Metso Minerals v. Powerscreen International Distribution, Case No. 2011-1572, Slip Op. (Fed. Cir. May 14, 2013)
Metso Minerals (“Metso”) competes with Powerscreen International Distribution (“Powerscreen”) in the market for screeners – machines that sort rocks into sand, gravel, etc. Metso sued Powerscreen for infringement of U.S. Pat. No. 5,577,618. A jury in the Eastern District of New York found that Powerscreen’s screeners infringed multiple claims of the ‘618 patent.
During the trial Powerscreen asserted that the asserted claims of the ‘618 patent were invalid over two prior art screeners designed by Malachy Rafferty – the primary inventor of the ‘618 patent. However, the Court instructed the jury that any prior art reference considered for purposes of obviousness was fully operational and functional prior to the priority date of the ‘618 patent. Perhaps based on this instruction, the jury determined that the asserted claims of the ‘618 patent not invalid, and found that Powerscreen infringed. Powerscreen appealed and the Federal Circuit reversed.
The Court began by noting that a prior art reference need not be functional to be considered for purposes of obviousness. The Court also determined that the District Court’s instruction was not harmless, as it may have prevented the jury from considering certain prior art references. However, the Court did not stop there.
The Court then went on to hold that JMOL on the issue of obviousness should have been granted by the trial Court. In particular, the Federal Circuit noted that the prior art references established a prima facie case of obviousness, and then went on to explain that the claimed secondary factors of commercial success, unexpected results, and copying all failed to rebut the prima facie case of obviousness.