Link to the Memorandum: USPTO Memorandum
On January 6, 2021, the United States Patent and Trademark Office (USPTO) issued a memorandum clarifying its indefiniteness analysis approach under 35 U.S.C. Section 112 in AIA post-grant proceedings. These proceedings include Reissues, Ex Parte Reexams, Inter Partes Reviews (IPRs), and Supplemental Examinations.1 The memorandum notes that until recently, the approaches for claim construction and indefiniteness applied by the USPTO in these proceedings differed from the way courts would apply the standards. In 2018, the USPTO changed its standard for claim construction from the Broadest Reasonable Interpretation (BRI) to the Phillips standard to harmonize the Patent Trial and Appeal Board's (PTAB's) proceedings relative to the federal courts. This new decision to adopt the Nautilus standard for indefiniteness appears to be catalyzed by the same factors. Indeed, the memorandum notes that both the office and the courts "generally approach the definiteness requirement of [Section] 112" during claim construction. Therefore they seem compelled to align the standards to provide uniformity (and avoid the potential for inconsistent judgments).2
The Statutory Basis for Definiteness
35 U.S.C. Section 112(b) states that "[t]he specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor" seeks to patent (emphasis added). The definiteness requirement's motivation is that indefinite claims do not give a clear warning about the patentee's property rights and do not adequately inform the public what the invention is.
In 2014, the Federal Circuit adopted the Office's approach to indefiniteness in In re Packard.3. Under this approach, the claims are sufficiently definite if "a person of ordinary skill in the relevant art would not consider the claim language unclear."4
In the same year as In re Packard, the Supreme Court held in Nautilus, Inc. v. Biosig Instruments, Inc., that a claim is indefinite if it "fails to inform, with reasonable certainty, those skilled in the art about the scope of the invention."5 This determination is made in light of the specification and the prosecution history.6 Despite the Supreme Court's determination that a different standard ought to be applied, the USPTO continued to apply the Packard standard. It reasoned that because of the BRI standard for claim interpretation and the "interactive process for resolving ambiguities," a different approach was warranted.7 It concludes that "aligning the indefiniteness approach in AIA post-grant proceedings will promote consistency and efficient decision making among coordinate branches of government."8
Confusion After the Switch from BRI
The Memorandum notes that since the USPTO switched from the BRI standard for these proceedings, there has been "confusion as to whether Nautilus or Packard applies."8 It noted that because of the confusion, parties have made arguments under both approaches.
 Covered Business Method Reviews (CBM Reviews) phased out in September of 2020.
 U.S.P.T.O. Memorandum, Approach to Indefiniteness under 35 U.S.C. § 112 in AIA Post-grant Proceedings, Jan. 6, 2021, at *5 (“Memorandum”).
 751 F.3d 1307 (Fed. Cir. 2014).
 MPEP Section 2173.02(III)(B).
 572 U.S. 898, 901 (2014).
 Ex parte McAward, Appeal 2015-006416, 2017 WL 3947829, at *4 (PTAB Aug. 25, 2017).
 Memorandum at 4 (citing BASF Corp. v. Ingevity South Carolina, LLC*, PGR2020-0037, Paper 19 at 12 (PTAB Sept. 10, 2020).
 Id. at 5.