1970s. In this arrangement with DuPont, Harvard would own any patents that might arise from Leder's research, but DuPont would be entitled to exclusive license on any and all such properties.
During the next 2 years, exploiting the transgenic technology developed by Gordon and Ruddle, Leder and his collaborators developed the oncomouse by inserting the MYC oncogene attached to a specific promoter into the embryo of a normal mouse. The promoter is a mouse mammary-tumor virus-promoter that is expressed directly in breast epithelial cells, and mice with this oncogene reproducibly develop breast cancer. Leder 's work was not aimed at devising a patentable product; it derived from research on Burkitt's lymphoma that he had begun at the National Institutes of Health. However, once his research was successful, Leder recognized that it might have commercial possibility.
Near the end of 1983, Leder brought his mice to the attention of the Office of Technology Licensing and Industry-Sponsored Research at the Harvard Medical School, which had recently been created in line with Harvard's thrust to commercialize the results of research done in its laboratories. The office assembled a small group, including Leder, several DuPont intellectual-property lawyers, and Paul Clark, a patent attorney who was Harvard's principal outside patent counsel. Clark believed that it was important to patent the mice to give Harvard and DuPont, which was the licensee, all the legal rights to which they were entitled. He further believed that claims on methods of using the mice or on plasmids, although of some importance, would not have protected the invention adequately by themselves. The reasoning among patent lawyers is that it is best to protect the product as well as the processes used to create it, to prevent competitors who are using different processes from trying to develop similar but competitive products.
Clark also saw that Leder's transgenic animals were new compositions of matter made by humans –like the bacteria on which the Supreme Court had ruled in 1980. Genes are matter; they are DNA. The oncomouse does not occur naturally; it was made by humans. It was therefore a new composition of matter because a human being had inserted a new chemical into the genome of the mouse. Consequently, it could be patented.
On June 22, 1984, on behalf of Harvard, Clark filed an application for a patent on Leder's invention. The main utilities that he claimed were straightforward but very broad. They included the use of such animals as sources of malignant or protomalignant tissue for cell culture and as living systems on which to test chemicals for carcinogenicity or, in the case of substances such as vitamin E, for the power to prevent cancers.
Clark had not been conservative in what he claimed as the actual invention. It was not simply a transgenic mouse with an activated MYC gene; it was any transgenic mammal, excluding human beings, that contain in all its cells an activated oncogene that had been introduced into it or an ancestor at