Translogic Technology, Inc. (“Translogic”) (plaintiff) obtained the ‘666 patent for its Transmission Gate Series Multiplexer (“TGM”)—a type of complex electrical circuit with multiple inputs, one or more control lines, and one output. The signals on the control lines select one of the various inputs to be passed to the output. In 1999, Translogic brought a patent infringement suit against Hitachi, Ltd. et al., (“Hitachi”) (defendant) in the U.S. District Court for the District of Oregon. During the ongoing litigation, Hitachi separately filed five requests with the U.S. Patent and Trademark Office (“USPTO”) for reexamination of Translogic’s patent. The requests were merged into a single proceeding and, in 2004 the USPTO rejected a number of Translogic’s patent claims on the basis that they would have been obvious at the time of the invention. Translogic appealed that decision to the USPTO’s Board of Patent Appeals and Interferences (“Board”). Also in 2004, a jury in the district court suit upheld the validity of Translogic’s patent. After a finding in 2005 that Hitachi had induced infringement, Translogic received damages totaling $86.5 million and the court entered a permanent injunction against Hitachi. Also in 2005, the USPTO Board upheld the rejection of the ‘666 patent as being obvious at the time of invention. In making its determination, the Board relied on art described in the Gorai technical article and the Weste textbook and found that although separately they did not illustrate Translogic’s TGM, together, a person of ordinary skill in the art would have figured out how to construct the TGM circuit using Weste and Gorai as guides. Translogic appealed.