DSL Dynamic Sciences Ltd. v. Union Switch & Signal, Inc.

Two separate inventive entities claimed priority of invention of clamps for coupling equipment to railway cars. Hartmut Schmid claimed he conceived of the idea and reduced it to practice in Canada before filing a US application in September 1983. DSL Dynamic Sciences Ltd. (DSL) (plaintiff) was assigned the patent that issued from Schmid’s application. Robert Blosnick and another inventor claimed they conceived of the invention, in the US, in January 1983 and reduced it to practice no later than May 1983. Union Switch & Signal, Inc. (Union Switch) (defendant) was assigned the patent that issued from Blosnick’s application. The patent office declared interference between the Schmid patent and Blosnick application in 1996, and Union Switch offered tests of a prototype of Blosnick’s invention in April and May of 1983 to claim priority of invention. Three tests in May concluded the clamp performed satisfactorily for over 700 miles, at speeds exceeding 50 miles per hour, when it was used to couple various measurement devices to train cabooses. The clamp’s performance was documented by pictures and reports including data that the clamp was able to withstand forces in excess of 15 Gs (gravitational force) Despite DSL’s argument that the Blosnick prototype did not fall within the claimed scope because the clamp was intended to be coupled to a freight car versus a caboose, the Board of Patent Appeals and Interference (board) (defendant) found Union Switch established priority of invention by establishing an invention date no later than May 1983. This district court affirmed the board’s determination, finding no definite and thorough error despite DSL’s attempt to offer new evidence that cabooses have better suspensions than freight cars that can experience shocks up to 20 Gs and that products made from the prototype and sold in 1985 were found unsuitable for their intended use. DSL appealed.