Case: 21-1321 Document: 88 Page: 1 Filed: 11/14/2022
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`
`
`United States Court of Appeals
`for the Federal Circuit
`______________________
`
`AMERICAN NATIONAL MANUFACTURING INC.,
`Appellant
`
`v.
`
`SLEEP NUMBER CORPORATION, FKA SELECT
`COMFORT CORPORATION,
`Cross-Appellant
`
`KATHERINE K. VIDAL, UNDER SECRETARY OF
`COMMERCE FOR INTELLECTUAL PROPERTY
`AND DIRECTOR OF THE UNITED STATES
`PATENT AND TRADEMARK OFFICE,
`Intervenor
`______________________
`
`2021-1321, 2021-1323, 2021-1379, 2021-1382
`______________________
`
`Appeals from the United States Patent and Trademark
`Office, Patent Trial and Appeal Board in Nos. IPR2019-
`00497, IPR2019-00500.
`______________________
`
`Decided: November 14, 2022
`______________________
`
`KYLE L. ELLIOTT, Spencer Fane, LLP, Kansas City,
`MO, argued for appellant. Also represented by BRIAN T.
`BEAR, KEVIN S. TUTTLE; ANDY LESTER, Oklahoma City, OK.
`
` RUFFIN B. CORDELL, Fish & Richardson PC,
`
`

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`AMERICAN NATIONAL v. SLEEP NUMBER CORPORATION
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`Washington, DC, argued for cross-appellant. Also repre-
`sented by ROBERT COURTNEY, MATHIAS WETZSTEIN
`SAMUEL, Minneapolis, MN; ANDREW S. HANSEN, ELIZABETH
`A. PATTON, LUKAS D. TOFT, Fox Rothschild LLP, Minneap-
`olis, MN; STEVEN A. MOORE, Moore IP Law PC, San Diego,
`CA; KECIA JANNELL REYNOLDS, Paul Hastings LLP, Wash-
`ington, DC.
`
` SARAH E. CRAVEN, Office of the Solicitor, United States
`Patent and Trademark Office, Alexandria, VA, argued for
`intervenor. Also represented by THOMAS W. KRAUSE,
`FARHEENA YASMEEN RASHEED; MEREDITH HOPE
`SCHOENFELD.
` ______________________
`
`Before STOLL, SCHALL, and CUNNINGHAM, Circuit Judges.
`STOLL, Circuit Judge.
`American National Manufacturing Inc. and Sleep
`Number Corp. each appeals the Patent Trial and Appeal
`Board’s final written decisions in two inter partes reviews.
`The Board issued mixed decisions in those proceedings, de-
`termining that some, but not all, of the challenged claims
`were not unpatentable. These appeals and cross-appeals
`involve two patents and numerous issues, including two on
`which the U.S. Patent and Trademark Office has inter-
`vened.
`is-
`these
`of
`four
`on
`focuses
`opinion
`Our
`sues: (1) whether the Board erred in permitting the patent
`owner to present proposed amended claims that both re-
`sponded to a ground of unpatentability and made other
`wording changes unrelated to the IPR proceedings;
`(2) whether those proposed amended claims were not ena-
`bled because of an alleged error in the specification;
`(3) whether those proposed amended claims should have
`been rejected for allegedly raising an inventorship issue;
`and (4) whether the Board inappropriately considered the
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`AMERICAN NATIONAL v. SLEEP NUMBER CORPORATION
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`petitioner’s sales data in its secondary considerations anal-
`ysis. For the below reasons, we affirm. Although we have
`thoroughly considered the other issues raised by both par-
`ties, we affirm the Board’s determinations regarding those
`issues without significant discussion.
`BACKGROUND
`I
`Sleep Number owns U.S. Patent Nos. 8,769,747 and
`9,737,154. Both patents describe systems and methods
`that purport to adjust the pressure in an air mattress “in
`less time and with greater accuracy” than previously
`known. ’747 patent col. 1 ll. 6–10.1 Conventional air bed
`systems have a control panel that allows a user to select a
`desired inflation setting for each air chamber in the air bed
`for optimal comfort and to change the inflation setting at
`any time, allowing for changes in the firmness of the bed.
