YOSHIHIRO FUJIKAWA, MIKIO SUZUKI, HIROSHI IWASAKI, MITSUAKI SAKASHITA and MASAKI KITAHARA, Appellants, v. SOMPONG WATTANASIN, Appellee. YOSHIHIRO FUJIKAWA, MIKIO SUZUKI, HIROSHI IWASAKI, MITSUAKI SAKASHITA and MASAKI KITAHARA, Appellants, v. SOMPONG WATTANASIN, Appellee., 93 F.3d 1559

Summary

Appellants and appellees both invented a drug that inhibited cholesterol synthesis. However, appellees were granted priority over appellants as to the invention of the drug. Appellants challenged the finding, contending the date that appellees' invention was reduced to practice was erroneously determined. Appellants also argued that appellees had illegally suppressed or concealed their invention, and thus appellants should be given priority rights in the invention. The court held that the practical utility requisite to reducing an invention to practice could be shown in a chemical by proffering evidence of any pharmacological activity. As appellees had arguably met this burden based on the evidence, the court upheld the board's determination as to appellees' reduction to practice of the drug. The court then held that while evidence showed appellees were slow in prosecuting their claim for a patent, their delay did not rise to the level of patent suppression or concealment.