Oncomouse

The OncoMouse or Harvard mouse is a type of laboratory mouse (Mus musculus) that has been genetically modified using modifications designed by Philip Leder and Timothy A Stewart of Harvard University to carry a specific gene called an activated oncogene (v-Ha-ras under the control of the mouse mammary tumor virus promoter). The activated oncogene significantly increases the mouse’s susceptibility to cancer, and thus makes the mouse suitable for cancer research. The rights to the invention were owned by DuPont until recently. The USPTO found that the patent expired in 2005, which means that the Oncomouse is now free for use by other parties (although the name is not, as "OncoMouse" is a registered trademark).

Patent applications on the OncoMouse were filed back in the mid-1980s in numerous countries such as in the United States, in Canada, in Europe through the European Patent Office (EPO) and in Japan.

In Canada, the Supreme Court in 2002 rejected the patent in Harvard College v. Canada (Commissioner of Patents), overturning a Federal Court of Appeal verdict which ruled in favor of the patent. However, on 7 October 2003, Canadian patent 1,341,442 CA 1341442  was granted to Harvard College. The patent was amended to omit the "composition of matter" claims on the transgenic mice. The Supreme Court had rejected the entire patent application on the basis of these claims, but Canadian patent law allowed the amended claims to grant under rules that predated the General Agreement on Tariffs and Trade, and the patent remains valid until 2020.

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Wikipedia