Case: 18-1763   Document: 134     Page: 1   Filed: 07/31/2020




    United States Court of Appeals
        for the Federal Circuit
                  ______________________

    AMERICAN AXLE & MANUFACTURING, INC.,
               Plaintiff-Appellant

                             v.

  NEAPCO HOLDINGS LLC, NEAPCO DRIVELINES
                    LLC,
             Defendants-Appellees
            ______________________

                        2018-1763
                  ______________________

     Appeal from the United States District Court for the
 District of Delaware in No. 1:15-cv-01168-LPS, Chief Judge
 Leonard P. Stark.
                   ______________________

            OPINION ISSUED: October 3, 2019
            OPINION MODIFIED: July 31, 2020 *
                 ______________________

     JAMES RICHARD NUTTALL, Steptoe & Johnson LLP, Chi-
 cago, IL, argued for plaintiff-appellant. Also represented
 by JOHN LLOYD ABRAMIC, KATHERINE H. JOHNSON; ROBERT
 KAPPERS, Steptoe & Johnson, LLP; CHRISTOPHER ALAN
 SUAREZ, Washington, DC.



     *   This opinion has been modified and reissued
 following a petition for rehearing filed by Appellant.
Case: 18-1763      Document: 134     Page: 2    Filed: 07/31/2020




 2        AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                       LLC




    DENNIS J. ABDELNOUR, Honigman LLP, Chicago, IL, ar-
 gued for defendants-appellees. Also represented by J.
 MICHAEL HUGET, SARAH E. WAIDELICH, Ann Arbor, MI.

     SCOTT A. M. CHAMBERS, Porzio, Bromberg & Newman,
 PC, Washington, DC, for amici curiae Christopher Frerk-
 ing, Christopher Michael Holman, David Lund, Walter
 Matystik, Adam Mossoff, Kristen J. Osenga, Michael
 Risch, Mark F. Schultz, Ted M. Sichelman, Brenda M. Si-
 mon, Jonathan Stroud, David O. Taylor. Also represented
 by MATTHEW ZAPADKA, Bass, Berry & Sims, PLC, Washing-
 ton, DC.
                 ______________________

     Before DYK, MOORE, and TARANTO, Circuit Judges.
         Opinion for the court filed by Circuit Judge DYK.
      Dissenting opinion filed by Circuit Judge MOORE.
 DYK, Circuit Judge.
     American Axle & Manufacturing, Inc. (“AAM”) sued
 Neapco Holdings LLC and Neapco Drivelines LLC (collec-
 tively, “Neapco”) alleging infringement of claims of U.S. Pa-
 tent No. 7,774,911 (“the ’911 patent”). 1 The parties filed
 cross-motions for summary judgment as to the eligibility of
 the asserted claims of the ’911 patent under 35 U.S.C.


     1   AAM’s complaint alleged infringement of two other
 patents—U.S. Patent Nos. 8,176,613 (“the ’613 patent”)
 and 8,528,180 (“the ’180 patent”). During claim construc-
 tion, the district court held the asserted claims of the ’613
 patent indefinite. Neapco Mot. for Summ. J. 3, American
 Axle & Manuf., Inc. v. Neapco Hldgs. LLC, No. 15-01168
 (D. Del. Aug. 11, 2017), ECF No. 164. AAM also withdrew
 the asserted claims of the ’180 patent. Id. Neither the ’613
 nor the ’180 patent is at issue on appeal.
Case: 18-1763    Document: 134      Page: 3    Filed: 07/31/2020




 AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS            3
 LLC


 § 101. The district court granted Neapco’s motion and held
 that the asserted claims are ineligible under § 101. We af-
 firm in part and vacate and remand in part.
                        BACKGROUND
                               I
      The ’911 patent generally relates to a method for man-
 ufacturing driveline propeller shafts (“propshafts”) with
 liners that are designed to “attenuat[e] . . . vibrations
 transmitted through a shaft assembly.” ’911 patent, col. 1,
 ll. 6–7. Propshafts are “employed [in automotive vehicles]
 to transmit rotary power in a driveline.” Id. col. 1, ll. 38–
 39. Because these propshafts are typically made of a “rel-
 atively thin-walled steel or aluminum tubing [they] can be
 receptive to various driveline excitation sources.” Id. col.
 1, ll. 40–42. These excitation sources, in turn, can cause
 the propshaft to vibrate in three modes: bending mode,
 torsion mode, and shell mode. Id. col. 1, ll. 42–44. The ’911
 patent describes these vibration modes as follows:
     Bending mode vibration is a phenomenon wherein
     energy is transmitted longitudinally along the
     shaft and causes the shaft to bend at one or more
     locations. Torsion mode vibration is a phenomenon
     wherein energy is transmitted tangentially
     through the shaft and causes the shaft to twist.
     Shell mode vibration is a phenomenon wherein a
     standing wave is transmitted circumferentially
     about the shaft and causes the cross-section of the
     shaft to deflect or bend along one or more axes.
 Id. col. 1, ll. 44–52. These vibration modes correspond to
 different frequencies. Because such vibrations cause unde-
 sirable noise, “techniques [had, prior to the ’911 patent,]
 been employed to attenuate vibrations in propshafts in-
 cluding the use of weights and liners.” Id. col. 1, ll. 53–54.
     AAM agreed that “[t]he methods for determining natu-
 ral frequencies and damping are well known in the art.”
Case: 18-1763     Document: 134      Page: 4    Filed: 07/31/2020




 4      AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                     LLC


 AAM Op. Br. 8. Some of these are described in the specifi-
 cation. Those techniques include “the use of weights and
 liners.” Id. col. 1, l. 54. Elaborating, the patent first de-
 scribes the use of “plugs or weights” that are inserted to
 frictionally engage a propshaft to damp certain vibrations.
 Id. col. 1, l. 53–col. 2, l. 4. It then describes several prior-
 art dampers and “hollow liners.” See, e.g., id. col. 2, ll. 5–
 37; col. 6, ll. 49–53. The specification describes prior art
 hollow liners as tubes made of a fibrous material (like card-
 board) with outer resilient members that “frictionally en-
 gage the inner diameter of the [propshaft].” Id. col. 6, ll.
 56–65.
       Two types of attenuation are relevant here: resistive
 attenuation and reactive attenuation. “[R]esistive attenu-
 ation of vibration refers to a vibration attenuation means
 that deforms as vibration energy is transmitted through
 it . . . so that the vibration attenuation means absorbs . . .
 the vibration energy.” Id. col. 1, ll. 61–65. A liner that is
 properly tuned to attenuate shell mode vibration through
 resistive attenuation “matches” the shell mode vibration
 (i.e., a particular natural frequency) of the propshaft such
 that it absorbs, through friction damping, the shell mode
 vibration of the propshaft. J.A. 1933, 2000–02. “[R]eactive
 attenuation of vibration refers to a mechanism that can os-
 cillate in opposition to the vibration energy [of the
 propshaft] to thereby ‘cancel out’ a portion of the vibration
 energy.” ’911 patent, col. 2, ll. 15–18. Thus, to design a
 liner to perform reactive attenuation of a bending mode vi-
 bration “the liner frequency must match the propshaft fre-
 quency and involve translation of the liner to effectively
 couple with the propshaft bending mode.” AAM Op. Br. 6
 (citing J.A. 2076–77, 4036–37, 5218).
     According to the ’911 patent’s specification, prior art
 weights, dampers, and hollow liners that were designed to
 individually attenuate each of the three propshaft vibra-
 tion modes—bending, shell, and torsion—already existed.
 ’911 patent, col. 1, l. 53–col. 2, l. 38. But these prior art
Case: 18-1763    Document: 134     Page: 5    Filed: 07/31/2020




 AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS           5
 LLC


 damping methods were assertedly not suitable for attenu-
 ating two vibration modes simultaneously. See id. Thus,
 the patent identified “a need in the art for an improved
 method for damping various types of vibrations in a hollow
 shaft” that “facilitates the damping of shell mode vibration
 as well as the damping of bending mode vibration” simul-
 taneously. Id. col. 2, ll. 39–43. AAM argues that the in-
 vention is the tuning of a liner in order to produce
 frequencies that dampen both the shell mode and bending
 mode vibrations simultaneously. It argues as well on ap-
 peal that the use of liners to dampen bending mode vibra-
 tion is itself inventive.
     The district court treated independent claims 1 and 22
 of the ’911 patent as representative of the asserted claims
 (claims 1–6, 12, 13, 19–24, 26, 27, 31, 34–36). Those two
 claims recite methods of manufacturing:
     1. A method for manufacturing a shaft assembly of
     a driveline system, the driveline system further in-
     cluding a first driveline component and a second
     driveline component, the shaft assembly being
     adapted to transmit torque between the first
     driveline component and the second driveline com-
     ponent, the method comprising:
     providing a hollow shaft member;
     tuning at least one liner to attenuate at least two
     types of vibration transmitted through the shaft
     member; and
     positioning the at least one liner within the shaft
     member such that the at least one liner is config-
     ured to damp shell mode vibrations in the shaft
     member by an amount that is greater than or equal
     to about 2%, and the at least one liner is also con-
     figured to damp bending mode vibrations in the
     shaft member, the at least one liner being tuned to
     within about ±20% of a bending mode natural
Case: 18-1763     Document: 134       Page: 6     Filed: 07/31/2020




 6      AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                     LLC


     frequency of the shaft assembly as installed in the
     driveline system.
                            *    *    *
     22. A method for manufacturing a shaft assembly
     of a driveline system, the driveline system further
     including a first driveline component and a second
     driveline component, the shaft assembly being
     adapted to transmit torque between the first
     driveline component and the second driveline com-
     ponent, the method comprising:
     providing a hollow shaft member;
     tuning a mass and a stiffness of at least one liner,
     and
     inserting the at least one liner into the shaft mem-
     ber;
     wherein the at least one liner is a tuned resistive
     absorber for attenuating shell mode vibrations and
     wherein the at least one liner is a tuned reactive
     absorber for attenuating bending mode vibrations.
 ’911 patent, col. 10, ll. 10–27; id. col. 11, ll. 24–36.
                                II
     AAM sued Neapco on December 18, 2015, alleging in-
 fringement of the ’911 patent. The parties filed cross-mo-
 tions for summary judgment as to patent eligibility under
 § 101. On February 27, 2018, the district court granted
 Neapco’s motion for summary judgment, and denied AAM’s
 cross-motion. Applying the two-step analysis of Mayo Col-
 laborative Services v. Prometheus Laboratories, Inc., 566
 U.S. 66 (2012), and Alice Corp. Pty. Ltd. v. CLS Bank In-
 ternational, 573 U.S. 208 (2014), the court held that the as-
 serted claims of the ’911 patent are invalid because they
 claim ineligible subject matter under § 101.
Case: 18-1763    Document: 134      Page: 7     Filed: 07/31/2020




 AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS             7
 LLC


     The district court construed the claim 1 limitation
 “tuning at least one liner to attenuate at least two types of
 vibration transmitted through the shaft member” to mean
 “controlling characteristics of at least one liner to configure
 the liner to match a relevant frequency or frequencies to
 reduce at least two types of vibration transmitted through
 the shaft member.” J.A. 1046. The district court construed
 the claim 22 limitation “tuning a mass and a stiffness of at
 least one liner” to mean “controlling the mass and stiffness
 of at least one liner to configure the liner to match the rel-
 evant frequency or frequencies.” J.A. 15, 1047. No party
 contests the district court’s construction on appeal.
      At step 1 of the Mayo/Alice analysis, the district court
 concluded that the Asserted Claims, “considered as a
 whole,” are “directed to the mere application of Hooke’s
 law,” treating claims 1 and 22 as representative. J.A. 4–5,
 11. The district court held that the claims’ direction to tune
 a liner to attenuate different vibration modes amounted to
 merely “instruct[ing] one to apply Hooke’s law to achieve
 the desired result of attenuating certain vibration modes
 and frequencies” without “provid[ing] [a] particular means
 of how to craft the liner and propshaft in order to do so.”
 J.A. 17. The district court made no distinction between
 claims 1 and 22 in its analysis. See J.A. 15 n.3.
     Hooke’s law is an equation that describes the relation-
 ship between an object’s mass, its stiffness, and the fre-
 quency at which the object vibrates. Friction damping is a
 natural phenomenon whereby damping “occur[s] due to the
 resistive friction and interaction of two surfaces that press
 against each other as a source of energy dissipation.” J.A.
 1604.
     At step 2 of the Mayo/Alice analysis, the district court
 determined that the claimed “additional steps consist of
 well-understood, routine, conventional activity already en-
 gaged in by the scientific community . . . and those steps,
 when viewed as a whole, add nothing significant beyond
Case: 18-1763    Document: 134     Page: 8    Filed: 07/31/2020




