Kenyon successfully represented Teva on appeal to the US Court of Appeals for the Federal Circuit in a patent infringement litigation concerning Teva's generic equivalent to Eli Lilly's cancer drug Gemzar®. The Federal Circuit affirmed the Southern District of Indiana court's ruling in favor of Teva that Lilly was collaterally estopped from denying that its method-of-use patent was invalid. That decision provided Teva with an exclusive right to sell generic versions of Gemzar® for 180 days. Case number 06-238 (2011).