By Eric M. Fraser
on April 23, 2021
at 5:45 p.m.
Matthew Wolf argues for Hologic, Inc. (Art Lien)
The judges investigated possible ways to curtail patent applicant Estoppel’s doctrine during a hearing at Minerva Surgical Inc. v Hologic Inc. on Wednesday.
The teaching works like this. An inventor files a patent application for an invention and transfers the patent rights to an assignee – possibly for money from the assignee or possibly under a contract with the inventor’s employer. After a patent has been granted, the applicant claims that the inventor infringed the patent. In the patent infringement suit, the inventor wants to argue that the patent is invalid. The doctrine of the referrer estoppel prevents the inventor from questioning the validity. It arises from a concern that any assignment of patent rights involves implicit representations of patentability, and the inventor should not be able to contradict such representations and undermine the value of the assigned patent rights.
Minerva, who makes medical devices, seeks to abolish the doctrine. It has been accused of infringing the patented technology invented by the company’s founder and wants to avoid liability for patent infringement. Hologic, a competitor, is trying to uphold the doctrine. It owns the assigned rights to the patent and is suing Minerva for patent infringement.
Although the dispute did not result in a strong consensus, the judges either appeared unwilling to abandon the doctrine altogether or to keep it as it is. Most of the arguments concerned the middle ground by which the doctrine could continue to exist in its narrow form. Six of the nine judges asked Minerva or Hologic about ways to curtail the doctrine, and five asked specifically about the federal government’s proposed restrictions that I covered earlier this week.
Robert Hochman, who spoke out in favor of Minerva, called the assignor estoppel a “doctrine dinosaur” and opened with an appeal to the textualists: “The patent law does not provide for an assignor estoppel and never did.” But the judges did not seem ready to to reject the teaching altogether. Hochman asked several questions about why the court should abandon a doctrine that the court has recognized for nearly a century.
Judge Elena Kagan asked about the “core application of Assignor Estoppel” where an inventor gets a patent, sells the patent and then argues that the invention is obvious and not patentable. Hochman acknowledged that this hypothetical inventor cannot invoke disability, but tried to rely on other teachings to explain why.
Judge Clarence Thomas took a different approach, pointing out that patent law does not mention either a claim exclusion or an issue exclusion, but these doctrines preclude certain arguments in patent litigation.
Morgan Ratner spoke out in favor of the federal government, which submitted its own brief from a friend of the court, but did not support any party. The judges urged Ratner to determine where the government’s version of the doctrine had come from. As Judge Neil Gorsuch put it, “No court has ever used the version of estoppel that you are now proposing.” Or from Judge Stephen Breyer: “I can understand that it will be abolished. I can understand keeping it. But when I narrow it down, I find difficulty in figuring out the right way to do that. “
Matthew Wolf spoke out in favor of Hologic. Wolf argued mainly that the rigid decisions justified maintaining the doctrine. But the judges urged Wolf how firmly the teaching really is anchored. Chief Justice John Roberts suggested that “it is not the strongest rigid decision-making argument” given the Supreme Court decisions that characterize the doctrine as a failure.
The judges also urged Hologic to understand why the doctrine should apply in all cases. The judges in particular appeared concerned about the general scenario in which an employee signs a general assignment of all inventions to her employer as part of her employment contract. According to the current version of the doctrine, the employee could be prohibited from ever questioning the validity of a patent pursued by her employer. The judges were also concerned about situations where there is no inconsistency between the referring physician’s implicit representation of validity and the referring physician’s eventual disability challenge. This situation can arise, for example, if an assignee expands the scope of the patent after the assignment and receives a patent that is wider than what the assignee believed was patentable at the time of the assignment.
The judges have to sort out several main issues: the role of the rigid decision, the uncertainty about the client’s decoupling in the court’s own cases, and setting reasonable boundaries for doctrine. Although the judges did not appear to be anxious to abandon the client estoppel, they are unlikely to adopt a broad version of the oppressed doctrine.