 8     AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                    LLC


 the sum of their parts taken separately.” J.A. 16 (quoting
 Mayo, 566 U.S. at 79–80). The district court concluded that
 the claims were not patent eligible. Id.
     AAM appeals. We have jurisdiction under 28 U.S.C.
 § 1295(a)(1). We review a district court’s grant of summary
 judgment de novo, applying the same test on review that
 the district court applied. Summary judgment is appropri-
 ate where “there is no genuine dispute as to any material
 fact and the movant is entitled to judgment as a matter of
 law.” Fed. R. Civ. P. 56(a). The issue of patent eligibility
 under § 101 is a question of law, reviewed de novo. In re
 BRCA1– and BRCA2– Based Hereditary Cancer Test Pa-
 tent Litig., 774 F.3d 755, 759 (Fed. Cir. 2014). “While pa-
 tent eligibility is ultimately a question of law,” the
 underlying issue of “[w]hether something is well-under-
 stood, routine, and conventional to a skilled artisan at the
 time of the patent is a factual determination.” Berkheimer
 v. HP Inc., 881 F.3d 1360, 1369 (Fed. Cir. 2018), cert. de-
 nied, 140 S.Ct. 911 , 2020 WL 129532 (Jan. 13, 2020).
                         DISCUSSION
     Section 101 provides that “any new and useful process,
 machine, manufacture, or composition of matter, or any
 new and useful improvement thereof” may be eligible to ob-
 tain a patent. 35 U.S.C. § 101. But the Supreme Court has
 long recognized that § 101 “contains an important implicit
 exception: Laws of nature, natural phenomena, and ab-
 stract ideas are not patentable.” Ass’n for Molecular Pa-
 thology v. Myriad Genetics, Inc., 569 U.S. 576, 589 (2013)
 (brackets omitted) (quoting Mayo, 566 U.S. at 70). The Su-
 preme Court has stated that “without this exception, there
 would be considerable danger that the grant of patents
 would ‘tie up’ the use of such tools and thereby ‘inhibit fu-
 ture innovation premised upon them.’” Id. (quoting Mayo,
 566 U.S. at 73).
     Our analysis of § 101 follows the Supreme Court’s two-
 step test established in Mayo and Alice. At step one of the
Case: 18-1763    Document: 134     Page: 9    Filed: 07/31/2020




 AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS           9
 LLC


 Mayo/Alice test, we ask whether the claims are directed to
 a law of nature, natural phenomenon, or abstract idea. Al-
 ice, 573 U.S. at 217 (citing Mayo, 566 U.S. at 77). If the
 claims are so directed, we then ask whether the claims em-
 body some “inventive concept”—i.e., whether the claims
 contain “an element or combination of elements that is ‘suf-
 ficient to ensure that the patent in practice amounts to sig-
 nificantly more than a patent upon the ineligible concept
 itself.’” Id. at 217–18 (brackets omitted) (quoting Mayo,
 566 U.S. at 72–73).
     We conclude that independent claim 22 of the ’911 pa-
 tent is patent ineligible under section 101 because it simply
 requires the application of Hooke’s law to tune a propshaft
 liner to dampen certain vibrations. Independent claim 36
 and asserted claims that depend from claim 22 are also in-
 eligible. Because claim 1 also requires “positioning” in ad-
 dition to tuning and may reflect a broader definition of
 tuning, we remand to the district court to address the eli-
 gibility of claim 1 and its dependent claims in the first in-
 stance.
                         I. CLAIM 22
     We first address claim 22.
                              A
     To determine what a claim is “directed to” at step one,
 we look to the “focus of the claimed advance.” See, e.g.,
 Trading Techs Int’l, Inc. v. IBG LLC, 921 F.3d 1378, 1384
 (Fed. Cir. 2019). 2 A claim to a method of manufacturing



     2  Accord Intellectual Ventures I LLC v. Capital One
 Fin. Corp., 850 F.3d 1332, 1338 (Fed. Cir. 2017); Intellec-
 tual Ventures I LLC v. Erie Indemnity Co., 850 F.3d 1315,
 1325 (Fed. Cir. 2017); Affinity Labs of Tex., LLC v.
 DIRECTV, LLC, 838 F.3d 1253, 1257–58 (Fed. Cir. 2016);
Case: 18-1763    Document: 134      Page: 10     Filed: 07/31/2020




  10    AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                     LLC


  can be directed to a natural law. 3 The ’911 patent claims a
  method of manufacturing a driveline propshaft containing
  a liner designed such that its frequencies attenuate two
  modes of vibration simultaneously and (according to the
  patentee on appeal) a manufacturing method to tuning lin-
  ers to attenuate bending mode vibration. At step 1, the
  question is whether the claimed methods are directed to
  laws of nature.
       The Supreme Court’s cases focus on the claims, not the
  specification, to determine section 101 eligibility. As the
  Supreme Court said in Mayo: “We must determine whether
  the claimed processes have transformed these unpatenta-
  ble natural laws into patent-eligible applications of those
  laws.” Mayo, 566 U.S. at 72 (emphasis added); see also Al-
  ice, 573 U.S. at 221 (“[W]e must examine the elements of
  the claim to determine whether it contains an ‘inventive



  Enfish, LLC v. Microsoft Corp., 822 F.3d 1327, 1335 (Fed.
  Cir. 2016); Genetic Techs. Ltd. v. Merial LLC, 818 F.3d
  1369, 1375–76 (Fed. Cir. 2016).
      3    See Alice Corp. v. CLS Bank Int’l, 573 U.S. 208, 224
  (2014) (“The fact that a computer ‘necessarily exist[s] in the
  physical, rather than purely conceptual, realm,’ is beside
  the point. There is no dispute that a computer is a tangible
  system (in § 101 terms, a ‘machine’) . . . .”); O’Reilly v.
  Morse, 56 U.S. (15 How.) 62, 113 (1853) (“Neither could the
  man who first discovered that steam might, by a proper ar-
  rangement of machinery, be used as a motive power to
  grind corn or spin cotton, claim the right to the exclusive
  use of steam as a motive power for the purpose of producing
  such effects.”); ChargePoint, Inc. v. SemaConnect, Inc., 920
  F.3d 759, 770 (Fed. Cir. 2019), cert. denied, 140 S. Ct. 983
  (2020) (“[A]s the Supreme Court indicated in Alice,
  whether a device is ‘a tangible system (in § 101 terms, a
  “machine”)’ is not dispositive.” (quoting Alice, 573 U.S. at
  224)).
Case: 18-1763     Document: 134      Page: 11     Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS             11
  LLC


  concept.’” (emphasis added) (internal quotation marks
  omitted)).
      Similarly, we have repeatedly held that features that
  are not claimed are irrelevant as to step 1 or step 2 of the
  Mayo/Alice analysis. See, e.g., ChargePoint, 920 F.3d at
  769 (“[A]ny reliance on the specification in the § 101 anal-
  ysis must always yield to the claim language. . . . [T]he
  specification cannot be used to import details from the
  specification if those details are not claimed.”); Synopsys,
  Inc. v. Mentor Graphics Corp., 839 F.3d 1138, 1149 (Fed.
  Cir. 2016) (“The § 101 inquiry must focus on the language
  of the Asserted Claims themselves.”); Ariosa Diagnostics,
  Inc. v. Sequenom, Inc., 788 F.3d 1371, 1379 (Fed. Cir. 2015)
  (rejecting an alleged inventive concept because it was “not
  the invention claimed by the . . . patent” (emphasis added));
  Accenture Glob. Servs., GmbH v. Guidewire Software, Inc.,
  728 F.3d 1336, 1345 (Fed. Cir. 2013) (“[Where t]he limita-
  tions of the . . . claims . . . do not provide sufficient addi-
  tional features or limit the abstract concept in a
  meaningful way[,] . . . the level of detail in the specification
  does not transform a claim reciting only an abstract con-
  cept into a patent-eligible system or method.”); see also Ari-
  osa Diagnostics, Inc. v. Sequenom, Inc., 809 F.3d 1282,
  1286 (Fed. Cir. 2015) (Lourie, J., concurring) (noting that
  the appropriate focus is “on the claims we have rather than
  those we might have had” (emphasis added)).
       In contrast to a number of other natural law cases, the
  patentee here does not even claim to have discovered a pre-
  viously unknown natural law. Instead, it defines a goal
  (“tuning a liner” to achieve certain types of vibration atten-
  uation). Claim 22 explicitly provides for “tuning a mass
  and a stiffness of at least one liner.” ’911 patent, col. 11,
  l. 31. Under the district court’s construction, “tuning a
  mass and a stiffness of at least one liner” in claim 22 means
  “controlling the mass and stiffness of at least one liner to
  configure the liner to match the relevant frequency or fre-
  quencies.” J.A. 15, 1047. Thus, claim 22 requires use of a
Case: 18-1763     Document: 134     Page: 12     Filed: 07/31/2020




  12     AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                      LLC


  natural law of relating frequency to mass and stiffness—
  i.e., Hooke’s law. Claim 22 confers patent coverage if the
  attenuation goal is achieved by one skilled in the art using
  any method, including any method implemented by com-
  puter modeling and trial and error. That claim 22 here
  merely describes a desired result is evident from the face
  of the claim. The claim on its face does not identify the
  “particular [tuned] liners” or the “improved method” of tun-
  ing the liners to achieve the claimed result. AAM Op. Br.
  27; ’911 patent, col. 2, ll. 39–43. No factual finding was or
  is required.
      In arguing that patent claim 22 does not merely claim
  a result and so is not directed to whatever natural laws
  make the result possible, AAM does not dispute that
  Hooke’s law mathematically relates the mass and/or stiff-
  ness of an object to the frequency with which that object
  oscillates (vibrates). In fact, both parties’ witnesses agree
  that Hooke’s law undergirds the design of a liner so that it
  exhibits a desired damping frequency pursuant to the
  claimed invention. For example, Neapco’s expert, Dr.
  Becker, stated that “the phrase ‘tuning a mass and a stiff-
  ness of at least one liner’ claims Hooke’s law.” J.A. 1604.
  Dr. Sun, one of the named inventors of the ’911 patent,
  stated in his deposition:
       Q. But to change the frequency of any damper, it
       comes down to basic physics, doesn’t it; changing
       the mass or the stiffness of that damper that will
       adjust the frequency?
       A. You change a tuned liner, yeah, by adjusting the
       controlling variables and to get to the tuning that
       is needed.
       Q. And one of those variables is stiffness, correct?
       A. Correct.
       Q. And one of them is the mass, correct?
Case: 18-1763     Document: 134      Page: 13    Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS            13
  LLC


      A. Yes.
  J.A. 1757 (92:15–25). AAM’s engineering manager like-
  wise admitted that “if [one] do[es] something to control the
  stiffness [or mass]” of a liner—the variables directly impli-
  cated by Hooke’s law—that person is “directly controlling
  tuning.” J.A. 2547 (20:23–21:1).
       Rather, AAM asserts that tuning a liner such that it
  attenuates two different vibration modes (or just dampens
  bending mode vibrations) is complicated in practice, involv-
  ing more than simple application of Hooke’s law. AAM Op.
  Br. 19 (“Complicated objects—such as propshaft liners—
  cannot be simplified to a single degree-of-freedom mass-
  spring damper such that their behavior is governed simply
  by Hooke’s law.”); see also id. at 39–41, 43. AAM insists
  that the process of tuning a liner according to natural laws
  may involve extensive computer modelling, including finite
  element analysis (“FEA”), and experimental modal analy-
  sis (that is, trial and error). 4 And while recognizing that
  “methods for determining natural frequencies and damp-
  ing are well known in the art,” including use of “FEA mod-
  els” and “testing for natural frequencies and damping of
  propshafts by performing experimental modal analysis,”
  AAM Op. Br. 8–11, 20–21, AAM contends that it invented
  an improved method of tuning. 5



      4   “Experimental modal analysis involves [physically]
  exciting the propshaft and/or liner using an actuator,
  measuring the response using a sensor, and calculating the
  natural frequencies and damping ratios using a computer
  algorithm.” J.A. 5207.
      5   While the patent makes no references to computer
  modeling and trial and error, AAM pointed to computer
  modeling in its briefing in the district court, see note 4, su-
  pra, and it has done the same in its briefs in this court. See,
Case: 18-1763     Document: 134      Page: 14     Filed: 07/31/2020




  14     AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                      LLC


       But neither established processes nor “improved” pro-
  cesses for implementing the underlying natural laws are
  claimed. While AAM may have discovered patentable re-
  finements of the prior art process, such as particular uses
  of “sophisticated FEA [finite element analysis] models dur-
  ing its design process,” id. at 45, neither the specifics of any
  novel computer modelling, nor the specifics of any experi-
  mental modal analysis are included as limitations in claim
  22. 6 These unclaimed features cannot function to remove
  claim 22 from the realm of ineligible subject matter. See
  ChargePoint, 920 F.3d at 766.
      To be clear, we do not suggest that such specific novel
  computer or experimental processes could not be claimed.
  This case would be significantly different, if, for example,
  specific FEA models were included in claim 22. But they



  e.g., AAM Op. Br. 20 (“American Axle uses ‘very sophisti-
  cated FEA models.’” (quoting Dr. Sun, one of the named in-
  ventors of the ’911 patent)) id. at 45 (“American
  Axle . . . uses sophisticated FEA models during its design
  process . . . .”); Reply Br. 12 (“Dr. Sun’s cited testi-
  mony . . . concerned the use of FEA analysis . . . to simplify
  otherwise complex liners to model and predict their perfor-
  mance.”).
       6   The specification describes tuning in terms of the
  result achieved, rather than the particular process by
  which the result is accomplished. For instance, the speci-
  fication states that “a liner 204 will be considered to be
  tuned to a relevant frequency if it is effective in attenuating
  vibration at the relevant frequency.” ’911 patent, col. 8, ll.
  28–31. Later in the same column, the patent gives an ex-
  ample of a “liner [that is] considered to be tuned to a rele-
  vant shell mode frequency if it damps shell mode vibrations
  by an amount that is greater than or equal to about 2%.”
  Id. at col. 8, ll. 44–47. The specification’s concept of tuning
  is merely results-based.
Case: 18-1763     Document: 134      Page: 15     Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS             15
  LLC


  are not. What is missing is any physical structure or steps
  for achieving the claimed result. The focus of the claimed
  advance here is simply the concept of achieving that result,
  by whatever structures or steps happen to work.
      The breadth of claim 22 is illustrated by the testimony
  of AAM’s expert “that tuning involves controlling the char-
  acteristics (e.g., mass and stiffness) of the liner through, for
  example, its design, manufacturing, and installation to re-
  duce vibration at a relevant frequency,” J.A. 169, and by
  AAM’s admission during the claim construction hearing,
  where AAM argued one could infringe claim 22 of the ’911
  patent by whatever means will achieve the result “[e]ven if
  you didn’t try to [tune] and didn’t know you did it.” J.A.
  699. Thus, the problem is that claim 22’s instruction to
  tune a liner essentially amounts to simply claiming a re-
  sult.
                                 B
      Claiming a result that involves application of a natural
  law without limiting the claim to particular methods of
  achieving the result runs headlong into the very problem
  repeatedly identified by the Supreme Court in its cases
  shaping eligibility analysis. See Mayo, 566 U.S. at 71–73;
  Parker v. Flook, 437 U.S. 584, 590–95 (1978); Mackay Ra-
  dio & Telegraph Co. v. Radio Corp. of Am., 306 U.S. 86, 94–
  101 (1939); O’Reilly v. Morse, 56 U.S. (15 How.) 62, 112–17
  (1853). The Supreme Court has long held that claims that
  state a goal without a solution are patent ineligible. As
  early as Le Roy v. Tatham, 55 U.S. (14 How.) 156 (1852),
  the Court held that claiming a concept without the partic-
  ular steps of carrying it out “would prohibit all other per-
  sons from making the same thing by any means
  whatsoever,” and that such claims are ineligible for patent-
  ability. Id. at 174–75; Corning v. Burden, 56 U.S. 252, 268
  (1853) (“It is for the discovery or invention of some practi-
  cable method or means of producing a beneficial result or
  effect, that a patent is granted, and not for the result or
Case: 18-1763     Document: 134     Page: 16     Filed: 07/31/2020




