The EUPL (European Union Public Licence) is a copyleft open-source licence initiated by the European Commission, available in 23 official linguistic versions. It is OSI-certified and recognised by the Free Software Foundation as a free software licence.

Key Features of the EUPL

• Copyleft & Compatibility: Ensures that derivatives remain open while allowing interoperability with major reciprocal licences (e.g., GPL, AGPL, LGPL, CeCILL, EPL, MPL).
• Interoperability: Applied under European law, ensuring free reuse of interfaces, APIs, and data structures for linking with independent components.
• Multilingual: All 23 linguistic versions are legally equal.
• Broad Scope: Covers software and ancillary data, including SaaS distribution, like a more compatible AGPL.
• Developer Certificate of Origin (DCO): Included for contribution tracking.

Licensing Under EUPL

To license work under the EUPL, simply state “Licensed under the EUPL” in the source and documentation. To specify a version, use “Licensed under the EUPL-1.2-or-later”.