Minerva Surgical Inc. filed a reply brief on Wednesday to an opposition by Hologic Inc. and Cytyc Surgical Products LLC in the parties’ ongoing dispute on the Supreme Court stage over the future of assignor estoppel in patent litigation, arguing that the doctrine ought to be abandoned for the “paramount public interest in invalidating bad patents.”
Minerva was granted certiorari by the Supreme Court in early January after petitioning in September 2020 based on the question of “whether a defendant in a patent infringement action who assigned the patent, or is in privity with an assignor of the patent, may have a defense of invalidity heard on the merits,” according to the original petition. Shortly after Minerva filed its petition, Hologic filed a cross-petition, which was denied on Jan. 11. These higher-court proceedings grew from a modest 12-page complaint in the District of Delaware by the respondents, Hologic and Cytyc, alleging infringement of their patents covering NovaSure, a system for treating abnormal uterine bleeding.
Assignor estoppel is of interest to these parties — and, broadly, the world of intellectual property litigation — because it bars a patent’s original seller, or someone “in privity” with the seller, from later contesting the validity of the patent. The doctrine materialized in a Federal Circuit judgment that ruled that invalidity cannot be a defense in a patent action brought against the assignor of the patent or someone with a close relationship, in terms of the right to intellectual property, to the assignor.
Minerva contended that the Federal Circuit’s ruling, and reiterative subsequent judgments, contravene the Patent Act, which holds that litigants may invoke invalidity as a defense in patent infringement actions and does not expressly state whether invalidity may be utilized as a defense against an assignor or associate.
In its reply brief, Minerva argued that assignor estoppel “is an ill-conceived atextual doctrine developed by lower courts” with no history of being applied in Supreme Court decisions, “only limited” by the Court, harkening back to 1924’s Westinghouse Electric & Manufacturing Co. v. Formica Insulation Co. The respondents previously claimed that Formica reconciled assignor estoppel with the Patent Act; the petitioner disagreed, citing language from Supreme Court judgments that did not suggest the doctrine had been firmly settled, but rather “restricted” and “undermined.”
“There is no way to square Hologic’s view that Formica settled assignor estoppel into patent law with this Court’s own statements about the case,” Minerva said.
Along with arguing that Supreme Court’s judgments have reflected assignor estoppel’s settlement with the Patent Act, the respondents asserted that Congress has adopted the doctrine as compatible with the statute — but Minerva took issue with this characterization, saying it “would impose an impossible burden on Congress to police court decisions and seize for courts substantial policymaking authority even in the face of clear statutory language.”
Although the petitioner ultimately wants assignor estoppel wholly eliminated, it urged the court to constrain it through clear limits if the doctrine must survive.