  16       AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                        LLC


  effect itself.”), quoted by Diamond v. Diehr, 450 U.S. 175,
  182 n.7 (1981).
       Our cases as well have consistently rejected such
  claims as unpatentable. As “reflected repeatedly in our
  cases,” to avoid ineligibility, a claim must “ha[ve] the spec-
  ificity required to transform [the] claim from one claiming
  only a result to one claiming a way of achieving it.” SAP
  Am., Inc. v. InvestPic, LLC, 898 F.3d 1161, 1167 (Fed. Cir.
  2018) (collecting cases). 7 Similarly, in Interval Licensing



       7   Affinity Labs of Texas, LLC v. DIRECTV, LLC, 838
  F.3d 1253, 1258 (Fed. Cir. 2016) (claim is an ineligible ab-
  stract idea because “[t]here is nothing in the claim that is
  directed to how to implement out-of-region broadcasting on
  a cellular telephone”); Apple, Inc. v. Ameranth, Inc., 842
  F.3d 1229, 1241 (Fed. Cir. 2016) (claims found ineligible
  and “directed to an abstract idea” because they “d[id] not
  claim a particular way of programming or designing the
  software to create menus . . . , but instead merely claim[ed]
  the resulting systems”); Internet Patents Corp. v. Active
  Network, Inc., 790 F.3d 1343, 1348 (Fed. Cir. 2015) (finding
  claim abstract because it “contain[ed] no restriction on how
  the result is accomplished”); Secured Mail Sols. LLC v.
  Universal Wilde, Inc., 873 F.3d 905, 911 (Fed. Cir. 2017)
  (finding claims abstract because they were “not limited by
  rules or steps that establish[ed] how the focus of the meth-
  ods [wa]s achieved”); ChargePoint, 920 F.3d at 770 (finding
  claims directed to abstract idea where broad claim lan-
  guage “would cover any mechanism for implementing net-
  work communication on a charging station” rather than a
  specific way of doing so); Interval Licensing LLC v. AOL,
  Inc., 896 F.3d 1335, 1345–46 (Fed. Cir. 2018) (claims ineli-
  gible “because they consist[ed] of generic and conventional
  information acquisition and organization steps that are
  connected to, but do not convert, the abstract idea . . . into
Case: 18-1763     Document: 134      Page: 17     Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS             17
  LLC


  LLC v. AOL, Inc., 896 F.3d 1335 (Fed. Cir. 2018), we reit-
  erated the importance of this distinction in describing prior
  Supreme Court cases in which inventors “lost . . . claim[s]
  that encompassed all solutions for achieving a desired re-
  sult” because the “claims failed to recite a practical way of
  applying an underlying idea . . . [and] instead were drafted
  in such a result-oriented way that they amounted to en-
  compassing ‘the principle in the abstract’ no matter how
  implemented.” Id. at 1343; see also Electric Power Grp.,



  a particular conception of how to carry out that concept”
  (emphasis added)); Innovation Sci., LLC v. Amazon.com,
  Inc., 778 F. App’x 859, 863 (Fed. Cir. 2019) (finding ineligi-
  ble a claim reciting coverage “in merely functional, result-
  oriented terms”); Univ. of Fla. Research Found., Inc. v. Gen.
  Elec. Co., 916 F.3d 1363, 1364, 1368 (Fed. Cir. 2019) (find-
  ing claims to be “directed to an abstract idea” where “[n]ei-
  ther the . . . patent, nor its claims, explain[ed] how the
  drivers do the conversion that [Appellant] points to.”); Two-
  Way Media Ltd. v. Comcast Cable Commc’ns, LLC, 874
  F.3d 1329, 1337 (Fed. Cir. 2017) (claim ineligible abstract
  idea where “[t]he claim require[d] the functional results of
  ‘converting,’ ‘routing,’ ‘controlling,’ ‘monitoring,’ and ‘accu-
  mulating records,’ but d[id] not sufficiently describe how to
  achieve these results in a non-abstract way”); see also Fin-
  jan, Inc. v. Blue Coat Sys., Inc., 879 F.3d 1299, 1305 (Fed.
  Cir. 2018) (“Apple, Affinity Labs, and other similar cases
  hearken back to a foundational patent law principle: that
  a result, even an innovative result, is not itself patenta-
  ble.”); McRO, Inc. v. Bandai Namco Games Am. Inc., 837
  F.3d 1299, 1314 (Fed. Cir. 2016) (“[In section 101 analysis
  w]e . . . look to whether the claims . . . focus on a specific
  means or method that improves the relevant technology or
  are instead directed to a result or effect that itself is the
  abstract idea and merely invoke generic processes and ma-
  chinery.”).
Case: 18-1763    Document: 134      Page: 18     Filed: 07/31/2020




  18    AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                     LLC


  LLC v. Alstom S.A., 830 F.3d 1350, 1355–56 (Fed. Cir.
  2016) (noting that “the essentially result-focused, func-
  tional character of claim language has been a frequent fea-
  ture of claims held ineligible under § 101”).
      While many of these cases involved the abstract idea
  category, the same principle necessarily applies in natural
  law cases. In Mayo, the Court concluded that “to transform
  an unpatentable law of nature into a patent-eligible appli-
  cation of such a law, one must do more than simply state
  the law of nature while adding the words ‘apply it.’” 566
  U.S. at 72; see also id. at 82 (“[S]imply appending conven-
  tional steps, specified at a high level of generality, to laws
  of nature, natural phenomena, and abstract ideas cannot
  make those laws, phenomena, and ideas patentable.” (em-
  phasis added)). Similarly, in Diamond v. Diehr, 450 U.S.
  175 (1981), the Court recognized “that when a claim recites
  a mathematical formula (or scientific principle or phenom-
  enon of nature), an inquiry must be made into whether the
  claim is seeking patent protection for that formula in the
  abstract.” Id. at 191 (emphasis added).
      The Supreme Court’s decisions in Le Roy and O’Reilly
  may be viewed as applying this principle in the natural law
  context. For example, in O’Reilly v. Morse, 56 U.S. (15
  How.) 62 (1853), the Supreme Court held claim for “use of
  the motive power of the electric or galvanic current . . . for
  marking or printing intelligible characters . . . at any dis-
  tances” ineligible because “it matter[ed] not by what pro-
  cess or machinery the result [wa]s [to be] accomplished.”
  Id. at 113–20. Both claim 8 in O’Reilly and claim 22 here
  recite a natural law (electromagnetism in O’Reilly and
  Hooke’s law here) and a result to be achieved (printing
  characters at a distance in O’Reilly and producing a liner
  to dampen specific vibrations). And just as claim 8 in
  O’Reilly did not recite any engineering or techniques to
  achieve this result, claim 22 likewise provides no details.
  Thus, claim 22, like claim 8 in O’Reilly, is directed to a
Case: 18-1763      Document: 134      Page: 19      Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS               19
  LLC


  natural law because it clearly invokes a natural law, and
  nothing more, to accomplish a desired result.
      More recently, the Supreme Court’s decision in Parker
  v. Flook, 437 U.S. 584 (1978), also exemplified this princi-
  ple. In Flook, the Supreme Court considered the patent el-
  igibility of a method for updating alarm limits during
  catalytic conversion processes. 437 U.S. at 585. The
  method involved an initial step of measuring temperature,
  a second step of using a formula to calculate an updated
  alarm-limit value, and a final step in which the alarm limit
  is adjusted to the updated value. Id.; see also id. at 596–98
  (quoting and describing claim). What was missing from the
  claimed method reflected what was missing from the pa-
  tent application as a whole, which “d[id] not purport to ex-
  plain how to select . . . any of the . . . variables” involved, or
  “purport to contain any disclosure relating to the chemical
  process at work, the monitoring of process variables, or the
  means of setting off an alarm or adjusting an alarm sys-
  tem.” Id. at 586.
       The Court in Flook held that the claimed method con-
  tained no patent-eligible invention. Id. at 594. Though the
  Court recognized that the use of a mathematical formula
  or law of nature did not alone make a claim patent ineligi-
  ble, it explained that what was required was “an inventive
  application of the principle.” Id. at 593–94. Such an in-
  ventive application, the Court concluded, was not present
  in the claimed method. Id. at 594.
       Diehr, on the other hand, involved a situation in which
  a patent application claimed a new and specific process of
  molding rubber products “which incorporate[d] in it a more
  efficient solution of the [Arrhenius] equation” (a natural
  law). 450 U.S. at 188. Though the Supreme Court in Diehr
  explained that a mathematical formula itself was not pa-
  tent eligible subject matter, it concluded that the alleged
  invention claimed in that case was patent eligible. The in-
  vention involved a new rubber-curing process with a
Case: 18-1763     Document: 134     Page: 20    Filed: 07/31/2020




  20       AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                        LLC


  specific and detailed series of steps (one of which included
  the use of a natural law) that limited the possibility of
  preempting the natural law itself. Id. at 187–88, 191–92.
  In Diehr, unlike this case, “[t]hese other steps apparently
  added to the formula something that in terms of patent
  law’s objectives had significance—they transformed the
  process into an inventive application of the for-
  mula.” Mayo, 566 U.S. at 81 (discussing Diehr, 450 U.S. at
  187). Nevertheless, the Court reaffirmed Flook’s teaching
  that “[a] mathematical formula does not suddenly become
  patentable subject matter simply by having the applicant
  acquiesce to limiting the reach of the patent for the formula
  to a particular technological use” nor through the addition
  of “token postsolution activity.” Diehr, 450 U.S. at 191–92
  & n.14. 8
      Like the claims in Flook, claim 22 of the ’911 patent is
  directed to the use of a natural law: Hooke’s law. As in
  Flook, where the claimed method did not specify how vari-
  ables were measured or how the alarm system functioned,
  claim 22 here does not specify how target frequencies are



       8   See also Genetic Techs. Ltd. v. Merial L.L.C., 818
  F.3d 1369, 1375 (Fed. Cir. 2016) (finding claim to be di-
  rected to ineligible law of nature because it “cover[ed] es-
  sentially all applications, via standard experimental
  techniques, of the law of linkage disequilibrium to the prob-
  lem of detecting coding sequences of DNA”); Athena Diag-
  nostics, Inc. v. Mayo Collaborative Servs., LLC, 927 F.3d
  1333, 1359 (Fed. Cir. 2019) (Moore, J., dissenting) (order
  denying petition for en banc rehearing) (“[T]he Supreme
  Court suggests we should consider the level of specificity in
  the claims to determine whether the claim is even directed
  to the natural law.”); id. at 1362 (“The concreteness and
  specificity of the claims in Athena move them from reciting
  a law of nature to a particular application of a law of na-
  ture.”).
Case: 18-1763    Document: 134      Page: 21    Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS          21
  LLC


  determined or how, using that information, liners are
  tuned to attenuate two different vibration modes simulta-
  neously, or how such liners are tuned to dampen bending
  mode vibrations. Claim 22 here simply instructs the
  reader to tune the liner to achieve a claimed result, without
  limitation to particular ways to do so. This holding as to
  step 1 of Alice extends only where, as here, a claim on its
  face clearly invokes a natural law, and nothing more, to
  achieve a claimed result.
                               C
      As to Mayo/Alice step 2, nothing in claim 22 qualifies
  as an “inventive concept” to transform it into patent eligi-
  ble matter. AAM contends that claim 22 includes numer-
  ous inventive concepts that were neither previously known,
  nor conventional or routine. AAM’s arguments in this re-
  spect essentially amount to an assertion that prior to the
  ’911 patent, liners had never been tuned to damp propshaft
  vibrations or, at least, had not been used to damp two dif-
  ferent vibration modes simultaneously (or perhaps just to
  damp bending mode vibrations). 9 This amounts to no more
  than a restatement of the assertion that the desired results
  are an advance. We have already explained that, insofar
  as claim 22 here merely claims the achievement of results,
  they are directed to ineligible matter. As we held in BSG
  Tech LLC v. Buyseasons, Inc., 899 F.3d 1281 (Fed. Cir.
  2018), “a claimed invention’s use of the ineligible concept


      9   To the extent that AAM’s opening summary judg-
  ment brief as to § 101 patent eligibility can be understood
  to argue that there are disputed issues of material fact as
  to whether the patent discloses an inventive concept, it re-
  lies only on Dr. Rahn’s testimony that dual-damping of
  bending mode and shell mode vibrations was new and un-
  conventional. AAM Mot. for Summ. J. 8–9, American Axle
  & Manuf., Inc. v. Neapco Hldgs. LLC, No. 15-01168 (D. Del.
  Aug. 11, 2017), ECF No. 160.
Case: 18-1763       Document: 134    Page: 22     Filed: 07/31/2020




