The Court of Justice of the European Union has ruled on patentability of scientific stem cell research

Scientific research which involves removal of a stem cell from a human embryo at the blastocyst stage, entailing the destruction of that embryo, cannot be patented.  However, the use of human embryos for therapeutic or diagnostic purposes which are applied to that human embryo is patentable (but their use for purposes of scientific research is not patentable).

The Court also defined human embryo:  “any human ovum must, as soon as fertilized, be regarded as a human embryo if that fertilization is such as to commence the process of development of a human being.”