In American National v. Sleep Number Corporation, the Court of Appeals for the Federal Circuit (“CAFC”) affirmed the Patent Trial and Appeal Board’s (“Board”) decision to allow a patent owner to present proposed amended claims during inter partes review (“IPR”)proceedings that both respond to a ground of unpatentability and make other wording changes unrelated to the IPR proceedings.


Under 35 USC § 316(d), a patent owner may file one motion to amend a challenged patent by cancelling any challenged claims and/or proposing a reasonable number of substitute claims for each challenged claim. The amendments proposed by the patent owner must: (1) be supported in the original disclosure (and any earlier filed disclosure for which the benefit of filing date is sought); (2) respond to a ground of unpatentability involved in the IPR proceedings; and (3) not enlarge the scope of the claims of the patent or introduce new subject matter. 37 C.F.R. § 42.121. The petitioner carries the burden to demonstrate that the amendments proposed by the patent owner are unpatentable. Bosch Automotive Service Solutions, LLC v. Matal, 878 F.3d 1027, 1040 (Fed. Cir. 2017). 

In 2018, American National Manufacturing Inc. (“American National”) filed two petitions for IPR (Nos. IPR2019-00497 and IPR2019-00500). Each petition challenged a patent (U.S. Patent Nos. 8,769,747 and 9,737,154 respectively) owned by Sleep Number Corporation (“Sleep Number”).

In both proceedings, Sleep Number filed a motion to amend contingent on a finding that the challenged claims were unpatentable.  Sleep Number’s proposed amendments each included a limitation that addressed an unpatentability challenge raised by American National.  Some of the amendments further included additional edits that resolved issues under 35 U.S.C. § 112.


On appeal, American National argued that allowing a patent owner to refine claims or correct potential § 112 errors violated due process and the Administrative Procedure Act by allowing the patent owner and the Board to address concerns that were never germane to an IPR process.  Specifically, according to American National, it would be “asymmetr[ical]” and “unfair” to allow the patent owner to amend its claims to address § 112 concerns because a petition cannot challenge claims under § 112.

The CAFC, however, disagreed that allowing the patent owner to correct § 112 issues was unfair as petitioners are able to challenge proposed amended claims on grounds beyond §§ 102 and 103 (American National itself raised such challenges during the previous IPR proceedings).

The CAFC further supported its decision by discussing the Board’s holding in Lectrosonics, Inc. v. Zaxcom.  In Lectrosinics, the Board held “once a proposed claim includes amendments to address a prior art ground in the trial, a patent owner also may include additional limitations to address potential § 101 or § 112 issues, if necessary.” The Board reasoned that allowing these amendments “serves the public interest by helping to ensure the patentability of amended claims” and “helps ensure a ‘just’ resolution of the proceedings and fairness to all parties.”

The CAFC agreed with the Board’s reasoning and stated that it did not conflict with the American Invents Act, which only restricts amendments that enlarge the scope of the claims or introduce new matter. Thus, the CAFC held that so long as a proposed claim amendment does not enlarge the scope of the claims, does not add new matter, and responds to a ground of unpatentability in the proceeding, the patent owner may also make additional amendments to a claim without running afoul of the relevant statutes and regulation.