  22        AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                         LLC


  to which it is directed cannot supply the inventive concept”
  required to cross the line into eligibility. Id. at 1290; see
  also Trading Techs., 921 F.3d at 1385 (“The abstract idea
  itself cannot supply the inventive concept, ‘no matter how
  groundbreaking the advance.’” (quoting SAP, 898 F.3d at
  1170)); ChargePoint, 920 F.3d at 775 (“[T]he abstract idea
  itself . . . cannot supply the inventive concept at step two.”).
      Claim 22 discloses no other inventive concept. The real
  inventive work lies in figuring out how to design a liner to
  damp two different vibration modes simultaneously, and
  no such inventive work is recited in claim 22. The remain-
  ing steps of claim 22, like the steps involved in the Flook
  patent, amount to no more than conventional pre- and post-
  solution activity. There is no other inventive concept at
  step two in the claims and no dispute of any material fact.
      Claim 22 is not patent eligible. Claim 36 10 is virtually
  indistinguishable from claim 22 and was not argued




       10    Claim 36 recites:
       A method for manufacturing a shaft assembly of a
       driveline system, the driveline system further in-
       cluding a first driveline component and a second
       driveline component, the shaft assembly being
       adapted to transmit torque between the first
       driveline component and the second driveline com-
       ponent, the method comprising:
       providing a hollow shaft member;
       tuning a mass and a stiffness of at least one liner;
       and
       inserting the at least one liner into the shaft mem-
       ber;
Case: 18-1763    Document: 134      Page: 23     Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS             23
  LLC


  separately on appeal or in district court. It is thus likewise
  not patent eligible.
            II. CLAIMS DEPENDING FROM CLAIM 22
       Having determined that independent claim 22 is not
  patent eligible under § 101, we need not separately deter-
  mine eligibility of the asserted dependent claims. The dis-
  trict court found independent claim 22 collectively
  representative of all claims dependent from this claim.
  AAM did not argue before the district court that the de-
  pendent claims change the outcome of the eligibility anal-
  ysis. Nor did AAM make such an argument in its opening
  brief on appeal. 11 Although at oral argument AAM disa-
  greed that 22 is representative of the others and stated that
  it never acceded to such a finding, Oral Arg. 30:07–40, it
  was unable to identify any part of its opening brief that
  presented such an argument and admitted that it was “not
  suggesting that the other claims should come out differ-
  ently,” id. at 30:40–31:16. We therefore find any such



      wherein a ratio of a mass of the at least one liner to
      a mass of the shaft member is about 5% to about
      30%;
      wherein the at least one liner is a tuned resistive
      absorber for attenuating shell mode vibrations; and
      wherein the at least one liner is a tuned reactive
      absorber for attenuating at least one of bending
      mode vibrations and torsion mode vibrations.
      11  While AAM’s Reply Brief for the first time argued
  that specific limitations of dependent claims may render
  these claims independently eligible, see Reply Br. 27, those
  arguments were not properly preserved. SmithKline Bee-
  cham Corp. v. Apotex Corp., 439 F.3d 1312, 1319 (Fed. Cir.
  2006) (“Our law is well established that arguments not raised
  in the opening brief are waived.”).
Case: 18-1763      Document: 134    Page: 24    Filed: 07/31/2020




  24        AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                         LLC


  argument waived. See Affinity Labs, 838 F.3d at 1256 n.1
  (treating certain claims as representative where no mean-
  ingful argument made that other claims are materially dif-
  ferent); Electric Power, 830 F.3d at 1352. We note that in
  the rehearing petition concerning the earlier panel deci-
  sion, AAM did not argue that the decision with respect to
  the dependent claims was erroneous, other than to say in a
  footnote that “AAM did not waive any arguments about
  these [dependent] claims.” Petition 14 n.3.
                           III: CLAIM 1
      Claim 1 is different from claim 22. While it is true that
  both claims require “tuning,” claim 1 is more general. It
  requires “tuning at least one liner to attenuate at least two
  types of vibration transmitted through the shaft member.”
  ’911 patent, col. 10, ll. 19–28. The district court construed
  this term to mean “controlling characteristics of at least
  one liner to configure the liner to match a relevant fre-
  quency or frequencies to reduce at least two types of vibra-
  tion transmitted through the shaft member.” J.A. 1046
  (emphasis added). The specification indicates or may sug-
  gest that the “characteristics” that can be “tuned” in claim
  1 include variables other than mass and stiffness. 12 In



       12 The specification recites a nonexclusive list of var-
  iables that can be altered to change the frequencies exhib-
  ited by a liner and a solitary example of a tuned liner
  (though not the process by which that liner was tuned).
  These variables include:
       mass, length and outer diameter of the liner 204,
       diameter and wall thickness of the structural por-
       tion 300, material of which the structural portion
       300 was fabricated, the quantity of resilient mem-
       bers 302, the material of which the resilient mem-
       bers 302 was fabricated, the helix angle 330 and
Case: 18-1763      Document: 134        Page: 25   Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS            25
  LLC


  addition, claim 1, unlike claim 22 has an additional limita-
  tion of “positioning the at least one liner.” 13 ’911 patent,
  col. 10, ll. 19–28.
       In light of the district court’s construction of claim 1,
  which requires only controlling characteristics and posi-
  tioning the liner, we cannot conclude that it is merely di-
  rected to Hooke’s law. In contrast with claim 22, which as
  construed recites nothing more than a desired result and
  an instruction to apply Hooke’s law, we cannot say claim 1
  as construed is directed to a particular natural law and
  nothing more. The mere fact that any embodiment prac-
  ticing claim 1 necessarily involves usage of one or more nat-
  ural laws is by itself insufficient to conclude the claim is
  directed to such natural laws. The district court’s opinion
  suggests that the broader concept of tuning is an abstract
  idea, J.A. 16–17, and the same question may be raised
  about the broad concept of positioning. On appeal, Neapco
  relied on both the natural law and abstract idea categories
  of ineligibility in defending the district court’s decision.
  See, e.g., Neapco Resp. Br. 21, 24. But the abstract idea
  basis was not adequately presented and litigated in the



      pitch 332 with which the resilient member 302 are
      fixed to the structural portion 300, the configura-
      tion of the lip member(s) 322 of the resilient mem-
      ber 302, and the location of the liners 204 within
      the shaft member 200.
  ’911 patent, col. 7, l. 60–col. 8, l. 2.
      13  The claim 22 limitation of “inserting the at least
  one liner into the shaft member” is not equivalent to claim
  1’s “positioning” limitation, and AAM never argued other-
  wise in the district court or on appeal. As discussed supra
  in Section II, any argument that dependent claims 34 and
  35 have a “location limitation,” see Dissent Op. 27–28, have
  been waived by AAM.
Case: 18-1763     Document: 134     Page: 26    Filed: 07/31/2020




  26     AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                      LLC


  district court. We think that it is appropriate to vacate the
  judgment as to claim 1 and its dependent claims and re-
  mand the case for the district court to address this alterna-
  tive eligibility theory in the first instance.
                               IV
       Some brief response to the dissent is required.
      First, contrary to the dissent, we are not “depart[ing]
  from existing § 101 precedent,” Dissent Op. 9, but rather
  faithfully following it in the narrow circumstances of this
  case.
      Second, the dissent argues that “[o]ne important differ-
  ence between this natural law case and every other one
  ever decided is that these claims do not actually recite any
  particular natural law.” Dissent Op. 7. One problem with
  this argument is its characterization of this case as not in-
  volving a recitation of the natural law. Claim 22 expressly
  requires varying frequency attenuation (tuning) based on
  mass and stiffness, as the dissent recognizes (Dissent Op.
  26 (under claim 22, “the liner is tuned to a given frequency
  by adjusting its mass and stiffness”)). As is undisputed,
  what Hooke’s law does is precisely to relate frequency to
  mass and stiffness. See supra at 7. In all but name, there-
  fore, claim 22 recites Hooke’s law. To be clear, however,
  our holding should not be read as an invitation to raise a
  validity challenge against any patent claim that requires
  the application of an unstated natural law; our ruling as to
  claim 1 should make that clear enough. Rather, our hold-
  ing is limited to the situation where a patent claim on its
  face and as construed clearly invokes a natural law, and
  nothing else, to accomplish a desired result.
      There is, moreover, a more fundamental problem with
  the dissent’s argument about claim recitation of a natural
  law. It is true that in Mayo and many other cases the nat-
  ural law itself was stated in the claim. See, e.g., Mayo, 566
  U.S. at 74–75. But the longstanding rejection of eligibility
Case: 18-1763    Document: 134      Page: 27    Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS          27
  LLC


  for a claim to a “result” or “effect,” see Diehr, 450 U.S. at
  182 n.7; Corning, 56 U.S. at 268; Le Roy, 55 U.S. at 175, is
  not limited to claims that also state the natural law that
  produces the result or effect. Moreover, nothing in Mayo
  or any other case suggests that the natural law exception
  requires an express claim recitation of a natural law: the
  analysis is a substantive one about whether the claim is
  “directed to” ineligible matter and, if so, whether there is
  enough other than the ineligible matter itself to create eli-
  gibility. See Alice, 573 U.S. at 217–18; Mayo, 566 U.S. at
  72–73, 77. If patentees could avoid the natural law excep-
  tion by failing to recite the law itself, patent eligibility
  would depend upon the “draftsman’s art,” the very ap-
  proach that Mayo rejected. Id. at 72. Significantly, both
  Mayo and O’Reilly rely on a foundational English case,
  Neilson v. Harford, Webster’s Patent Cases 295, 371
  (1841), which involved this very situation, where the pa-
  tent did not recite the natural law, because the inventor
  was “not aware of the nature and principle of his discov-
  ery.” Id. at 344. “[T]he principle,” “regarded as well
  known,” “that hot air would promote the ignition of fuel
  better than cold,” was not in the patent but was “embodied
  in th[e described] machine.” O’Reilly, 56 U.S. at 116; see
  also Mayo, 566 U.S. at 82–84. The patent was held eligible
  only because it “explained how the principle could be im-
  plemented in an inventive way.” Mayo, 566 U.S. at 83.
      Third, the dissent criticizes our analysis as improperly
  merging enablement and eligibility, arguing that the fail-
  ure of the claims to designate how to achieve the desired
  result is exclusively an issue of enablement. Dissent Op.
  23–26. But we think the criticism rests on a failure to dis-
  tinguish two different “how” requirements in patent law.
  The first such requirement, that of eligibility, is that the
  claim itself (whether by its own words or by statutory in-
  corporation of specification details under section 112(f))
  must go beyond stating a functional result; it must identify
  “how” that functional result is achieved by limiting the
Case: 18-1763      Document: 134      Page: 28     Filed: 07/31/2020




  28        AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                         LLC


  claim scope to structures specified at some level of con-
  creteness, in the case of a product claim, or to concrete ac-
  tion, in the case of a method claim. The Supreme Court
  has so required dating back at least to the Court’s rejection
  of Morse’s claim 8 in O’Reilly v. Morse, and this require-
  ment is an eligibility requirement we have applied repeat-
  edly, as explained above. 14
      The second, distinct “how” requirement applies to the
  specification, not the claim: once the required concrete


       14 In O’Reilly, the specification contains a number of
  detailed technical drawings and corresponding descrip-
  tions, which all claims but claim 8 incorporated. See Reis-
  sue Patent No. 117 (issued June 13, 1848) (Figure 1–5 and
  pages 2–3). In contrast, claim 8 of O’Reilly specifically did
  not limit itself to the specification and for that reason was,
  unlike claims 1–7, found ineligible:
       Eighth. I do not propose to limit myself to the spe-
       cific machinery, or parts of machinery, described in
       the foregoing specifications and claims; the essence
       of my invention being the use of the motive power
       of the electric or galvanic current, which I call elec-
       tro-magnetism, however developed, for making or
       printing intelligible characters, letters, or signs, at
       any distances, being a new application of that
       power, of which I claim to be the first inventor or
       discovered.
  O’Reilly, 56 U.S. at 86 (emphasis added). Subsequently,
  the Supreme Court explained that claim 8 in O’Reilly was
  struck down precisely because it “was a claim ‘for a patent
  for an effect produced by the use of electro-magnetism, dis-
  tinct from the process or machinery necessary to produce
  it,’” whereas other claims incorporated the descriptions of
  how to produce the effect. Dolbear v. Am. Bell Tel. Co., 126
  U.S. 1, 534 (1888).
Case: 18-1763    Document: 134      Page: 29     Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS           29
  LLC


  physical structures or actions are set out in the claim, the
  specification must set forth enough information for a rele-
  vant skilled artisan to be able to make and use the claimed
  structures or perform the claimed actions. This is the ena-
  blement requirement, which is distinct from the eligibility
  requirement. 15 Although the word “how” is used in both
  contexts, neither requirement replaces the other. Enable-
  ment is concerned with whether “the specification of a pa-
  tent . . . teach[es] those skilled in the art how to make and
  use the full scope of the claimed invention.” In re Wright,
  999 F.2d 1557, 1561 (Fed. Cir. 1993). Section 101 is con-
  cerned with whether the claims are directed to a natural
  law, not whether the specification has adequately de-
  scribed how to make and use the concretely claimed struc-
  tures and steps. The Supreme Court in Mayo made clear
  that section 101 serves a different function than enable-
  ment. Mayo, 566 U.S. at 90 (“[T]o shift the patent-eligibil-
  ity inquiry entirely to these later [statutory] sections risks
  creating significantly greater legal uncertainty, while as-
  suming that those sections can do work that they are not
  equipped to do.”).
      Fourth, the dissent argues that “[n]o party introduced
  evidence that the desired result of claim 22 (reducing two
  types of vibration) is accomplished by application of
  Hooke’s law and nothing more.” Dissent Op. 11. The dis-
  sent also argues that the claim element “wherein the at
  least one liner is a tuned resistive absorber for attenuating
  shell mode vibrations” of claim 22 “is not achieved by
  Hooke’s law, but rather is achieved by application of a dif-
  ferent natural law—friction damping.” Dissent Op. 13.
  The dissent’s arguments do not alter our conclusion that



