The Court of Justice of the European Union (CJEU) has concluded that the use of an organism that is not capable of developing into a human being as a source of stem cells does not contravene a legal ban on patenting.

The use of human embryos as a source of stem cells is not patentable in Europe, and the CJEU has previously held that any human egg cell that has been stimulated to start the developmental process to become a human being falls within the legal prohibition on the use of human embryos, regardless of whether that human egg cell has been stimulated naturally by fertilisation with a human sperm cell, or artificially by transfer of a cell nucleus or by a process of asexual reproduction that does not involve fertilization (called parthenogenesis).

However, despite being capable of starting the developmental process, parthenogenesis does not allow human egg cells to continue on to develop into a human being. Knowing this, the High Court of Justice (England and Wales) asked the CJEU whether a human egg cell that has been stimulated to start the developmental process must also be capable of becoming a human being in order to fall within the definition of the legal concept of ‘human embryo’. The CJEU has answered the question by concluding that, in order to be classified as a ‘human embryo’, a human egg cell must have the inherent capacity of developing into a human being. Consequently, the mere fact that a human egg cell stimulated artificially by parthenogenesis starts the developmental process is not sufficient for it to be encompassed by the legal prohibition.

Essentially, the CJEU has decided that the definition of human embryo in the context of the legal ban on patenting rests on whether there is an inherent capacity of developing into a human being; which offers an opportunity for applicants to secure patents relating to stem cells by using a human egg cell stimulated artificially by parthenogenesis as a source of the stem cells. Previous decisions in the field of patenting stem cells have attracted opposition from activists at variance with the source of the stem cells. However, given that parthenogenesis does not allow human egg cells to continue on to develop into human beings, the present decision might represent a resolution for both patent applicants and lobbyists alike.