AGID (the Government Agency for Digital Italy) had updated, dated May 9. 2019, its guidelines on the procurement and reuse of software by public administrations (“Linee guida su acquisizione e riuso di software per le pubbliche amministrazioni").
The guide highlights the interest of open source procurement, while noting that integrating several components covered by various licences requests a serious compatibility analysis: how far can the resulting integration be re-distributed and under which licence(s)?
Section 3.5.3 of the guidelines, dedicated to the choice of a licence, notes that licence proliferation (the multiplication of different licences that are sometimes incompatible) makes the reuse and redistribution of software more difficult, hazardous and costly.
When a software has been obtained from a third party under a specific open source licence and must be further shared or re-distributed, the general recommendation is to respect the primary licence and to reuse the same licence: relicensing under different terms should be avoided.
When the software or combination is new in all or part (original software produced by public administration in Italy) the general rule is to adopt the European Union Public Licence (EUPL - code SPDX: EUPL-1.2) because this licence, which is open source, copyleft and protecting the work from exclusive appropriation, grants a maximal interoperability at European level, has an original working value in Italian and is compatible with the most used other licences, reducing strongly the risk of incompatibility.
More information (the guidelines, in Italian):