Clear licensing rules are the regulatory basis for the sharing and reuse of software solutions, supporting legal interoperability. The European Commission has published the European Union Public License (EUPL), which is "the first open source licence with a working value in all EU official languages". The EUPL is "share-alike/reciprocal", like the LGPL but adding coverage of remote distribution. However, other licences may as well facilitate the compatibility or the interoperability of the solutions making use of them. This collection is meant to provide a guide for all IT developers, practitioners and users to define the conditions under which a certain solution may be freely shared and reused, taking into account the peculiar difficulties of identifying the applicable legal framework to such purposes.

By Decision C (2021) 8759, the EUPL is provided for European Commission distributed software.