      15  In fact, none of the amici, some of whom argued
  that the issue is enablement, attempted to distinguish the
  cases holding claims that state a goal without a solution to
  be patent ineligible. See IPO Br. 6; BIO Br. 9; USIJ Br. 8.
Case: 18-1763      Document: 134    Page: 30     Filed: 07/31/2020




  30        AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                         LLC


  claim 22 in all but name recites Hooke’s Law and nothing
  more to tune the liner to achieve the claimed result of re-
  ducing two types of vibration.
      As the dissent observes, the “directed to” inquiry does
  not look for all natural laws that are “involved” in a claimed
  method. Dissent Op. 6–7. Yet that is the most one can say
  about friction damping in the language of claim 22. What
  claim 22 says is that “tuning a mass and stiffness of at least
  one liner” achieves both the attenuations stated in the
  “wherein” clauses—each of which requires a “tuned”
  liner. 16 Tuning a mass and stiffness, as explained above,
  without further guidance is nothing but an invocation of
  Hooke’s Law.
      Neapco has noted that friction damping is involved in
  a liner’s functioning as “a tuned resistive absorber for at-
  tenuating shell mode vibrations,” but AAM has consist-
  ently taken the position that the invention is the “tuning”
  that achieves this claimed result. AAM Op. Br. 13 (“The
  American Axle inventors . . . conceiv[ed] of the novel and
  unconventional concept of ‘tuning’ a liner to damp specific
  propshaft vibration modes.” (emphasis added)). 17 To be


       16 Claim 22 requires: “tuning a mass and a stiffness
  of at least one liner” “wherein the at least one liner is a
  tuned resistive absorber for attenuating shell mode vibra-
  tions and wherein the at least one liner is a tuned reactive
  absorber for attenuating bending mode vibrations.” ’911
  patent, col. 11, ll. 31–36.
      17  AAM’s expert Dr. Rahn asserted that “[f]riction
  damping is unrelated to . . . ‘tuning a mass and stiffness of
  at least one liner.’” J.A. 1930–31. This is also made clear
  in AAM’s own motion for summary judgement, where it
  stated that “[t]he Asserted Claims are not directed to fric-
  tion damping[,]” explaining that they are limited to “tuned
  liners,” J.A. 4333–34, and that “the Asserted Claims
Case: 18-1763     Document: 134      Page: 31    Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS            31
  LLC


  sure, the tuned liner is in contact with the propshaft, and
  when it is put into use, that contact allows the tuning to
  achieve the desired result of friction damping of the tuning-
  focused frequencies. This is so because, as the district
  court and AAM’s own expert recognized, friction damping
  is a law of nature or natural phenomenon for any contact
  between two surfaces. J.A. 11 (citing and quoting J.A.
  1930). It is the tuning used to create the liner, not the post-
  creation use, that is claimed. And AAM itself has not
  pointed to the role of friction damping in dual-mode atten-
  uation as a reason that the manufacturing claim is not di-
  rected to a natural law under the § 101 test.
      We read the district court as effectively adopting
  AAM’s own view when it recognized that both Hooke’s law
  and friction damping are at least involved but that their
  roles are critically different. The court said that “[t]he
  claimed methods are applications of Hooke’s law with the
  result of friction damping,” J.A. 11 (emphasis added), and
  that friction damping is a “result that is achieved from per-
  forming the method rather than an active step in the
  method.” Id. at 16. Those conclusions accurately reflect
  the role of friction damping in post-manufacturing, un-
  claimed use of the device whose manufacture is what is
  claimed. The recited alleged invention of “tuning a mass
  and a stiffness of at least one liner” does not recite anything
  other than the invocation of Hooke’s law.
      Moreover, AAM could gain nothing by saying that
  claim 22 is directed to both Hooke’s law and friction damp-
  ing. That assertion would simply leave it with a claim


  involve the transformation [of] a liner to a ‘tuned’ liner by
  ‘controlling its mass and stiffness,’ such that the tuned
  liner is both a ‘tuned resistive absorber for attenuating
  shell mode vibrations’ and a ‘tuned reactive absorber for
  attenuating bending mode vibrations,’” J.A. 4336 (empha-
  sis added).
Case: 18-1763       Document: 134    Page: 32    Filed: 07/31/2020




  32      AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                       LLC


  directed to two identified natural laws. J.A. 11 (quoting
  AAM’s expert, at J.A. 1930, stating that friction damping
  “is a property of physics experienced by any two surfaces in
  contact”). If claim 22’s language could be properly inter-
  preted in a way such that it invokes friction damping as it
  does with Hooke’s law, the claim would still on its face
  clearly invoke natural laws, and nothing more, to achieve
  a claimed result.
      Finally, the dissent argues that the majority rejected
  AAM’s step two arguments “with no explanation at all” and
  that “[i]t is inconsistent with precedent to hold claims inel-
  igible without analyzing the step two arguments.” Dissent
  Op. 21. The majority does apply step two. What it con-
  cludes is what this court has elsewhere concluded on ear-
  lier occasions: the only asserted “inventive concept” is
  ineligible subject matter. See BSG Tech, 899 F.3d at 1290;
  Trading Techs., 921 F.3d at 1385; ChargePoint, 920 F.3d at
  775.
                          CONCLUSION
      We affirm as to claim 22 and its asserted dependent
  claims, and as to claim 36, which claim ineligible subject
  matter under § 101. We vacate as to claim 1 and its de-
  pendent claims and remand for further proceedings con-
  sistent with this opinion.
       AFFIRMED IN PART, VACATED IN PART, AND
                     REMANDED
                             COSTS
        No costs.
Case: 18-1763    Document: 134      Page: 33   Filed: 07/31/2020




    United States Court of Appeals
        for the Federal Circuit
                   ______________________

     AMERICAN AXLE & MANUFACTURING, INC.,
                Plaintiff-Appellant

                               v.

   NEAPCO HOLDINGS LLC, NEAPCO DRIVELINES
                     LLC,
              Defendants-Appellees
             ______________________

                         2018-1763
                   ______________________

      Appeal from the United States District Court for the
  District of Delaware in No. 1:15-cv-01168-LPS, Chief Judge
  Leonard P. Stark.
                    ______________________

  MOORE, Circuit Judge, dissenting.
       The majority’s decision expands § 101 well beyond its
  statutory gate-keeping function and collapses the Al-
  ice/Mayo two-part test to a single step—claims are now in-
  eligible if their performance would involve application of a
  natural law. The majority makes three critical errors of
  law and in doing so, has inflated § 101 beyond the statutory
  language and Supreme Court precedent. First, the major-
  ity finds claims directed to natural laws, yet they clearly
  contain no such natural law. The majority creates a new
  test for when claims are directed to a natural law despite
  no natural law being recited in the claims, the Nothing
  More test. The majority refuses to ask the parties for
Case: 18-1763     Document: 134      Page: 34    Filed: 07/31/2020




  2       AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                       LLC


  supplemental briefing on the application of its new Nothing
  More test or to remand to the district court to assess the
  applicability of the new test in the first instance. The ma-
  jority instead holds that we appellate judges, based on our
  background and experience, will resolve questions of sci-
  ence de novo on appeal. We will determine whether
  Hooke’s law and nothing more results in a reduction of two
  types of vibration in a propshaft. The majority reaches this
  conclusion despite all of the briefing and record evidence
  contradicting it. Second, the majority refuses to consider
  the unconventional claim elements. Third, the majority
  has imbued § 101 with a new superpower—enablement on
  steroids. The majority’s blended 101/112 analysis expands
  § 101, converts factual issues into legal ones and is certain
  to cause confusion for future cases.
      The claims at issue contain a specific, concrete solution
  (inserting a liner inside a propshaft) to a problem (vibra-
  tions in propshafts). Although some degree of trial and er-
  ror in modifying the mass, stiffness, and location of the
  liner to optimize the reduction in vibration of a given shaft
  could (if undue) create an enablement concern, that is not
  a § 101 problem. American Axle (AAM) and the many
  amici believe each of these errors of law are likely to create
  confusion for the district courts and to expand § 101 pro-
  foundly. 1 I agree.



      1    See, e.g., USIJ Br. at 1 (“The panel decision, if al-
  lowed to stand, will add further confusion to a body of ju-
  risprudence regarding patent eligibility that already has
  proven to be difficult if not wholly impenetrable to apply
  with any consistency.”); id. at 5 (quoting Alice) (“The ma-
  jority decision, in short, threatens to ‘swallow all of patent
  law,’ because ‘at some level, all inventions . . . embody, use,
  reflect, rest upon, or apply laws of nature, natural phenom-
  ena, or abstract ideas.’”); IPO Br. at 8 (“the decision has the
Case: 18-1763     Document: 134      Page: 35    Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS             3
  LLC


      The majority claims this is a narrow decision—I think
  not. This case turns the gatekeeper into a barricade. Un-
  stated natural laws lurk in the operation of every claimed
  invention. Given the majority’s application of its new test,
  most patent claims will now be open to a § 101 challenge
  for being directed to a natural law or phenomena.
       Finally, though not a legal question, I am troubled by
  the deprivation of property rights without due process. The
  majority declares claims representative despite the fact
  that no party argued below or to this court that there were
  representative claims, and AAM argued the import to the
  § 101 analysis of dependent claim limitations throughout
  these proceedings. And the majority finds against the pa-
  tentee by reaching a claim construction issue of the major-
  ity’s own creation. The majority concludes, though no
  party argued it at any point in this litigation or appeal, that
  the claim terms “positioning” and “inserting” have different
  meanings. And only because of its newly proffered, com-
  pletely sua sponte construction, claim 22 is deemed ineligi-
  ble. There is simply no justification for the majority’s
  application of its new Nothing More test other than result-
  oriented judicial activism. This is fundamentally unfair. I
  dissent from this unprecedented expansion of § 101.
     I. THESE CLAIMS ARE NOT DIRECTED TO A NATURAL LAW
            A. The majority’s expansion of “directed to”
      The ’911 patent, directed to a method of manufacturing
  a drive shaft assembly for a car, is the type of traditional
  manufacturing patent of automotive parts which has been


  potential to blur the lines between the section 101 and 112
  analysis. This will increase confusion and uncertainty in
  the law of patent eligibility and could open the door to hy-
  brid eligibility and written description-enablement argu-
  ments.”); BIO Br. at 2 (“it is now Section 101 that has
  engulfed the other statutory sections”).
Case: 18-1763     Document: 134      Page: 36    Filed: 07/31/2020




  4     AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                     LLC


  eligible for patent protection since the invention of the car
  itself. “Industrial processes such as this are the types
  which have historically been eligible to receive the protec-
  tion of our patent laws.” Diamond v. Diehr, 450 U.S. 175,
  184 (1981).
      The majority’s holding that these claims to manufac-
  turing an automotive drive shaft are ineligible has sent
  shock waves through the patent community. “It’s unthink-
  able the courts found this invention, a manufacturing pro-
  cess for making a key automotive part, as patent
  ineligible.” Rep. Doug Collins. American Axle is a “poster
  child for how the current test for patent eligibility is being
  applied to reach rather absurd results.” Perry Cooper, Ball
  in Federal Circuit’s Court on Patent Eligibility Clarity,
  Bloomberg News (Jan. 30, 2020) (quoting Professor David
  Taylor). “[I]f ‘industrial-process,’ physically-based patents
  like these are ineligible under Mayo/Alice, then seemingly
  every patent is in ineligibility jeopardy.” Michel Br. at 7.
  “‘The optics are challenging for this, because you’re talking
  about a way to make a drive shaft for a car, and that sounds
  like the kind of thing that’s been getting patented for 100
  years,’ . . . The decision brings to the foreground an issue
  that has been bubbling in patent eligibility cases for some
  time, which is that every invention at some level operates
  according to natural laws.” Ryan Davis, Drive Shaft Rul-
  ing May Expand Challenges to Patent Eligibility, Law 360
  (Oct. 24, 2019). “This is a specific, practical application of
  the laws of thermodynamics in an industrial process—an
  innovative process deemed patentable by the courts since
  the nineteenth century.” Law Profs. Br. at 4. See also Mi-
  chael Cicero, Patent Ineligibility Defense Expands to Me-
  chanical Subject Matter, Bloomberg News (Dec. 4, 2019);
  Jonathan Osha, American Axle: The Latest Twist of Patent
  Eligibility Oshaliang Newsletter (Oct. 17, 2019) (American
  Axle is “a new low in patent eligibility jurisprudence . . . if
  a method of manufacturing a propeller shaft is not eligible
Case: 18-1763    Document: 134      Page: 37     Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS            5
  LLC


  subject matter, it is difficult to imagine where a future line
  might be drawn.”). 2 These claims do not preempt use of a
  natural law and the majority significantly broadens the di-
  rected to test to find otherwise.
       In this case, the natural law which the claims are pur-
  portedly directed to has been a constantly moving target.
  Neapco argued and its expert testified that claim 22 was
  directed to the application of two natural laws working to-
  gether to achieve the claimed reductions in vibration:
  Hooke’s law (which reduces bending mode vibration) and
  friction damping (which reduces shell mode vibration). The
  district court held that claim 22 is directed to “laws of na-
  ture: Hooke’s law and friction damping.’” J.A. 10. On ap-
  peal, Neapco continues to assert that claim 22 is directed
  to the application of two natural laws:
      Hooke’s Law and friction damping are two separate
      laws of nature. Indeed, the [district court] opinion
      states that “the issue presented is whether the As-
      serted Claims as a whole are directed to laws of na-
      ture: Hooke’s law and friction damping.”
  Neapco Br. at 56 (emphasis in original). The prior majority
  opinion in this case explained that the claimed invention is
  “more complex than just a bare application of Hooke’s Law,
  and that other natural laws may be relevant.” Prior Maj.
  at 20. It further explained that the claims are directed to
  “Hooke’s law and possibly other natural laws.” Id.