`Id. at col. 1 ll. 13–25. The air chambers are in fluid com-
`munication with an air pump manifold. Id. at col. 3
`ll. 10–19, 46–51. The patents disclose adjusting pressure
`in an air bed “in less time and with greater accuracy” by
`measuring the air pressure inside the valve enclosure as-
`sembly instead of in the air chambers themselves, thus
`“eliminating the need to turn off the pump in order to ob-
`tain a substantially accurate approximation of the chamber
`pressure.” Id. at col. 1 ll. 6–10, col. 4 ll. 53–59.
`As the patents’ shared specification explains, the pres-
`sure control system computes and iteratively refines what
`the patents call “pressure adjustment factors” or “offsets”—
`the difference between the pressure in the valve enclosure
`assembly and the pressure in the bed’s air chambers. Id. at
`
`1 The ’154 patent is a continuation of the application
`that matured into the ’747 patent. Because the patents
`share a common specification, we refer only to the ’747 pa-
`tent specification unless otherwise specified.
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`AMERICAN NATIONAL v. SLEEP NUMBER CORPORATION
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`col. 2 ll. 26–31, col. 5 l. 9–col. 6 l. 7. The system then uses
`the pressure adjustment factor to determine what the “tar-
`get pressure” in the valve enclosure assembly must be for
`the air chamber to reach the user’s desired pressure set-
`point. Id. at col. 7 l. 51–col. 8 l. 59. The system adjusts the
`valve enclosure assembly pressure until it meets the target
`pressure, then re-tests the pressure in the air chamber.
`Id. at col. 8 l. 63–col. 9 l. 43. If the air chamber has still not
`reached the desired pressure setpoint, the system revises
`its pressure adjustment factor, using what the patents call
`an “adjustment factor error,” and tries again. Id. at col. 2
`ll. 28–31, col. 9 l. 44–col. 10 l. 51; see also id. Fig. 6 (de-
`scribing the process in flow diagram form). This process
`repeats until the air chamber reaches the desired pressure.
`The specification further explains that the process for
`determining the pressure adjustment factor varies depend-
`ing on whether the system is inflating or deflating the air
`chamber. To differentiate between the two processes, the
`patents describe using an additive offset (i.e., an offset that
`is added to the measured valve enclosure pressure) for in-
`flation and a multiplicative offset (i.e., an offset by which
`the measured valve enclosure pressure is multiplied) for
`deflation. Id. at col. 8 ll. 14–59, col. 9 ll. 51–61.
`Claim 1 of the ’747 patent recites:
`1. A method for adjusting pressure within an air
`bed comprising:
`providing or receiving an air bed, the air bed in-
`cluding an air chamber and a pump having a pump
`housing;
`selecting a desired pressure setpoint for the air
`chamber;
`determining an initial pressure within the pump
`housing;
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`calculating a pressure target based upon the de-
`sired pressure setpoint and a pressure adjustment
`factor, wherein an inflate pressure adjustment fac-
`tor is used to calculate the pressure target when
`the initial pressure within the pump housing is less
`than the desired pressure setpoint, and wherein a
`deflate pressure adjustment factor is used to calcu-
`late the pressure target when the initial pressure
`within the pump housing is greater than the de-
`sired pressure setpoint;
`adjusting pressure within the air chamber until a
`sensed pressure within the pump housing is sub-
`stantially equal to the calculated pressure target;
`determining an actual chamber pressure within
`the air chamber;
`comparing the actual chamber pressure to the de-
`sired pressure setpoint to determine the adjust-
`ment factor error; and
`modifying the pressure adjustment factor based
`upon the adjustment factor error.
`Id. at col. 12 ll. 43–67. Claim 1 of the ’154 patent is similar.
