The Federal Circuit Court of Appeals, in a divided ruling, has determined that Wrigley’s 2000 patent for menthol chewing gum was invalid because prior patents made Wrigley’s claimed invention obvious; thus, the court determined that Cadbury did not infringe Wrigley’s patent when it reformulated its chewing gum to include the compound claimed in Wrigley’s patent. Wm. Wrigley Jr. Co. v. Cadbury Adams USA LLC, Nos. 2011-1140, -1150 (Fed. Cir., decided June 22, 2012). The court also determined that Wrigley did not infringe Cadbury’s 1989 patent for menthol chewing gum because the compound used by Wrigley is not the equivalent of the compound described in Cadbury’s patent.
A dissenting judge argued that the majority applied the incorrect legal standard and improperly shifted the burden of proving the validity of Wrigley’s patent to Wrigley and erred in how it assessed the evidence of commercial success and copying by others in its determination of obviousness. According to the dissenter, substantial evidence, “much of it from Cadbury’s records,” showed that the compound used by Wrigley produced superior results and was a commercial success that Cadbury then copied to reverse its loss of sales to the new Wrigley gum. Insisting that these “secondary indicia of nonobviousness must be considered in deciding whether a prima facie case of obviousness has been presented,” the dissenting judge would have concluded that Wrigley’s patent was not obvious and thus valid.