The Harvard mouse, also known as "oncomouse" from the Greek word for tumour, was developed in the late 1980s. It is genetically altered so that it is susceptible to cancer after receiving relatively small amounts of carcinogens that do not normally affect other animals. Its developers claim that it helps clinical research by producing fast experimental results.
Harvard has been trying to patent the mouse in Canada since 1985. Its application was initially rejected by the country's commissioner for patents, who decided that the creation of the mouse did not meet the Canadian patent law's requirements of "manufacture" and "composition of matter".
A federal court in 1997 sided with the commissioner's decision. However, an appeals court ruled in 2000 that transgenic mammals, such as the oncomouse, constitute a composition of matter and therefore can be patentable under certain conditions.
The Supreme Court on 5th December 2002 rejected the patent application. In a five-to-four decision, the court ruled that transgenic mammals do not meet the Canadian Patent Act's definition of "composition of matter" and therefore cannot be considered as inventions. According to the court's interpretation, the definition was not intended to cover higher forms of life.
In its decision, the court also pointed out the lack of regulatory framework for the patentability of higher forms of life in Canada and that the issue was never litigated in the country before.
The court finally made it clear that its decision was based on technical and not moral considerations, and that the question of whether higher forms of life are patentable should be answered by the country's legislators.
The decision means that the animal itself cannot be patented. The process by which the mouse is developed can still be covered by Canadian patent law.
It is noted that the Harvard has owned US and Japan patents for the oncomouse for over a decade. The European Patent Office (EPO) has also granted a patent for the mouse. The EPO found that the mouse did not constitute an "animal variety", which cannot be patented under the EU Biotechnology Directive.
The Canadian Supreme Court's decision is available here