`See ’154 patent col. 13 ll. 11–29. Certain dependent claims
`of both patents require that the pressure adjustment factor
`be a multiplicative pressure adjustment factor. See
`’747 patent col. 13 ll. 8–13, col. 14 ll. 1–3 (claims 5, 6,
`and 13); ’154 patent col. 13 ll. 39–44, col. 14 ll. 46–49
`(claims 5, 6, and 15). Both patents also contain an inde-
`pendent claim requiring, among other things, a “pressure
`adjustment system for an air bed comprising . . . a pressure
`sensing means adapted to monitor pressure within the
`pump manifold.” ’747 patent col. 14 ll. 9–43 (claim 16);
`’154 patent col. 15 l. 16–col. 16 l. 18 (claim 20).
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`AMERICAN NATIONAL v. SLEEP NUMBER CORPORATION
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`II
`American National filed petitions for inter partes re-
`view challenging many claims of the ’747 and ’154 patents.
`In its petitions, American National asserted that most of
`the challenged claims would have been obvious over Gifft2
`in view of Mittal3 and Pillsbury,4 and that six of the de-
`pendent claims would have been obvious in further view of
`Ebel.5
`Gifft is owned by Sleep Number and incorporated by
`reference in the patents-in-suit. Gifft discloses an air bed
`system including a sealed valve enclosure assembly with
`an air pump for inflating and deflating air chambers to a
`desired pressure. Gifft col. 2 l. 56–col. 3 l. 2. Similar to the
`patents-in-suit, Gifft discloses monitoring the pressure
`within the valve enclosure instead of the air chamber itself
`while the air pump is in operation, which the system
`equates as being the actual pressure in the air chamber.
`Id. at col. 9 ll. 57–67 (claim 9); ’747 patent col. 1 ll. 48–64
`(describing prior art).
`Mittal describes a system for quickly reaching a de-
`sired air pressure in vehicle tires. Mittal Abstract, col. 8
`l. 65–col. 9 l. 9. Mittal discloses that there is often a lag
`between the time tire pressure is monitored and the time
`the pressure adjustment cycle ends; that is, the tire may
`reach the desired pressure before the pressure adjustment
`system detects it has done so. Id. at col. 2 ll. 32–47. To
`resolve this problem, Mittal’s system adjusts the desired
`pressure with additive offsets to compensate for these lags
`and to avoid “wasteful repeated pressure adjustment cy-
`cles.” Id. at col. 2 ll. 3–9, 16–26, col. 4 ll. 44–49.
`
`
`2 U.S. Patent No. 5,904,172.
`3 U.S. Patent No. 5,629,873.
`4 U.S. Patent No. 5,277,187.
`5 U.S. Patent Application Pub. No. 2007/0000559.
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`Pillsbury is directed to an automatic blood pressure
`cuff that measures a user’s blood pressure and employs a
`filter to “prevent dust, dirt, and other debris from clogging”
`the cuff’s air exit valve. Pillsbury Abstract, col. 8 ll. 25–63.
`The system detects and records the pressure in the cuff
`along with other data (including “oscillometric pulse am-
`plitudes” recorded at each cuff pressure as the cuff pressure
`reduces to zero) to “determine relatively accurately the
`user’s blood pressure.” Id. at col. 1 ll. 39–48. A data pro-
`cessor adjusts the cuff pressure measurement to compen-
`sate for any resistance added by the filter. Specifically, by
`using an additive offset, Pillsbury explains, its blood pres-
`sure cuff can provide an accurate measure of the air pres-
`sure inside the cuff while compensating for the added air
`resistance caused by build-up on the filter. Id. at col. 2
`ll. 40–54, col. 8 ll. 25–63.
`Ebel discloses a method for measuring the pressure in-
`side an air bag while filling or emptying the air bag. Ebel
`¶¶ 1, 7. Ebel explains that, because of what it calls “con-
`duit effects,” a pressure sensor cannot accurately measure
`the actual pressure in the air bag during inflation or defla-
`tion. Id. ¶ 3. Ebel explains that it is “only in the idle state,
`i.e., after a certain slow-down period[,] that the actual bag
`pressure can be determined by the pressure sensor.” Id.
