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Diamond Scientific Co. v. Ambico, Inc.
United States Court of Appeals for the Federal Circuit
848 F.2d 1220, 6 U.S.P.Q.2d (BNA) 2028 (Fed. Cir. 1988)
Dr. Clarence Welter (defendant) founded Ambico, Inc. (defendant). Prior to forming Ambico, while Welter was employed by Diamond Scientific Co. (Diamond) (plaintiff), he invented a vaccine for pigs. Welter filed a patent application and, before the application was granted, assigned all rights in the patents to Diamond. The assignment was conducted in exchange for valuable consideration. Welter executed an oath that asserted he believed he was the first and only inventor of the vaccine, the vaccine was never previously known or used, and the vaccine had not already been patented or described in a publication in any country. Diamond was eventually given three patents related to the vaccine. Ambico started producing and selling similar pig vaccines after Diamond received the patents. Diamond filed a patent-infringement case in federal court against Ambico and Welter, asserting Ambico’s vaccines infringed on the three vaccine patents assigned by Welter to Diamond. Ambico and Welter filed an answer that included the affirmative defense of patent invalidity for each of the three patents. Diamond filed a motion to strike the three affirmative defenses, asserting the doctrine of assignor estoppel. The district court granted the motion to strike, and Ambico and Welter appealed.
Rule of Law
Holding and Reasoning (Davis, J.)
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