AMGEN INC., Plaintiff-Cross Appellant, v. HOECHST MARION ROUSSEL, INC. (now known as Aventis Pharmaceuticals Inc.) and TRANSKARYOTIC THERAPIES, INC., Defendants-Appellants., 314 F.3d 1313

Summary

The holder owned numerous patents directed to the production of erythropoietin, a naturally occurring hormone that controlled the formation of red blood cells in bone marrow. The patent holder marketed and sold a highly successful commercial embodiment of the patented erythropoietin. The holder sought to impede the alleged infringers from commercializing a competitive erythropoietin product. The alleged infringer argued that the patents in suit were all unenforceable, that the district court's claim construction was erroneous, and alternatively, if that claim construction was correct, that the court's validity determinations were erroneous. The instant court held that the district court's finding that the patent holder satisfied the written description requirement was not clearly erroneous. The court reasoned that the district court properly weighed the testimony and found that the evidence showed that the descriptions adequately described to those of ordinary skill in the art in 1984 ...