`To compensate for these effects during inflation and defla-
`tion, Ebel proposes mathematical equations for calculating
`the actual pressure inside the air bag. Those equations use
`the air bag pressure measured by the pressure sensor as
`one input parameter and include both additive and multi-
`plicative components. Id. ¶¶ 4–7, 28–32.
`Before the Board, American National asserted that
`most of the challenged claims would have been obvious to
`the ordinarily skilled artisan over a combination of Gifft’s
`air bed system, with its measurement of the valve assem-
`bly pressure to approximate the air chamber pressure, and
`Mittal’s and Pillsbury’s use of additive offsets, or pressure
`adjustment factors. For the six dependent claims requiring
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`AMERICAN NATIONAL v. SLEEP NUMBER CORPORATION
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`a multiplicative pressure adjustment factor, American Na-
`tional argued these would have been obvious over a combi-
`nation of those three references as well as Ebel’s use of
`multiplicative offsets.
`In opposition, Sleep Number argued that: (1) evidence
`of industry praise and commercial success strongly sup-
`ported that the claims would not have been obvious;
`(2) American National had not adequately explained how
`and why the skilled artisan would have combined the as-
`serted references to meet the claim limitations; and
`(3) American National had not proposed a construction for
`the means-plus-function term “pressure sensing means” in
`violation of the Board’s rules.
`For industry praise, Sleep Number relied on two Amer-
`ican National internal business documents that Sleep
`Number asserted praised Sleep Number’s patents. The
`Board determined that one of these documents weighed
`“slightly in favor” of industry praise but that the other did
`not.
`For commercial success, Sleep Number relied on the
`commercial success not of its own products, but of Ameri-
`can National’s products—specifically, the products that
`Sleep Number had accused of infringement in a parallel
`district court proceeding. See J.A. 3647–49; see also First
`Am. Compl., Sleep No. Corp. v. Am. Nat’l Mfg., Inc.,
`No. 5:18-cv-00357 (C.D. Cal. Mar. 23, 2018). To support its
`arguments, Sleep Number sought discovery before the
`Board on American National’s sales of products sold with
`and without certain versions of source code that allegedly
`infringed claim 1. See J.A. 3004–05, 3050–55. The Board
`granted this motion, explaining that the evidence could
`help illuminate issues of nonobviousness, assuming Sleep
`Number could show a nexus between the relevant Ameri-
`can National products and the challenged patents.
`J.A. 3356–59. In its order, the Board noted that Sleep
`Number was not “seeking any admission of infringement,”
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`because its request simply sought a list of “products that
`include the allegedly infringing source code[] and those
`that do not.” J.A. 3359.
`In its Patent Owner Response, Sleep Number asserted
`American National products were coextensive with the
`challenged claims based in part on the testimony of Sleep
`Number’s experts, Drs. John Abraham and George Ed-
`wards. J.A. 3648; see also J.A. 4634–35 ¶ 29 (Dr. Abraham
`testifying that American National’s products “read on” the
`challenged claims); J.A. 4725–26 ¶ 41 (Dr. Edwards testi-
`fying the same).
`Based in part on this expert testimony, the Board
`found that Sleep Number had demonstrated a nexus be-
`tween American National’s increased sales numbers and
`its adoption of technology that “reads on” the challenged
`patents.6 See Am. Nat’l Mfg. Inc. v. Sleep No. Corp.,
`No. IPR2019-00497, Paper 114, at 91–92
`(P.T.A.B.
