Congress enacted the America Invents Act in 2011 and ushered in a new era of adversarial proceedings in the Patent and Trademark Office (PTO). These proceedings, the inter partes review (IPR) and the post-grant review (PGR), are challenges to the validity of one or more claims in a single patent. Once a petitioner meets the statutory standards for institution of a "trial" before the PTO's Patent Trial and Appeal Board (PTAB), that would seem to be the end of the institution story and the beginning of an administrative determination of the patentability of the challenged claims. See 35 U.S.C. Sections 314, 324. But that is not always the case because the PTO director has discretion to deny institution. See Cuozzo Speed Technologies v. Lee, 579 U.S. 261, 273 (2016) ("And the agency's decision to deny a petition is a matter committed to the Patent Office's discretion.") This article is directed to such discretionary denials, and the difficulties arising from the lack of denial standards and from the gamesmanship of counsel, and the pending movement toward rulemaking to alleviate these concerns.