The EU Public License is a copyleft license that probably qualifies as free software but is incompatible with the GNU General Public License.
Official EU documents
![[WWW]](/wiki-htdocs/modern/img/moin-www.png){kind=small}
http://europa.eu.int/idabc/en/document/2623/5585#euplComments from FSFE
Comments from debian-legal
A dicussion on the debian-legal mailing list has produced these comments. I haven't looked at them but they might have some useful information.