In 1996, the Wisconsin Alumni Research Foundation (WARF) filed an EU patent application (with a priority date of 1995 being the priority date of its corresponding US patent applications). The application was for a method of obtaining certain embryonic stem cells (ESCs) from primates (including humans) and culturing stem cell lines derived from those ESCs. At the time of filing, the method necessarily involved the destruction of the primate or human embryo in order to extract the ESCs and culture them to form a stem cell line. This application included claims covering the resulting ESCs and stem cell lines. The European Patent Office (EPO) rejected this patent application as being contrary to "ordre public" or morality under Article 53(a) of the European Patent Convention 2000 (EPC) (see our previous e-bulletin on this decision:

WARF appealed this decision to the EPO's Technical Board of Appeal, which in 2006 referred four questions to the Enlarged Board of Appeal of the EPO for clarification.
On 25 November 2008, the Enlarged Board of Appeal of the EPO delivered its decision (G/206), in relation to these four questions, by holding that under the EPC it is not possible to grant a patent for an invention which necessarily involves the use and destruction of human embryos. This ruling rejected WARF's appeal and upheld the decision of the EPO by confirming that WARF's product invention was considered to be contrary to "ordre public" or morality under Article 53(a) EPC. Significantly, it was also held to be irrelevant that since the date of filing of WARF's patent application, ESCs (including those claimed in WARF's patent application) can now be obtained using methods without necessarily destroying human embryos as part of the process. The important date for consideration was the state of the available technology as at the date of filing of the patent application not as at the date of examination and any decisions made by the EPO.

As part of its decision, the Enlarged Board of Appeal of the EPO stressed that it was not making any rulings or statements as to the patentability of human ESCs. As yet, the UK Intellectual Property Office has not changed its approach in relation to the patentability of human ESCs, being that provided the resulting ESCs are not totipotent (being capable of producing all types of cells needed to create a human being), it considers inventions in relation to human ESCs to be patentable (provided the usual requirements of patentability are also met).

Therefore, unfortunately for those involved in human ESC research and development, the state of patent law on a worldwide scale has still yet to reach a consensus. In the US, WARF's inventions covering both methodologies, the resulting human ESCs and human stem cell lines have been held patentable. In the EU, WARF will not enjoy the same level of protection and neither will its competitors if the relevant invention necessarily involves the destruction of a human embryo. However, what is not certain going forward is whether an invention in relation to human ESCs that does not necessarily involve the destruction of a human embryo will be considered by the EPO to be patentable.

Whilst some entities involved in research in this field will be happy with this decision as it relieves them of the task of navigating the WARF patent minefield, others will be forced to reconsider their research programmes in the knowledge that resulting inventions may not be considered to be intellectual property capable of protection by a patent and therefore, potentially not as valuable an asset.