement Ontology (ePO), funded by the ISA2 Programme. The aim of the project was to develop an eProcurement Ontology based on the open-source OWL (Web Ontology Language) standard, and make it available to EU member states. Since 2021, the project has been funded by the Digital Europe Project (DEP).

This project was in conjunction with a parallel project to develop the associated eForms.

The ultimate objective of the ePO was (and still is) to conceptualise and formally encode eProcurement data, and to make it available in an open, structured, and machine-readable format. This data would cover the process from end-to-end, i.e., from notification, through tendering, awarding, ordering, invoicing, and finally to payment.

To achieve this, the EU Publications Office (OP) engaged a working group of experts (WG) with the mission of building consensus on the analysis, results, and deliverables developed by the OP teams. The working group continues to work with the OP on the ePO.


2017 - 2023

2017 2023

2024 - 2025

2024 2025

Date Published Version Notes


ePO version 1.0.0

Materials made public and accessible through the ISA2 Joinup platform, including Working Group discussions.

January 2018

ePO version 2.0.0

Improved and extended version 1.0.0. Version 2.0.1, released later that year.

August 2022

ePO version 3.0.0

eNotice module released in v3.0.1 and eOrdering module released in v3.1.0. Going forward, the ePO project funded by the Digital Europe Project (DEP).

July 2023 and December 2023

ePO version 4.0.0

eFulfilment and eContract modules released in v4.0.0

March 2024

ePO version 4.1.0-rc.1

eAccess & eSubmission modules released in v4.1.0-rc.1

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