? The doctrine was narrowed by Diamond Scientific Co. v. Ambico, Inc., 848 F.2d 1220 (Fed. Cir. 1988), in which the court held that in some circumstances equity may outweigh the public-policy reasons behind the estoppel doctrine. [Cases: Patents 129(2). C.J.S. Patents ¡ì 227.]
Patents. Estoppel barring someone who has assigned the rights to a patent from later attacking the patent’s validity. Westinghouse Elec. & Mfg. Co. v. Formica Insulation Co., 266 U.S. 342, 45 S.Ct. 117 (1924).