Open your codes and software

Licenses and intellectual property

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Intellectual property applicable to codes and software

Software is protected by copyright if it is possible to prove its originality. The Agence pour la Protection des Programmes (APP) has published a white paper to help software designers define the originality of their work. Copyright applies from the moment the software is created, so it is essential to be able to date this creation. This proof can be provided by any means, although there are some dedicated mechanisms, in particular registration with the Agence pour la protection des programmes. For software created by a public agent in the exercise of his or her duties, the economic rights are the property of the employing administration, in accordance with article L.113-9 of the French Intellectual Property Code (CPI): “In the absence of statutory provisions or stipulations to the contrary, the economic rights to software and its documentation created by one or more employees in the performance of their duties or on the instructions of their employer are assigned to the employer, who alone is entitled to exercise them”. Note: algorithms, which are considered to be mathematical formulae, and features, which are considered to be ideas or concepts, cannot be protected.

Software licenses

A software licence is a contract under which the owner of the copyright in a computer programme defines with its co-contractor (the operator or user) the conditions under which the programme may be used, distributed or modified.

To have the right to use software, the copyright holder must authorise it. The license is the document in which the owner lists the rights he grants to the licensee (to install the software, to use it, to make a backup copy). Using unlicensed software of which you are not the author is equivalent to infringing copyright. (source Wikipedia).

If there is no explicit right under a license, using software is an infringement of copyright. Article L. 335-2 of the CPI states that “any person using, copying, modifying or distributing the software without the explicit authorisation of the holders of the proprietary rights is guilty of counterfeiting and punishable by three years of imprisonment and a €300,000 fine“. To enable other users to use the code or software produced as part of their research, it is essential to allocate a usage license. There are two main types of license:

  • Free or Open Source licenses
  • Proprietary licenses, meaning that at least one of these actions is prohibited or restricted by the owner: use, study, modify, redistribute.

It is possible to give to a software several licenses. It is therefore possible to have software under both free and commercial licenses. This site explains the benefits of this approach.

Focus on free licences

There are different types of free licences:

  • permissive or non-copyleft: the initial license does not apply. Permission to redistribute and modify, but also to add restrictions
  • weak copyleft: the initial license remains but add-ons may have a different licence.
  • strong copyleft: the initial license applies to everything. A contaminating license.
TypeExamples of licences
permissive or non-copyleftBSD license; Apache License 2 MIT; CeCILL-B
weak copyleftGNU library or « Lesser » General Public License (LGPL); CeCILL-C
strong copyleftGNU General Public License EUPL; CeCILL

In order to avoid a proliferation of licenses, the Law for a Digital Republic introduced a list, to be set by decree, of licences that can be used by public authorities to re-use their public information free of charge, whether it be data or software source code. (article D.323-2-1 of the Code of relations between the public and the administration (CRPA)): consult this list.

Example of the GPL license

This is the best-known and most widespread licence in the free software world. It authorises, without the author’s consent and without fear of infringement action :

  • using the software
  • studying how the software works
  • adapting the software to user needs
  • copying and sharing with friends or colleagues
  • improvement of the software by the user and distribution of the modified software to the public.

This is a so-called contaminating license! It requires the user to redistribute these modifications under the GPL license. This means that all software that re-uses a piece of GPL code is contaminated by the GPL.

Example of Berkeley System Distribution license

This is a very non-restrictive licence: software distributed under the BSD licence may be freely copied or modified.

Note that the numerique.gouv.fr website recommends two default licences:

  • Permissive: Apache 2.0
  • With obligation of reciprocity: GNU GPL v3 (standard, lesser or affero)

To give two examples of physics software, the Smilei project (a simulation tool for hot plasma physics) uses a CeCILL-B licence. The Webobs project (a multi-disciplinary real-time observation tool used to observe natural phenomena, volcanological and seismological observatories) uses a GNU licence.

A tool to help you choose a licence

There are two websites where you can use questions and answers to find out which licences are best suited to your code:

Guides and resources

There are also several guides to help you:

  • The Etalab website offers a legal guide to help define the constraints associated with the publication of government (and therefore also research) source code
  • The data.gouv website lists approved reuse licenses, in particular those applicable to codes
  • P. Moreau, C. Moulin, J. Pappalardo, F. Pellegrini (2017). Fondamentaux juridiques. Collaboration et innovation ouverte, 2nd edition, Les livrets bleus du logiciel libre.
  • Lila Ammour, Anne-Sophie Bonne, Patrick Moreau, Jean-Marc Schmittbiel, Jean-Christophe Souplet. Je code : quels sont mes droits ? Quelles sont mes obligations ?. 2019. hal-02399517.