By Allen Sokal and William Smith ( February 1, 2018, 11:10 AM EST) -- On Aug. 14, 2012, the U.S. Patent and Trademark Office published its final rule to implement the Leahy-Smith America Invents Act, including 37 C.F.R. § 42.73(d)(3)(i).[1] Section 42.73(d)(3)(i) provides: "A patent applicant or owner is precluded from taking action inconsistent with the adverse judgment [in proceedings before the Patent Trial and Appeal Board], including obtaining in any patent: (i) A claim that is not patentably distinct from a finally refused or canceled claim." Unlike § 42.73(d)(1), which prescribes the estoppel facing a petitioner in a post-grant proceeding and implements 35 U.S.C. §§ 315(e) and 325(e), no statutory provision specifically provides for the patent applicant or owner estoppel of § 42.73(d)(3)(i). This two-part article questions whether the PTO has exceeded its authority by issuing § 42.73(d)(3)(i). The first part considers the case law addressing § 42.73(d)(3)(i) and the statutory and some of the case law the PTO has relied on as authority for that provision. The second part will consider the remaining case law the PTO has relied on, namely that identified in Manual of Patent Examining Procedure § 706.03(w), which is titled "Res Judicata."...