Minerva Surgical, Inc. v. Hologic, Inc., 594 U.S. ___ (2021), was a United States Supreme Court case dealing with the principle of assignor estoppel and its application.

Csaba Truckai founded the company NovaCept, which invented the NovaSure medical system, which detects perforations in the uterus through the usage of Carbon Dioxide gas.

[1][2] Truckai left NovaCept to found his own company, Minerva, Inc. and received permission to commercially distribute an Endometrial Ablation System.

In a 5–4 decision, the Supreme Court re-affirmed the principle of assignor estoppel, and rejected the argument of Minerva that the doctrine was repealed through the Patent Act of 1952.

Justice Barrett argued in the principal dissent that the Patent Act of 1952 precludes the principle of Assignor estoppel.