On Tuesday 18 October 2011,  the Court of Justice of the European Union (the "CJEU") issued its long awaited decision in the Brüstle v Greenpeace case concerning the patentability of inventions involving human embryonic stems cells (“hESCs”). 

The CJEU found that an invention is excluded from patentability under Article 6(2)(c) of the Biotechnology Directive where the implementation of the process requires either the prior destruction of human embryos or their prior use as base material, even if, in the patent application, the description of that process, as in the present case, does not refer to the use of human embryos. Furthermore, the CJEU concluded that scientific research entailing the use of human embryos cannot access the protection of patent law although the uses of human embryos for industrial or commercial purposes is not excluded under the Directive to the extent that the invention concerns the use for therapeutic or diagnostic purposes which are applied to the human embryo and which are useful to it, for example to correct a malformation and improve the chances of life. 

However, the CJEU said that in regard to patents involving hESCs which are obtained from a human embryo at the blastocyst stage of development, it was for the referring court to ascertain, in the light of scientific developments, whether they are capable of commencing the process of development of a human being which if so would be excluded from patentability.

Article 6(2)(c) of the Biotechnology Directive 98/44/EC states that inventions involving the "use of human embryos for industrial or commercial purposes", are unpatentable in EU Member States.

Greenpeace argued in proceedings launched initially in Germany that Professor Brüstle's European patent was unpatentable because it describes and claims the isolation and purification of "precursor cells" generated from hESCs.  Brüstle claimed that these cells could treat a variety of serious neurological conditions including Parkinsons. These hESCs derive from pluripotent stem cells in the very early stages after fertilisation of an egg. 

On appeal the Bundespatentgericht (Federal Patent Court) stayed the action and referred questions on the meaning of Article 6(2)(c) to the CJEU. The questions asked may be summarised as whether an invention involving hESCs, which are derived from an embryo destroyed when the precursor stem cells were acquired, are excluded from patentability because it is use of a human embryo for industrial or commercial purposes.  In other words, are hESCs obtained in this way an "embryo" within the patentability exclusion? The Bundespatentgericht also asked whether the exclusion from patentability of an invention involving the "uses of human embryos for industrial or commercial purposes" also excludes any commercial exploitation for the purposes of scientific research. 

In March 2011, the Advocate General Yves Bots ("AG") issued an initial opinion and concluded that if a technical process for which a patent is filed necessitates the prior destruction of an embryo, then even if the patent description does not contain any reference to the use of embryos or the source of the cells, the invention must be excluded from patentability.  The AG also found that the expression "embryo" in Article 6 of the Directive required a Community-wide interpretation (immediately after fertilisation of an egg) even though the Directive does not provide a definition.

While the AG did not come to a clear conclusion on the second point regarding the patentability of inventions which involve the commercial exploitation for scientific research purposes, he raised strong ethical objects to such use of embryonic material. 

The CJEU appears to have made a similar finding to the AG.  While this decision may be an unwelcome development in stem cell research centres around the UK, it is not necessarily catastrophic for the sector because:

  1. it will be possible to obtain such patents in other jurisdictions (including the US);
  2. other aspects of any therapy may be patentable in Europe; and
  3. it will still be difficult for third parties to supply generic (or biosimilar) version of a hESC therapy to market.

At this stage, it is uncertain what effect the CJEU's ruling will have on the grant of European patents by the European Patent Office to hESC inventions.  The CJEU decision needs to be seen in context of the decision of the Enlarged Board of Appeal in G 2/06 (the "WARF Decision") which also concerned the meaning of Article 6(2)(c) which arose during an opposition proceedings at the European Patent Office (EPO).  According to the EBA, Article 6(2)(c) (or rather its equivalent EPC provision Rule 28(c)) forbids the patenting of claims directed to products which, as described in the application at the filing date, could be prepared exclusively by a method which necessarily involved the destruction of an embryo from which the said product was derived, even where the method was not part of the claim.