Amgen (P) appealed from an affirmation of a decision where the judge concluded that Hoechst’s (Ds) process did not infringe P’s patent.
FACTS: P discovered a method of producing erythropoietin (EPO), useful for the treatment of anemia, by using recombinant DNA technology. P's method involved introducing an exogenous DNA sequence coding for EPO into a host cell. P was granted a European patent (EP 0148605B2). Transkaryotic Therapies, Inc. (D) developed a method involving inserting an endogenous DNA sequence coding for EPO driven by an exogenous upstream control sequence into a human host cell. P claimed patent infringement and Ds sought a declaration of noninfringement and a revocation of the patent on grounds of insufficiency. Once the sequence of the EPO gene had been discovered, it was possible to make it by methods of recombinant DNA technology which were well known in 1983. The essential difference between P and Ds' methods is that the former is made by an exogenous DNA sequence coding for EPO which has been introduced into a host cell and the latter is made by an endogenous DNA sequence coding for EPO in a human cell into which an exogenous upstream control sequence has been inserted. The High Court found one of P's claims invalid and another valid and infringed. The judge construed the claim terms in a “literal” manner. The Court of Appeal held that both claims were valid, but that neither was infringed. Both sides appealed.