      2   “Amici once proposed as a reductio ad absurdum
  that even an automobile engine can be framed as a mere
  application of the laws of thermodynamics and thus
  deemed unpatentable. Adam Mossoff, A Brief History of
  Software Patents (and Why They’re Valid), 56 Ariz. L. Rev.
  65, 71 (2014). The panel majority decision has made this
  absurdity a legal reality.” Law Prof. Br. at 3.
Case: 18-1763    Document: 134      Page: 38     Filed: 07/31/2020




  6     AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                     LLC


       Changing course on rehearing, the majority now con-
  cludes claim 22 is directed to Hooke’s law and only Hooke’s
  law “because it simply requires the application of Hooke’s
  law to tune a propshaft liner to dampen certain vibrations.”
  Maj. at 9. And revising history, the majority now claims
  that the district court itself held that the claims were di-
  rected to Hooke’s Law and nothing more. Maj. at 7. This
  is contrary to both parties’ understanding about the dis-
  trict court’s holding and the majority’s own prior conclusion
  about the district court’s holding:
      “The district court concluded that ‘the Asserted
      Claims as a whole are directed to laws of nature:
      Hooke’s Law and friction damping. J.A. 10.’”
  Prior Maj. at 7. Attempting to revise history is not good:
  “The past was erased, the erasure was forgotten, the lie be-
  came the truth.” GEORGE ORWELL, 1984.
        1. The majority’s holding conflicts with precedent
      The majority’s holding is in direct conflict with our
  precedent and a dramatic expansion of § 101. As we have
  explained,
      The “directed to” inquiry . . . cannot simply ask
      whether the claims involve a patent-ineligible con-
      cept, because essentially every routinely patent-el-
      igible claim involving physical products and
      actions involves a law of nature and/or natural phe-
      nomenon—after all, they take place in the physical
      world. Rather, the ‘directed to’ inquiry applies a
      stage-one filter to claims, considered in light of the
      specification, based on whether “their character as
      a whole is directed to excluded subject matter.”
  Enfish LLC v. Microsoft Corp., 822 F.3d 1327, 1335 (Fed.
  Cir. 2016) (citations omitted). “[A]t step one, it is not
  enough to merely identify a patent-ineligible concept un-
  derlying the claim; we must determine whether that pa-
  tent-ineligible concept is what the claim is directed to.’’
Case: 18-1763    Document: 134      Page: 39     Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS            7
  LLC


  ChargePoint, Inc. v. SemaConnect, Inc., 920 F.3d 759, 766
  (Fed. Cir. 2019) (internal citations omitted). A claim is not
  directed to a natural law simply because it touches upon,
  implicates, uses or involves a natural law.
      The majority cites Diehr, Flook, O’Reilly, and Mayo as
  supporting its conclusion that these claims are directed to
  a natural law. But, in each of those cases, the natural law
  was undeniably, expressly articulated in the claim. “When
  a claim recites a mathematical formula (or scientific prin-
  ciple or phenomena of nature), an inquiry must be made
  into whether the claim is seeking patent protection for that
  formula in the abstract.” Maj. at 18 (quoting Diehr). One
  important difference between this natural law case and
  every other one ever decided is that these claims do not ac-
  tually recite any particular natural law and likely impli-
  cate many (as all mechanical inventions must comply with
  the laws of physics).
       Claim 22 does not recite a natural law, about that there
  can be no doubt. Hooke’s law is not mentioned by name or
  formula anywhere in the claims, specification or prosecu-
  tion history. The majority overcomes this defect by articu-
  lating a new test (the Nothing More test) for when a claim
  is directed to a natural law despite not reciting one:
      This holding as to step 1 of Alice extends only
      where, as here, a claim on its face clearly invokes a
      natural law, and nothing more, to achieve the
      claimed result.
  Maj. at 21. The majority explains that claim 22 is directed
  to Hooke’s law because the tuning element in claim 22 in-
  cludes “controlling the mass and stiffness . . . Thus, claim
  22 requires use of a natural law.” Maj. at 11–12. Every
  mechanical invention requires use and application of the
  laws of physics. It cannot suffice to hold a claim directed to
  a natural law simply because compliance with a natural
  law is required to practice the method.
Case: 18-1763    Document: 134      Page: 40    Filed: 07/31/2020




  8       AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                       LLC


      Section 101 is monstrous enough, it cannot be that use
  of an unclaimed natural law in the performance of an in-
  dustrial process is sufficient to hold the claims directed to
  that natural law. The majority’s only citation in support of
  this dramatic expansion of our law is an English case from
  1841, Neilson v. Harford, Webster’s Patent Cases 295, 371
  (1841). There was no claim in Neilson as claiming practice
  did not exist and the English court actually held the patent
  eligible: “the plaintiff does not merely claim a principle,
  but a machine embodying a principle.” Id. 3 I cannot dis-
  cern the logic in the majority’s suggestion that this English
  case supports its decision to depart from existing U.S. prec-
  edent. It cannot be that a claim is directed to a natural law
  when there is no specific natural law discernable in the
  claim or even the specification. All physical methods must
  comply with, and apply, the laws of physics and the laws of
  thermodynamics. The fact that they do does not mean the
  claims are directed to all such laws.
      The majority also attempts to justify its result by com-
  paring claim 22 to claim 8 in O’Reilly. Claim 8 in O’Reilly
  reads:
      Eighth. I do not propose to limit myself to the spe-
      cific machinery or parts of machinery described in
      the foregoing specification and claims; the essence
      of my invention being the use of the motive power


      3    The majority claims that in O’Reilly and Mayo, the
  Supreme Court held that in Neilson the principle “was not
  in the patent but was embodied in th[e described] ma-
  chine.” Maj. at 27. Neither decision holds nor indicates
  that the principle was not disclosed in the patent. When
  discussing Neilson, the Supreme Court stated: “the claimed
  process included not only a law of nature but also several
  unconventional steps . . . that confined the claims to a par-
  ticular, useful application of the principle.” Mayo, 566 U.S.
  at 84.
Case: 18-1763     Document: 134      Page: 41     Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS              9
  LLC


      of the electric or galvanic current, which I call elec-
      tromagnetism, however developed for marking or
      printing intelligible characters, signs, or letters, at
      any distances, being a new application of that
      power of which I claim to be the first inventor or
      discoverer.
  56 U.S. (15 How.) 62, 112 (1854). The Supreme Court held
  claim 8 ineligible because the claim was not limited to “spe-
  cific machinery or parts of machinery described,” but in-
  stead claimed electromagnetism [(the natural phenomenon
  was actually articulated in the claim)] developed by any
  means to mark or print at any distance. Id. The Supreme
  Court’s concern was not, as the majority contends, that an
  artisan would not know “how” to print at any distance us-
  ing electromagnetism. The concern was that Morse’s claim
  8 was not limited to any specific “process or machinery,”
  and that the expressly limitless claim would preclude
  “some future inventor . . . [who] discover[s] a mode of writ-
  ing or printing at a distance by means of the electric or gal-
  vanic current, without using any part of the process or
  combination set forth in the plaintiff's specification” from
  practicing his invention. Id. at 112–113. Unlike Morse
  claim 8, claim 22 does not preclude all use of, or even ex-
  pressly recite, the natural law and it does expressly artic-
  ulate the “machinery” used to achieve the result of
  dampening specific vibrations—the liner.
       Amici are understandably troubled, as am I, by the ma-
  jority’s departure from existing § 101 precedent. “The
  panel seems to conclude that step one can be satisfied even
  if the natural law, or laws, at issue are not identi-
  fied. . . . General and non-specific statements should not be
  enough to satisfy step one.” IPO Br. at 8–9. “The specifi-
  cation invokes Hooke’s Law no more than it does the law of
  gravity . . . the majority elected to sweep into its analysis
  one or more unidentified natural laws in addition to
  Hooke’s Law in order to assert that the claims were indeed
  ‘directed to’ some number of natural laws.” BIO Br. at 6.
Case: 18-1763        Document: 134    Page: 42    Filed: 07/31/2020




  10        AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                         LLC


  “Just because an invention operates according to laws of
  nature (as all inventions must) cannot mean that it is ‘di-
  rected to’ these laws.” BIO Br. at 7.
           2. The majority’s new Nothing More test leaves the
              science to the appellate judges to decide de novo
      The majority’s Nothing More test, like the great Amer-
  ican work The Raven from which it is surely borrowing,
  will, as in the poem, lead to insanity. The majority has
  concluded that on appeal, as a matter of law, we judges can
  decide as a matter of physics whether claim 22’s results—
  attenuating two types of vibration—are accomplished by
  Hooke’s law and nothing more. To say this feels like a bit
  of an overreach is an understatement. Today, contrary to
  all arguments in the case, the record, the district court’s
  decision, and its own prior opinion, the majority concludes
  that claim 22 is directed to “Hooke’s law and nothing more,”
  to accomplish the claimed results of reducing two kinds of
  vibrations.
       The district court did not hold that claim 22’s results—
  attenuated shell mode vibration and bending mode vibra-
  tion in the propshaft—were achieved by Hooke’s law and
  nothing more. In fact, as the majority previously recog-
  nized, the district court clearly held that they were
  achieved by the combination of Hooke’s law and friction
  damping. Prior Maj. at 7. Neither party argued that claim
  22 is directed to Hooke’s law and nothing more. Even
  Neapco argued it was the combination of Hooke’s law and
  friction damping, “two separate natural laws” which ac-
  complished the claimed vibration damping. Neapco Br. at
  56. 4



       4  In its summary judgment briefing Neapco argued
  that claim 22 was directed to “well-known laws of physics,”
  including both Hooke’s law and “the law of nature or
Case: 18-1763     Document: 134      Page: 43     Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS             11
  LLC


      No party introduced evidence that the desired result of
  claim 22 (reducing two types of vibration) is accomplished
  by application of Hooke’s law and nothing more. In fact,
  both parties’ experts expressly and unequivocally testified
  to the contrary. 5 All evidence in this case is to the contrary.


  natural phenomenon for friction damping.” J.A. 1248–50.
  On appeal, Neapco likewise argues that the claims are “di-
  rected to natural laws (Hooke’s laws and the law of friction
  damping).” Neapco Br. at 30. Neapco leaves no doubt
  when responding to AAM’s argument:
      “[The district court opinion] states that Hooke’s law
      and friction damping are two separate laws of na-
      ture. Indeed, the opinion states that ‘the issue pre-
      sented is whether the Asserted Claims as a whole
      are directed to laws of nature: Hooke’s law and
      friction damping.’ The opinion goes on to accu-
      rately describe Hooke’s law . . . [and] observed that
      friction damping, a separate law of nature, ‘is a
      property of physics experience by two surfaces in
      contact.’”
  Id. at 56.
      5   AAM’s expert testified that Hooke’s law is not re-
  quired to practice claim 22 nor is application of Hooke’s law
  sufficient to practice claim 22:
      Nor do any of the above claim limitations (and their
      constructions) require the application of Hooke’s
      law or any variation thereof. Hooke’s law is simply
      a linear relationship between the force F and dis-
      placement x of a spring with stiffness k. Taking
      the first limitation as an example, e.g., “tuning a
      mass and stiffness of at least one liner,” claim 22
      involves a method having the step of “controlling a
      mass and stiffness of at least one liner to configure
Case: 18-1763     Document: 134      Page: 44     Filed: 07/31/2020




  12     AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                      LLC


  “The testimony of opposing technical experts was refresh-
  ingly harmonious; perhaps because these principles of clas-
  sical electricity are beyond debate.” Perkin-Elmer Corp. v.
  Westinghouse Elec. Corp., 822 F.2d 1528, 1536 (Fed. Cir.
  1987) (Newman, J., dissenting).
      Lest there be any doubt, the accused infringer’s
  (Neapco’s) expert analyzes claim 22’s three claim elements
  related to reducing vibrations:
       1. “tuning a mass and a stiffness of at least one
       liner;”
       2. “wherein the at least one liner is a tuned reactive
       absorber for attenuating bending mode vibrations;”
       and
       3. “wherein the at least one liner is a tuned resis-
       tive absorber for attenuating shell mode vibra-
       tions.”
  J.A. 1602–05, ¶¶ 172–79. Neapco’s expert testifies that the
  first two elements can be achieved by application of
  Hooke’s law and nothing more:
       176. Thus, the phrase “tuning a mass and a stiff-
       ness of at least one liner” claims Hooke’s law. Sim-
       ilarly, the claim element “tuned reactive absorber
       for attenuating bending mode vibrations” claims
       nothing more than Hooke’s law again, how one
       body will react to the mass spring mass damper.




       the liner to match a relevant frequency or frequen-
       cies.” One can perform that step, like the other
       steps of claim 22, without considering, applying, or
       even knowing of Hooke’s law.
  J.A. 1928. Experts for both sides agree that claim 22 is not
  directed to Hooke’s law and nothing more.
Case: 18-1763    Document: 134      Page: 45     Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS            13
  LLC