`Sept. 30, 2020) (’747 Decision); Am. Nat’l Mfg. Inc. v. Sleep
`No. Corp., No. IPR2019-00500, Paper 114, at 92–93
`(P.T.A.B. Sept. 30, 2020) (’154 Decision).7 Nevertheless,
`the Board determined that the evidence did not show that
`
`6 The Board’s original final written decisions stated
`that American National “does not refute the testimonies of
`Dr. Abraham and Dr. Edwards that” certain versions of the
`source code “fall within the claims of the [challenged] pa-
`tent[s] such that [American National]’s products using
`these versions infringe the claims.” ’747 Decision at 91
`(emphasis added); ’154 Decision at 92. After American Na-
`tional sought rehearing, the Board modified its final writ-
`ten decisions, changing the word “infringe” to “read on.”
`J.A. 143–44, 294–95.
`7 Although the Board issued separate final written
`decisions in these proceedings, the decisions are largely
`identical for many of the issues on appeal. In this opinion,
`we cite primarily to the ’747 Decision.
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`American National’s products “were commercially success-
`ful because of the merits of the claimed invention,” and not,
`for example, because of increased advertising, consumer
`recognition, or lowered price. ’747 Decision at 94. Thus,
`the Board gave Sleep Number’s evidence of commercial
`success “minimal probative weight.” Id.
`The Board ultimately resolved the proceedings with
`split decisions. For the six dependent claims requiring a
`multiplicative pressure adjustment offset, the Board deter-
`mined that American National had failed to establish un-
`patentability. See ’747 Decision at 139–40; ’154 Decision at
`145–50. Although the Board found that Ebel taught the
`use of multiplicative offsets, it also found that American
`National had not adequately shown why the skilled artisan
`would have applied Ebel’s multiplicative factors to the
`pressure targeting methods disclosed in Gifft as modified
`by Mittal and Pillsbury. See ’747 Decision at 81–84. Be-
`cause American National had not sufficiently articulated
`why the skilled artisan would have combined Ebel with the
`remaining references, the Board found American National
`had not established that the claims requiring multiplica-
`tive pressure adjustment factors were unpatentable as ob-
`vious.
`For the remaining claims, the Board found that Amer-
`ican National had proven they were unpatentable as obvi-
`ous. See id. at 140. For these claims, the Board credited
`American National’s expert, who testified that the ordinar-
`ily skilled artisan, presented with Gifft’s air bed pressure
`adjustment system, would have understood that by “im-
`proving the accuracy of [Gifft’s] pressure adjust cycles on
`an ongoing basis, the number of pressure adjustments nec-
`essary to reach a target pressure could be reduced.” See
`id. at 45 (citing J.A. 1148 ¶ 101). The Board rejected Sleep
`Number’s assertion that American National had failed to
`explain how or why a skilled artisan would combine the as-
`serted references and instead found that the skilled artisan
`would have a motivation to increase both speed and
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`AMERICAN NATIONAL v. SLEEP NUMBER CORPORATION
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`accuracy in Gifft’s system—and would have looked to tech-
`niques disclosed in other pneumatic systems references,
`such as Mittal and Pillsbury, to achieve these goals. See
`id. at 50–51. The Board therefore found that all claims not
`requiring a multiplicative pressure adjustment offset were
`unpatentable as obvious. See id. at 140.
`Finally, the Board rejected Sleep Number’s assertion
`that American National violated 37 C.F.R. § 42.104(b)(3),
`governing the contents of petitions, because American Na-
`tional’s petitions did not provide a sufficient construction
`for the means-plus-function term “pressure sensing
`means.” Although the Board acknowledged in both pro-
`ceedings that American National’s petitions did not “explic-
`itly state” how the means-plus-function term should be
`construed, it nonetheless determined that the petitions
`“fairly me[t] the requirements of” the regulation. ’747 De-
`cision at 24–25; ’154 Decision at 23–25.
`In each proceeding, Sleep Number filed a motion to
`amend contingent on a finding that the challenged claims
`were unpatentable. ’747 Decision at 104. Each of the pro-
`posed claims added the requirement of a multiplicative
`pressure adjustment factor, id. at 105–07, matching the
`claims that the Board had determined were not proven un-
`patentable. The proposed amended claims also included
`other non-substantive amendments, described by Sleep
`Number as made “for consistency with terms used in the
`industry and in related patents.” J.A. 3470; see also
`J.A. 3473–77. These non-substantive amendments in-
`cluded, for example, changing the term “pump housing” to
`“valve enclosure” and the term “chamber” to “bladder.”
