The doctrine of inequitable conduct in patent law has a long and vexing history. While it is sometimes mistakenly conflated with the United States Patent and Trademark Office’s Rule 56, the doctrine is actually a purely equitable one established by the Supreme Court in 1945—and not revisited by it since then. This Article re-establishes the roots and proper context of the doctrine, while tracing its confused interactions with Rule 56 over the ensuing decades. The Article reaffirms the necessary balancing act between over and under disclosure of references during patent prosecution, and the inverse sliding scale relationship of materiality and intent to deceive for courts’ invocation of the doctrine as a patent litigation defense rendering the patent unenforceable. It concludes by proposing a “damages-at-law only” litigation tactic by patent owners to preclude the use of the doctrine by defendants.
Sean M. O’Connor, Defusing the “Atomic Bomb” of Patent Litigation: Avoiding and Defending Against Allegations of Inequitable Conduct After McKesson et al., 9 J. Marshall Rev. Intell. Prop. L. 330 (2009)