Thursday, February 18, 2021 In deciding whether use of the term “passive link” to define a connection between a computer terminal and a fax machine rendered a patent claim indefinite, the US Court of Appeals for the Federal Circuit affirmed the district court’s finding of invalidity based on conflicting statements made by the patent owner during prosecution. Infinity Computer Products, Inc. v. Oki Data Americas, Inc., Case No. 20-1189 (Fed. Cir. Feb. 10, 2021) (Prost, C.J.) Infinity owns a patent directed to providing a circuit for interfacing a personal computer with a facsimile machine to enable the facsimile to be used as a scanner or a printer for a personal computer. The patent seeks to accomplish all of the objectives of a scanner or a printer in a simple, straightforward manner through the use of a circuit of highly simplified design and low cost. The patent claims recite that this functionality is accomplished “through a bi-directional direct connection via a passive link between the facsimile machine and the computer.” Infinity asserted the patent against Oki in district court.