`J.A. 3474, 3504–05.
`American National challenged the proposed amended
`claims. Among other things, it argued that: the proposed
`amendments did not respond to a ground of unpatentabil-
`ity and thus were legally inappropriate; the relevant spec-
`ification contained an error that rendered the claims
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`nonenabled; and the proposed amended claims lacked writ-
`ten description support and were indefinite.
`The Board rejected American National’s challenges to
`the proposed amended claims, finding that the amend-
`ments—which added the substantive limitation requiring
`a multiplicative pressure adjustment factor—responded to
`a ground of unpatentability in the proceedings. ’747 Deci-
`sion at 107–10. The Board also determined that the pro-
`posed amended claims were not unpatentable under
`35 U.S.C. § 112. Id. at 110–16. The Board thus granted
`Sleep Number’s contingent motions to amend. Id. at 120.
`American National appeals, and Sleep Number cross-
`appeals, from both final written decisions. We have juris-
`diction under 35 U.S.C. § 1295(a)(4)(A).
`DISCUSSION
`We review the Board’s legal conclusions de novo and its
`factual findings for substantial evidence. Univ. of Strath-
`clyde v. Clear-Vu Lighting LLC, 17 F.4th 155, 160
`(Fed. Cir. 2021). Obviousness is a legal question based on
`underlying findings of fact, including the existence of and
`weight assigned to any objective indicia of nonobviousness.
`Adapt Pharma Operations Ltd. v. Teva Pharms. USA, Inc.,
`25 F.4th 1354, 1364 (Fed. Cir. 2022). “The substantial ev-
`idence standard asks ‘whether a reasonable fact finder
`could have arrived at the agency’s decision,’ and ‘involves
`examination of the record as a whole, taking into account
`evidence that both justifies and detracts from the agency’s
`decision.’”
` OSI Pharms., LLC v. Apotex, Inc., 939
`F.3d 1375, 1381–82 (Fed. Cir. 2019) (quoting In re Gart-
`side, 203 F.3d 1305, 1312 (Fed. Cir. 2000)). We review stat-
`utory and constitutional issues de novo. MCM Portfolio
`LLC v. Hewlett-Packard Co., 812 F.3d 1284, 1287 (Fed. Cir.
`2015). But “[d]ecisions related to compliance with the
`Board’s procedures are reviewed for an abuse of discre-
`tion.” Ericsson Inc. v. Intell. Ventures I LLC, 901 F.3d
`1374, 1379 (Fed. Cir. 2018).
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`I
`We turn first to American National’s argument that
`the Board erred in permitting Sleep Number to present
`proposed amended claims that both responded to a ground
`of unpatentability involved in the proceedings and made
`other changes not responsive to an unpatentability ground.
`In its motion to amend, Sleep Number stated that some of
`its proposed amendments (like changing the phrase “pump
`housing” to “valve enclosure”) were made “to achieve con-
`sistency and accuracy in terminology and phrasing”
`throughout the patent family. J.A. 3474, 3504–05. Be-
`cause this purpose was not directly “aimed at responding
`to a ground of unpatentability at issue in” the IPR proceed-
`ing, as required by 37 C.F.R. § 42.121, American National
`argues on appeal, as it did below, that these proposed
`amendments were improper.
