No. 92-1375. April 20, 1993. Robert P. Blackburn, Chiron Corp., Emeryville, CA, argued for appellant. With him on the brief were Debra A. Shetka and Thomas E. Ciotti, Morrison Foerster, Palo Alto, CA, and Donald S. Chisum, Morrison Foerster, Seattle, WA. Teddy S. Gron, Associate Sol., Office of the Sol., Arlington, VA, argued for appellee. With him on the brief was Fred E. McKelvey, Sol. Of counsel were John W. Dewhirst, Lee E. Barrett, Richard E. Schafer and Albin F. Drost. Appeal from the Patent