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LEOS is a web tool to support the legislative drafting in the EU with online collaboration, version control, and co-editing. It utilises Akoma Ntoso XML schema. It is an EC solution.
Owner
European Commission
Contact information

LEOS (Legislation Editing Open Software) is an open source software designed to help those involved in draſting legislation, which in itself is a complex knowledge-intensive process, by supporting efficient online collaboration. Comments, suggestions, version control, co-edition, everything is there. Regarding the structure, that is where we aim to be as restrictive as possible and this is not because we are conservative, but because this helps the draſters follow the rules and avoid mistakes. Content is stored in an XML format, currently Akoma Ntoso V3.

LEOS (Legislation Editing Open Software) is a project under Interoperable Europe initiative of the European Commission for a reinforced public sector interoperability policy, funded by the Digital Europe Programme (DIGITAL).

The LEOS project under Interoperable Europe focuses on supporting the co-development co-design, and co-deployment of an ‘IT eco-system centred on augmented LEOS’

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LEOS has been created to addresses the modernisation and digital transformation of the drafting and revising of legislation in Member States, EU Institutions, EU agencies and bodies. The aim is to:

  • Improve the quality of legislation.
  • Increase the efficiency of the legislative process across the Union.
  • Facilitate interoperability and seamless cooperation between the different actors in the legislative process in and between EU Institutions and Member States.
  • Improve transparency and accessibility and thus effectiveness of law.
  • Explore and pilot the use of innovative technologies such as Artificial Intelligence.

It is based on the Akoma Ntoso XML format an OASIS LegalDocML standard (in particular, it supports the AKN4EU interinstitutional instantiation subschema of Akoma Ntoso) that facilitates interoperability between Member States and EU institutions.

The code of augmented LEOS is available for free under EUPL licence (version 1.2 or – as soon they will be approved by the European Commission - subsequent versions of the EUPL (the "Licence")), and the development team paid attention to organise the code in a structured way to ease its reusability (modules, plugins…).

The current modules of augmented LEOS can be found on code.europa.eu (open source project repo from EU institutions):

For more information on the EUPL licence, please visit this link

Important to note that our journey started under ISA Programme with ISA Action 1.13. LEOS - Legislation Editing Open Software, when we first developed a better understanding of the way public administrations address the issue of drafting their legislations, with a view to identify best practices, improvements and areas where common efforts and developments are possible. We also invested time on researching the best open standards and tools so that we could be cost efficient and deliver open source for our community. And we keep doing this every time we need to add new features. Having identified an opportunity in the field, the project delivered various proof of concepts and prototypes. Now we have an execution phase every year where we constantly improve our tool. After ISA Action 1.13, LEOS continued under ISA² Action 2016.38 Legislation Interoperability Tools – LegIT until the end of ISA² Programme.

Last update: 15/09/2023

Our LEOS experience

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LEOS reuse story - European Commission

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v5.0.3.
Release date: 26/04/2024

LEOS

Virtual event

Joinup User Group Meeting (19/04/2024)

Collaboration
v5.0.2.
Release date: 07/03/2024

LEOS

v5.0.1.
Release date: 09/01/2024

LEOS

v5.0.0.
Release date: 12/12/2023

LEOS

v4.0.2
Release date: 04/07/2023

LEOS

v4.0.1
Release date: 20/06/2023

LEOS

Detailed information

Last update
Solution type
Interoperable Digital Solution
Languages
English
Status
Under development
Geographical coverage
European Union
Release version
5.0.3.
Release date

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