`In considering this issue, the Board has previously de-
`termined that § 42.121 “does not require . . . that every
`word added to or removed from a claim in a motion to
`amend be solely for the purpose of overcoming an instituted
`ground.” Lectrosonics, Inc. v. Zaxcom, Inc., No. IPR2018-
`01129, 2019 WL 1118864, at *2 (P.T.A.B. Feb. 25, 2019)
`(precedential). Instead, “once a proposed claim includes
`amendments to address a prior art ground in the trial, a
`patent owner also may include additional limitations to ad-
`dress potential § 101 or § 112 issues, if necessary.” Id. Al-
`lowing these amendments, the Board has explained,
`“serves the public interest by helping to ensure the patent-
`ability of amended claims” and “helps ensure a ‘just’ reso-
`lution of the proceedings and fairness to all parties.”
`Id. (quoting 37 C.F.R. § 42.1(b)).
`We agree with the Board’s thoughtful analysis of this
`issue in Lectrosonics. Indeed, nothing in the America In-
`vents Act (AIA) or the Board’s regulations precludes a pa-
`tent owner from amending a claim to both overcome an
`instituted ground and correct other perceived issues in the
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`claim. The AIA explicitly restricts patent owner amend-
`ments in only two ways: amendments may not enlarge the
`scope of the claims or introduce new matter. 35 U.S.C.
`§ 316(d)(3). The Board’s regulations add another re-
`striction: amendments must respond to a ground of un-
`patentability involved in the proceeding.
` 37 C.F.R.
`§ 42.121(a)(2)(i). As we have previously explained, the Di-
`rector introduced this regulation “merely to ensure that the
`proposed amendment had a minimal level of relevancy to
`the IPR.” Aqua Prods., Inc. v. Matal, 872 F.3d 1290, 1317
`(Fed. Cir. 2017) (en banc) (plurality opinion) (citing
`Changes to Implement Inter Partes Review Proceedings,
`77 Fed. Reg. 48,680, 48,705 (Aug. 14, 2012)). Thus, 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 regula-
`tion.
`American National argues that allowing a patent
`owner to refine claims or correct potential § 112 errors “in-
`vites a violation of due process and the Administrative Pro-
`cedure Act, by allowing the patent owner and the Board to
`address concerns that may be proper for [an] examination
`or reexamination proceeding, but that were never germane
`to an IPR process.” Appellant’s Br. 69–70. Specifically, ac-
`cording to American National, because a petition cannot
`challenge claims under § 112, it would be “asymmetr[ical]”
`and “unfair” to allow the patent owner to amend its claims
`to address § 112 concerns. We are not convinced. As we
`have previously explained, the petitioner can challenge the
`proposed amended claims on grounds beyond §§ 102 and
`103, including under § 112. See Uniloc 2017 LLC v. Hulu,
`Inc., 966 F.3d 1295, 1305–07 (Fed. Cir. 2020) (holding that
`petitioners may challenge proposed substitute claims out-
`side of §§ 102 and 103); Samsung Elecs. Am. v. Prisua
`Eng’g Corp., 948 F.3d 1342, 1352 (Fed. Cir. 2020) (“[T]he
`
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`AMERICAN NATIONAL v. SLEEP NUMBER CORPORATION
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`15
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`Board’s authority with respect to new and amended claims
`necessarily extends to other possible grounds of unpatent-
`ability, in particular, a failure to comply with section
`112.”). Indeed, American National did so in its oppositions
`to Sleep Number’s motions to amend in these IPRs. Ac-
`cordingly, we discern no unfairness or asymmetry in the
`Board’s granting of the motion to amend.
`In this case, each of Sleep Number’s proposed substi-
`tute claims included an amendment responsive to a ground
`of unpatentability raised in the proceedings. Specifically,
`each proposed substitute claim added a limitation requir-
`ing a multiplicative pressure adjustment factor—mirroring
`the claims that the Board had determined were not un-
`patentable. ’747 Decision at 105–07 (proposed substitute
`claims); see also J.A. 3474–77, 3504–08. Because each pro-
`posed substitute claim included at least one responsive
`narrowing limitation, Sleep Number was free to include
`other amendments, including any addressing perceived
`§§ 101 and 112 issues. American National was free to chal-
`lenge these proposed claims, as it did in both proceedings.
`And the Board was free to determine whether the proposed
`claims were unpatentable under §§ 101, 102, 103, and 112.