  However, when it comes to the third element (reducing
  shell mode vibration), this expert is crystal clear that it is
  not achieved by Hooke’s law, but rather is achieved by ap-
  plication of a different natural law—friction damping:
      177. Similarly, the claim element “tuned resistive
      absorber for attenuating shell mode vibrations”
      claims nothing more than the law of nature/natural
      phenomenon for friction damping. Friction damp-
      ing has been modeled as both Coulomb damping
      and viscoelastic damping which occur due to the re-
      sistive friction and interaction of two surfaces that
      press against each other as a source of energy dis-
      sipation.
  Shell mode vibration, according to Neapco, is reduced by
  insertion of the liner into the propshaft in a manner to
  cause a press fit which will reduce shell mode vibrations by
  friction damping.
      Neapco’s expert directly contradicts the majority’s cur-
  rent conclusion. His opinion is that claim 22 is directed to
  and requires application of two different natural laws to
  achieve the result of reducing two types of vibration in the
  propshaft:
      179. In short, the claimed invention claims nothing
      more than the law of nature and/or natural phe-
      nomenon of Hooke’s Law and friction damping.
  Rather than address these, the parties’ arguments, as we
  are bound to do as appellate judges, the majority recasts
  these arguments as “the dissent’s arguments” and dis-
  misses them in conclusory fashion. 6 The majority claims



      6   In an attempt to deflect and cause confusion, the
  majority cites AAM’s arguments that claim 22 is not di-
  rected to friction damping or any other natural law. First,
Case: 18-1763    Document: 134      Page: 46    Filed: 07/31/2020




  14    AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                     LLC


  that the “most one can say about friction damping in the
  language of claim 22” is that it is merely “involved” in the
  claimed method. 7 Maj. at 30. Not only can the parties and
  the district court say more, they did. The parties and their
  experts uniformly agree that the claims are not directed to
  Hooke’s law and nothing more. The majority’s conclusion
  to the contrary, without so much as acknowledging the par-
  ties’ arguments or evidence, casts a cloud of confusion not
  just over the bounds of this case, but over our role as
  judges. The majority’s conclusion that Hooke’s law and
  nothing more reduces two types of vibration in propshafts
  amounts to a clear rule of law—judges, not experts, will de-
  termine as a matter of law, when claims are directed to a
  natural law and nothing more. We are the scientific ex-
  perts now. Whether Hooke’s law and nothing more
  achieves reduction in two types of vibration in propshafts
  should be a question of fact, but the majority concludes oth-
  erwise. It decides this question of physics as a matter of


  AAM has not been given an opportunity to respond to the
  majority’s new Nothing More test. Second, AAM’s argu-
  ment that claim 22 is not directed to or preempts friction
  damping does not in the least support the majority’s con-
  clusion that Hooke’s law and nothing more achieves the re-
  duction of two types of vibrations. Finally, even if this
  twisted logic could be followed, it would at most create a
  question of fact about which the parties disagree and it
  would thus be improper to grant summary judgment.
      7   Acknowledging in the end, that Hooke’s law alone
  may not achieve the reduction of two types of vibration, the
  majority pivots and states that the claim is still ineligible
  if multiple unclaimed natural laws working together are
  used to achieve the claimed results. Maj. at 31–32. The
  majority’s conclusion that a claim is ineligible because mul-
  tiple unclaimed natural laws could be involved in achieving
  the claimed results is an incredibly broad ruling and will
  invite a § 101 challenge in every case.
Case: 18-1763     Document: 134      Page: 47    Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS            15
  LLC


  law on appeal in the first instance even at summary judg-
  ment.
      The majority also holds that determining whether a
  claim “invokes” a natural law, though no natural law is ar-
  ticulated in the claim is also a question of law for the court
  to decide. It is undisputed that claim 22 does not mention
  a natural law either by name or formula. Since Hooke’s
  law is not mentioned by name or formula anywhere in the
  intrinsic record, how can we conclude, as a matter of law,
  the claim nonetheless clearly invokes Hooke’s law?
       As appellate judges, we are well-equipped to discern
  meaning from legal documents. But things get murkier as
  we muddle our way into the intersection of science and the
  law. Thus, the Supreme Court has wisely announced a line
  between that which we can evaluate de novo (the intrinsic
  record, composed largely of legal documents) and that
  which we cannot (everything extrinsic to the record, includ-
  ing expert testimony). See Teva Pharm. USA, Inc. v.
  Sandoz, Inc., 574 U.S. 318, 324–28 (2015); see also Aatrix
  Software, Inc. v. Green Shades Software, Inc., 882 F.3d
  1121, 1125 (Fed. Cir. 2018); Berkheimer v. HP Inc., 881
  F.3d 1360, 1365 (Fed. Cir. 2018). Where, as here, nothing
  in the intrinsic record so much as mentions Hooke’s law,
  we are unquestionably in the extrinsic category. There is
  nothing in the ’911 patent that “clearly invokes a natural
  law.” Yet the majority concludes, as if it would be apparent
  to anyone who looked, that the claim limitations equal
  Hooke’s law. One can reach such a conclusion only through
  factfinding based on expert testimony. But judges are not
  fact or technical experts. The only appropriate fact finder
  is the district court and not on summary judgment.
       If we are going to embark in a tumultuous area of law
  on a new test for ascertaining when claims are directed to
  unmentioned natural laws—we should do so with the ben-
  efit of briefing or even better, we should remand for the
  district court to apply the test in the first instance since it
Case: 18-1763    Document: 134      Page: 48    Filed: 07/31/2020




  16    AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                     LLC


  requires resort to extrinsic evidence. Future cases will use
  this case as a template for how judges can determine as a
  matter of law when a claim invokes an unmentioned natu-
  ral law and nothing more. All aspects are henceforth a
  question of law and the record is irrelevant. We are the
  experts and we will determine when a claim invokes an un-
  mentioned natural law and when nothing but that natural
  law is necessary to achieve the claimed results.
      A disturbing amount of confusion will surely be caused
  by this opinion, which stands for the proposition that
  claims can be ineligible as directed to a natural law even
  though no actual natural law is articulated in the claim or
  even the specification. The majority holds that claims are
  directed to a natural law if performance of the claimed
  method would use the natural law. The majority has
  “open[ed] the door to countless challenges to mechanical in-
  ventions with underpinnings in one or more, potentially
  unnamed natural laws.” IPO Br. at 9. Holding these
  claims ineligible under a purported natural law analysis
  “leaves patentees awash in a sea of uncertainty; how can
  one determine if a claim is directed to a natural law with-
  out a natural law being apparent either on the face of the
  claim, or under a proper claim construction?” BIO Br. at 5.
  And the majority’s addition of its Nothing More test will
  add nothing more to the clarity. As we see in this case, the
  Nothing More test can be met even when all of the argu-
  ments and evidence are to the contrary and will not be fi-
  nally resolved until we judges bring our scientific acumen
  to bear on the questions.
                   B. Claim 1 vs. Claim 22
      The majority holds that claim 1 is not directed to a nat-
  ural law (Hooke’s law) because of the additional positioning
  limitation and the possible inclusion of variables other
  than mass and stiffness in the tuning limitation of claim 1.
  Maj. at 24–25. I agree that claim 1 is not directed to a nat-
  ural law. I would, however, reverse rather than vacate
Case: 18-1763     Document: 134      Page: 49    Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS            17
  LLC


  because under the second step of the Alice/Mayo test, there
  are at least factual questions regarding this claim’s in-
  ventive concepts which preclude summary judgment. See
  infra Part II. Since we are remanding, the district court
  will have an opportunity to address these fact questions re-
  garding claim 1 in the first instance.
       To hold claim 22 ineligible, the majority holds that
  claim 22’s inserting limitation is not equivalent to claim 1’s
  positioning limitation “and AAM never argued otherwise.”
  Maj. at 25 n.13. The majority is sua sponte interpreting
  undisputed, unappealed claim terms with reference to
  nothing. They do not cite the patent, the prosecution his-
  tory, or any briefs. Neither party ever suggested that the
  inserting and positioning limitations had different mean-
  ings. Claim 22 requires tuning and inserting wherein the
  liner will function as a tuned resistive absorber (damp shell
  mode) and a tuned reactive absorber (damp bending mode).
  AAM argued in its Opening Brief that the location of the
  liner within the shaft was a characteristic which impacted
  attenuation of vibration. See, e.g., AAM Opening Br. at 64–
  65 (“The ’911 patent specifically teaches how to control the
  characteristics of a liner to not only match but damp rele-
  vant propshaft vibrations, including the thickness of the
  liner, the interference fit, the location of the liner”). “One
  liner characteristic that can be controlled—‘location of the
  liners 204 within the shaft member 200’—is independent
  of its structure, e.g., its mass and stiffness.” Id. at 42; see
  also Oral Arg. at 1:36–2:00 (“The specification tells you,
  here’s what you control, you control the diameter of the
  liner, the thickness of it, where you place the liner, location
  is important.”). Neapco’s own expert explained that shell
  mode vibration is reduced by the fit achieved when the
  liner is inserted into the propshaft. The majority’s sua
  sponte appellate claim construction is improper, unfounded
  and unsupported by the record. It is not our job on appeal
  to create our own claim construction issues to hold claims
Case: 18-1763     Document: 134      Page: 50    Filed: 07/31/2020




  18     AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                      LLC


  ineligible especially when they were never briefed or ar-
  gued by the parties.
    II. UNCONVENTIONAL CLAIM ELEMENTS RENDER A CLAIM
                ELIGIBLE EVEN IF IT FAILS STEP ONE

      Even if the majority’s analysis of the claims satisfied
  step one of the Alice/Mayo test, which it did not, there is a
  step two. Step two is a required inquiry precedent to hold-
  ing that claims are ineligible for patenting. The claims will
  not be held ineligible (remember § 101 is meant to be a
  gatekeeper) if the claims contain an “inventive concept.”
  There are many here, articulated in the claims themselves,
  about which there exist at least questions of fact which
  should have precluded summary judgment. Argued below
  and throughout the appeal, AAM maintains that liners had
  never been used to reduce bending mode vibration. See
  AAM Br. at 12, 25–26, 27, 35, 57–60, 63, and 65 n.5; AAM
  Reply Br. at 2, 15 (“Prior art liners were used to provide
  general broadband damping of shell mode vibrations, but
  liners were not used to dampen bending mode vibrations
  prior to the claimed invention.”); Id. at 19 (“It was inventive
  to use a liner to damp bending mode vibrations”); Id. at 24–
  25, and 29. The argument that liners were never before
  used to attenuate bending mode vibrations was AAM’s first
  and one of its strongest non-conventionality arguments.
  Only to be bolstered by additional strong, fact-based, argu-
  ments such as the unconventional use of liners to attenuate
  multiple vibration modes and unconventional control of
  characteristics (including mass, stiffness and location) to
  damp vibration. AAM’s opening brief set these forth on the
  very first page of its step-two argument:
       1. The Claims Contain Inventive Concepts and
       Are Not Conventional or Routine
                            *   *    *
       [T]he asserted claims include at least the following
       inventive concepts:
Case: 18-1763    Document: 134     Page: 51   Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS          19
  LLC


         •   using a cardboard liner to reduce
             bending mode vibrations;
         •   using a cardboard liner to reduce bending
             and shell mode vibrations;
         •   tuning a cardboard liner by controlling its
             characteristics;
         •   controlling the characteristics of a card-
             board liner such that it matches and damps
             bending mode vibrations;
         •   controlling the characteristics of a card-
             board liner such that it damps bending
             mode vibrations by oscillating in opposition
             to a specific propshaft bending mode fre-
             quency; and
         •   controlling the characteristics of a card-
             board liner such that it matches and damps
             vibration of multiple different types of
             propshaft vibration, e.g., both bending and
             shell mode vibrations.
  AAM Br. at 57–58.
      The patent discloses prior use of plugs, weights, and
  dampers to attenuate bending mode vibrations, but
  stresses that liners were not used. ’911 patent at 2:29–38.
  AAM explained that before the ’911 patent, liners were not
  used to damp bending mode vibrations, instead car manu-
  facturers shoved masses of wadded up cardboard into the
  propshaft. Oral Arg. 6:46–7:11. More than a dozen times
  in the briefs and during oral argument AAM argued that
  the use of liners to attenuate bending mode vibration was
  one of its inventive concepts. During oral argument, AAM
  corrected the court when a member of the majority tried to
  suggest that liners to attenuate bending mode were known
  in the prior art:
Case: 18-1763     Document: 134      Page: 52    Filed: 07/31/2020




  20       AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                        LLC


       Judge: “None of that is new, there were liners,
       there were changes to the liners to make them
       dampen, right? That was not new.”
       AAM: “The liners had never been used to damp
       bending mode.”
  Oral Arg. 6:37–49. Even Neapco acknowledged that the
  patent states that liners had not been used to attenuate
  bending mode vibrations. See Neapco Br. at 8. 8 It matters
  not at all to the majority that AAM alleges that liners had
  not been used to reduce bending mode vibration, nor that
  Neapco presented no contrary evidence. This majority
  opinion ignores this step two argument entirely—it never
  addresses it.
       In its prior decision, the majority did address AAM’s
  argument that one of its inventive concepts was to use lin-
  ers to reduce bending mode vibrations: it suggested that
  AAM did not make this argument, Prior Maj. at 12 n.3, it
  made its own fact finding based on evidence not of record
  that liners were used to attenuate bending mode vibra-
  tions, id., and then finally, it held (contrary to Alice/Mayo),
  “it makes no difference to the section 101 analysis whether
  the use of liners to attenuate bending mode vibrations was
  known in the art,” id. Each of these positions has been
  abandoned today, but the result is the same—this time
  with no explanation at all. It is inconsistent with precedent



