Following appeals by the opponents, the Technical Board of Appeal, as the judicial instance of the European Patent Office (EPO), had found the claims for chimpanzees and other animals to be unpatentable. It referred to a rule according to which patents on the genetic modification of animals are prohibited if this may result in "suffering from of animals without substantial medical benefit to man or animal".
Source:
https://www.welt.de/regionales/bayern/article210835997/Jahrelanger-Rechtsstreit-Patente-auf-Schimpansen-ungueltig.html