`We thus see no error in the Board’s decision to consider
`Sleep Number’s proposed substitute claims.
`II
`We turn next to American National’s enablement argu-
`ment. Section 112(a) requires, among other things, that
`the specification enable a skilled artisan to make and use
`the claimed invention. In re Wands, 858 F.2d 731, 735
`(Fed. Cir. 1988). “Whether a claim satisfies the enable-
`ment requirement of 35 U.S.C. § 112 is a question of law
`that we review without deference, although the determina-
`tion may be based on underlying factual findings, which we
`review for clear error.” Amgen Inc. v. Sanofi, Aventisub
`LLC, 987 F.3d 1080, 1084 (Fed. Cir. 2021) (citing Alcon
`Rsch. Ltd. v. Barr Lab’ys Inc., 745 F.3d 1180, 1188
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`Case: 21-1321 Document: 88 Page: 16 Filed: 11/14/2022
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`16
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`AMERICAN NATIONAL v. SLEEP NUMBER CORPORATION
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`(Fed. Cir. 2014)). American National argues that an ad-
`mitted error in the specification of the application to which
`the ’747 and ’154 patents claim priority necessarily means
`that the proposed amended claims are not enabled. Appel-
`lant’s Br. 70–71. We disagree.
`There is undisputedly an error in the specification of
`the challenged patents. ’747 Decision at 113–14. The spec-
`ification states:
`Updated Inflate Adjustment Factor = (Manifold
`Pressure from Step 168) – (Pressure Setpoint
`from Step 106)
`Id. at 114 (citing J.A. 10163 ¶ 67) (emphasis added to erro-
`neous portion). Both parties agree this equation should in-
`stead read:
`Updated Inflate Adjustment Factor = (Manifold
`Pressure from Step 168 176) – (Pressure Set-
`point from Step 106)
`Id. (citing J.A. 10085 ¶ 20) (emphasis added to corrected
`portion). Sleep Number’s expert testified that the skilled
`artisan would understand that this “is a typographical er-
`ror inconsistent with the remainder of the disclosure” in
`the specification. Id. (citing J.A. 10085 ¶ 20). This testi-
`mony is supported by the specification. For example, im-
`mediately before the equation, the specification correctly
`explains that the “manifold pressure sampled in step 176”
`is compared to the “setpoint pressure” of step 106.
`J.A. 10162 ¶ 63; see also, e.g., ’747 patent col. 9 ll. 33–38
`(discussing the “manifold pressure sampled in step 176”).
`On this record, the Board reasonably found that the error
`was a “mistake or typographical error,” ’747 Decision
`at 114, and thus that American National had not shown
`the proposed claims were unpatentable for lack of enable-
`ment, id. at 115.
`In an analogous case, we affirmed a district court’s
`finding that a patent was enabled, despite a calculation
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`AMERICAN NATIONAL v. SLEEP NUMBER CORPORATION
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`17
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`error in the specification. PPG Indus. v. Guardian Indus.
`Corp., 75 F.3d 1558 (Fed. Cir. 1996). In PPG Industries,
`the specification described how to make the patented “solar
`control” glass composition but included test results and cal-
`culations rendered “artificially high” by a software error.
`Id. at 1563–64. The district court had found that the error
`was “easily detectable by anyone who was skilled in the
`art.” Id. at 1564. And, we explained, the remainder of the
`specification described the process with sufficient detail to
`“indicate[] to one skilled in the art how” to make such a
`glass composition. Id. at 1565. We affirmed the district
`court’s finding that the patent was enabled, despite the er-
`ror, because the skilled artisan would, “[i]n light of the
`guidance provided by the specification” as a whole, be ena-
`bled to make and use the claimed invention. Id. at 1564–
`65. The same rationale and conclusion apply here.
`American National nonetheless argues that this error
`was not obvious because it was not noted during the origi-
`nal examination process. And because the equation in the
`specification, as erroneously w