In 2002, the much-discussed "Edinburgh" patent (EP 0695351) was maintained in an amended form during opposition proceedings before the European Patent Office (EPO). The patent, filed in the name of the University of Edinburgh, has the title "Isolation, selection and propagation of animal transgenic stem cells". The grant of the patent had led to fierce protests and triggered a major public debate on the patenting of stem-cell technology.
The patent describes a method of using genetic engineering to isolate stem cells, including embryonic stem cells, from more differentiated cells in a cell culture in order to obtain pure stem cell cultures. The public debate centred on whether the patent extended to humans.
The result of the opposition proceedings was that the patent was amended so that it no longer included human or animal embryonic stem cells, but still covered modified human and animal stem cells other than embryonic stem cells. The University appealed the decision.
On the 28 November 2007, the matter reached a quiet resolution some fourteen years after the patent was filed. The University of Edinburgh withdrew the appeal during oral proceedings. The patent is now valid in the amended form resulting from the opposition procedure held in 2002.
The question of whether human embryonic stem cells are patentable is currently pending before the EPO's Enlarged Board of Appeal as case G2/06.