By Eldora Ellison and Jacob Rothenberg (September 26, 2017, 12:09 PM EDT) -- In implementing the America Invents Act's objective of improving patent quality, the U.S. Patent and Trademark Office created regulations that preclude a patent owner from obtaining additional patent claims that are too closely related to any claims for which the patent owner received an adverse judgment in a post-grant challenge, such as an inter partes review, post-grant review or covered business method patent review. Specifically, the USPTO codified the doctrine of patent owner estoppel under 37 C.F.R. §42.73(d)(3), precluding a patent owner from taking action at the USPTO inconsistent with an adverse judgment. In practice, patent owner estoppel may prevent a patent owner from subsequently obtaining patent claims that are not "patentably distinct" from claims lost in the post-grant challenge. Thus, an adverse judgment at the Patent Trial and Appeal Board may negatively impact the future of a patent owner's portfolio of pending applications. The potential impact of patent owner estoppel should be considered in light of the claim cancellation rate: Approximately 65 percent of final decisions have cancelled all instituted claims, and approximately 17 percent have canceled some of the instituted claims.[1]...