Mealey's (April 23, 2020, 1:42 PM EDT) -- WASHINGTON, D.C. — The Federal Circuit U.S. Court of Appeals on April 22 upheld a Delaware federal judge’s determination that assignor estoppel does not bar an assignor from relying, in district court, on an affirmance of a Patent Trial and Appeal Board invalidating various claims of the patent (Hologic Inc., et al. v. Minerva Surgical Inc., No. 19-2054, Fed. Cir., 2020 U.S. App. LEXIS 12882)....