       8   Though Neapco admits that the patent asserts lin-
  ers had never been used to attenuate bending mode, it ar-
  gues that whether it was previously unknown to use a liner
  to attenuate bending mode is “a point that Neapco disputes
  and the record evidence contradicts.” Neapco Br. at 36.
  Given Berkheimer, this, on its face, at least creates a ques-
  tion of fact regarding step two which should have precluded
  summary judgment of ineligibility. Berkheimer v. HP Inc.,
  881 F.3d 1360 (Fed. Cir. 2018).
Case: 18-1763    Document: 134      Page: 53     Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS           21
  LLC


  to hold claims ineligible without analyzing the step two ar-
  guments. 9
       In Mayo, the Supreme Court reflected on the process of
  updating alarm limits held ineligible in Flook. The Flook
  claims recited a mathematical formula and did not explain
  how the variables used in the formula were to be selected.
  556 U.S. at 81. The Court did not stop at step one, it con-
  sidered the inventiveness of every single claim limitation,
  and only after concluding that they were all “well-known”
  held that “there was no inventive concept in the claimed
  application of the formula.” Id. at 82. In contrast, the ma-
  jority stops at step one.
      According to the majority, “[w]hat is missing is any
  physical structure or steps for achieving the claimed re-
  sult.” Maj. at 15. The majority never addresses whether a
  claim to using a physical, hollow liner inserted inside a hol-
  low drive shaft to attenuate bending mode vibrations in the
  shaft (yes these are all express claim limitations), was con-
  ventional. Much less whether a claim to using the same
  physical liner to attenuate both bending mode and shell
  mode vibrations was conventional. The result is not, as the
  majority claims, a tuned liner; the result is the reduction of
  vibration in the propshaft. And these claims expressly re-
  quire the reduction of bending mode and shell mode vibra-
  tions employing a liner positioned inside the hollow shaft,
  which according to AAM had never been done before.
  Goodness sakes, the dependent claims held ineligible by
  the majority specify the material the liner must be made of
  (cardboard or plastic or fiberglass or metal (claim 31)) and
  the actual physical form it must take (extending helically


      9   The majority states in generality only that “a
  claimed invention’s use of the ineligible concept to which it
  is directed cannot supply the inventive concept.” Maj. at
  21–22. AAM has never claimed that its inventive concept
  is Hooke’s law (the ineligible natural law).
Case: 18-1763     Document: 134      Page: 54    Filed: 07/31/2020




  22    AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                     LLC


  (claim 27), with fingers (claim 33), circumferentially
  wrapped (claim 29) or over-molded (claim 32)) and the
  place the liners must be positioned (“symmetrically about
  a bending anti-node” (claims 34, 35)). See also Oral Arg. at
  29:39–57 (“The claims talk about not only specific locations
  you put it at anti-nodes for specific modes. The dependent
  claims also include that they have to be directed to the sec-
  ond bending mode or the second shell mode.”). It is remark-
  able that the majority thinks that claims with all of these
  very physical, very concrete, very structural limitations are
  “missing any physical structure or steps.” A fiberglass
  liner with a helically shaped resilient member extending
  circumferentially around the liner or over-molded to the
  structural portion of the liner certainly feels like the “phys-
  ical structure” that the majority says is missing from the
  claims.
      AAM alleges throughout that the concept of tuning a
  liner, i.e. controlling the characteristics of a liner to
  dampen vibration of a given system is also an inventive
  concept. See id. at 27–28 and 57–67; AAM Reply Br. at 2,
  16, and 18–29. The particular characteristics of the tuned
  liner will depend on the characteristics of the propshaft it
  is being used in (for example the natural frequencies,
  which are inherent properties of each shaft). See ’911 pa-
  tent at 7:44–55; AAM Br. at 4, 6, 46, and 53. And the ’911
  patent’s specification explains how to tune liners to atten-
  uate those vibrations. The specification explains that dif-
  ferent characteristics of the liners are controlled
  corresponding to the structure of the propshaft. ’911 pa-
  tent at 7:56–8:43. It even provides a working example of
  tuned liners for use in a propshaft with specific dimensions
  and frequencies. Id. at 8:2–23. The claims include limita-
  tions which get progressively more detailed about the
  structure and positioning of the liner inside the drive shaft,
  none of which are addressed by the majority.
      AAM has at least raised factual questions about its as-
  serted inventive concepts which should have precluded
Case: 18-1763    Document: 134      Page: 55    Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS          23
  LLC


  summary judgment in this case. Rather than confront
  AAM’s actual claimed and argued unconventional ele-
  ments (such as a liner for attenuating bending mode vibra-
  tions), the majority creates its own strawman to knock
  down. The majority argues that AAM may have invented
  patentable refinements to sophisticated FEA software or
  computer modeling, but that they are not claimed. Maj. at
  13–14. Nowhere in the patent or the briefing does AAM
  claim that the ’911 patent’s improvement is FEA or com-
  puter modeling.
      The majority never addresses the inventive concepts
  alleged by AAM and listed in the above bullets points di-
  rectly from AAM’s opening brief. The second step of Al-
  ice/Mayo cannot be disregarded in the eligibility analysis.
                III. ENABLEMENT ON STEROIDS
      “A more accurate statement of the majority’s view
  would have been: ‘Section 101 can do everything 112 does-
  and then some.’” BIO Br. at 9. The majority’s new blended
  101/112 defense concerns the biotech and pharmaceutical
  industries who “expend great effort during patent prosecu-
  tion to meet the rigorous written description and enable-
  ment requirements.” BIO Br. at 7.
      Despite the fact that no party has argued that the
  claims are not enabled or that a skilled artisan would not
  know how to design a tuned liner and insert it into a given
  propshaft to reduce vibration, the majority nonetheless
  concludes the claims are ineligible because they don’t teach
  how to tune a liner. The majority’s concern is not preemp-
  tion of a natural law (which should be the focus), but rather
  that the claims do not teach a skilled artisan how to tune a
  liner without trial and error. The majority’s new blended
  101/112 defense is confusing, converts fact questions into
  legal ones and eliminates the knowledge of a skilled arti-
  san.
Case: 18-1763     Document: 134     Page: 56    Filed: 07/31/2020




  24     AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                      LLC


       According to the majority, even if the claims are ena-
  bled, they are still ineligible because the claims themselves
  didn’t teach how (the majority calls this the first how re-
  quirement). It is certainly correct that “[a]n improved re-
  sult, without more stated in the claim, is not enough to
  confer eligibility.” Koninklije KPN N.V. v. Gemalto M2M
  GmbH, 942 F.3d 1143, 1150 (Fed. Cir 2019); Elec. Power
  Grp., LLC v. Alstom S.A., 830 F.3d 1350, 1356 (Fed. Cir.
  2016) (claims are directed to an ineligible abstract idea
  when they “purport to monopolize every potential solution
  to the problem”). But such is not the case here. The goal
  or the result of the claimed invention is not a tuned liner;
  it is a drive shaft with reduced vibrations. Claims 1 and 22
  read:
       1. A method for manufacturing a shaft assembly of
       a driveline system, the driveline system further in-
       cluding a first driveline component and a second
       driveline component, the shaft assembly being
       adapted to transmit torque between the first
       driveline component and the second driveline com-
       ponent, the method comprising:
       providing a hollow shaft member;
       tuning at least one liner to attenuate at least two
       types of vibration transmitted through the shaft
       member; and
       positioning the at least one liner within the shaft
       member such that the at least one liner is config-
       ured to damp shell mode vibrations in the shaft
       member by an amount that is greater than or equal
       to about 2%, and the at least one liner is also con-
       figured to damp bending mode vibrations in the
       shaft member, the at least one liner being tuned to
       within about ±20% of a bending mode natural fre-
       quency of the shaft assembly as installed in the
       driveline system.
Case: 18-1763    Document: 134      Page: 57    Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS           25
  LLC


                           *    *   *
      22. A method for manufacturing a shaft assembly
      of a driveline system, the driveline system further
      including a first driveline component and a second
      driveline component, the shaft assembly being
      adapted to transmit torque between the first
      driveline component and the second driveline com-
      ponent, the method comprising:
      providing a hollow shaft member;
      tuning a mass and a stiffness of at least one liner,
      and
      inserting the at least one liner into the shaft mem-
      ber;
      wherein the at least one liner is a tuned resistive
      absorber for attenuating shell mode vibrations and
      wherein the at least one liner is a tuned reactive
      absorber for attenuating bending mode vibrations.
       The majority states the claim “must identify ‘how’ that
  functional result is achieved by limiting the claim scope to
  structures specified at some level of concreteness.” Maj. at
  27–28. It is clear from the claims themselves that the func-
  tional result is a drive shaft assembly with reduced vibra-
  tions. “The present invention relates to . . . a method for
  attenuating driveline vibrations transmitted through a
  shaft assembly.” ’911 patent at 1:4–7. It is undisputed that
  there exist many different ways to attenuate vibrations in
  a drive shaft such as dampers, plugs, weights, liners, even
  wadded up cardboard. The ’911 patent claims one specific
  way to attenuate vibrations, a concretely identified physi-
  cal structure—a liner inserted inside the propshaft. It does
  not just claim a result (reducing vibration)—it claims a spe-
  cific means of accomplishing the result—a liner positioned
  in the shaft. Even the amount of required reduction in vi-
  bration is an element in some claims (claim 1). Claim 22
  even specifies (as do others) that the liner is tuned to a
Case: 18-1763    Document: 134      Page: 58     Filed: 07/31/2020




  26    AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                     LLC


  given frequency by adjusting its mass and stiffness. And
  AAM alleges and the claims require that the liner’s place-
  ment inside the shaft aids in reducing vibration. There is
  no question the claims identify a concrete structure and
  even specify precise variables (mass and stiffness) to be ad-
  justed to tune the liner to the frequency of any given
  propshaft. The only remaining question (the majority’s
  true concern with these claims) is would a skilled artisan
  know how to adjust the mass, stiffness, and positioning of
  the liner in order to damp vibration without undue experi-
  mentation. See Oral Arg. at 12:04–11 (Judge) (“Basically
  it is done by trial-and-error. You start with a computer
  program and then you do trial and error to come to the cor-
  rect result, right?”); Oral Arg. at 29:20–36 (Judge) (“The
  claims themselves don’t even provide you with a list of var-
  iables, there are a lot of different variables, done by trial
  and error, and all the claims are telling you is here is a
  desirable result and use trial and error to get there.”). This
  is the question the majority has and this is a question of
  enablement, not eligibility.
      I dissent from the majority’s attempt to inject a height-
  ened enablement requirement into the § 101 analysis.
  These claims contain a specific, concrete solution (inserting
  a liner into a propshaft) to a problem (vibrations in a
  propshaft). Some degree of trial and error in modifying the
  mass and stiffness of the liner to optimize the reduction in
  vibration of a given shaft, could (if undue) create an ena-
  blement concern, but it is not a § 101 problem. And if § 101
  did require an analysis of whether too much trial and error
  would be required to reduce vibration of a given shaft at a
  particular frequency, surely this would be a question of fact
  and not something we decide for the first time on appeal.
                  IV. FUNDAMENTAL FAIRNESS
      I do not agree with the majority’s conclusion that
  claims 1 and 22 are representative or that AAM waived its
  arguments as to the dependent claims. First, Neapco never
Case: 18-1763     Document: 134      Page: 59     Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS             27
  LLC


  argued that claims 1 and 22 are representative and in fact
  argued the dependent claims separately. See Neapco SJ
  Br. at 32–33. Second, AAM expressly argued that they are
  not representative. Oral. Arg. 30:50–31:07. AAM’s state-
  ment that the dependent claims should not come out differ-
  ently does nothing more than confirm that it believes all of
  the claims are patent-eligible. Third, the majority inaccu-
  rately states AAM did not argue limitations of the depend-
  ent claims. AAM’s briefs provide multiple references to the
  type of material and other limitations found only in the de-
  pendent claims. See, e.g., AAM’s Opening Br. at 13–14, 36,
  57–58, and 64–65. I do not agree that AAM waived the
  dependent claims.
       As for claim 34 and 35 in particular, there is an even
  stronger basis for concluding that the majority is wrong. At
  six locations in the Opening Brief, AAM argues that loca-
  tion of the liners is one of its inventive control characteris-
  tics. Id. at 63 (“controlling its characteristics (e.g., length,
  width, interference fit, location, etc.)”); Id. at 64–65 (“The
  ’911 patent specifically teaches how to control the charac-
  teristics of a liner to not only match but damp relevant
  propshaft vibrations, including the thickness of the liner,
  the interference fit, the location of the liner”); Id. at 13
  (“The specification of the ’911 patent further explains that
  liners are tuned for damping by controlling ‘various char-
  acteristics’ including . . . location of the liners within the
  propshaft”); see also id. at 35–36 (same). “One liner char-
  acteristic that can be controlled—“location of the liners 204
  within the shaft member 200—is independent of its struc-
  ture, e.g., its mass and stiffness.” Id. at 42. And during
  oral argument, AAM explained that it did argue dependent
  limitations in the Opening Brief:
      “Q: I didn’t see in the Blue Brief separate argument
      about features of the dependent claims?
Case: 18-1763    Document: 134      Page: 60    Filed: 07/31/2020




  28     AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS
                                                      LLC


       A: We certainly talked about the location of the
       liner, that’s in our briefs, and talked about at
       length.”
  Oral Arg. at 30:50–31:01.
      Given that the majority now sua sponte holds that
  claim 22 does not contain a location limitation, it is unfair
  to refuse to review the dependent claims which unquestion-
  ably have detailed location limitations. Claim 34 states:
  “The method of claim 22, wherein a first one of the liners is
  positioned along the shaft member symmetrically about a
  bending anti-node.” Claim 35 further limits the location of
  a second liner placed in the shaft. Under these circum-
  stances, it is fundamentally unfair for the majority to hold
  that AAM did not present arguments regarding the de-
  pendent claim limitations in its Opening Brief. Finally,
  contrary to the majority’s assertion (Maj. at 24), the peti-
  tion for rehearing did not simply state that AAM did not
  waive arguments related to dependent claims. It pointed
  to three separate places in the Opening Brief (13–14, 57–
  59 and 64–65) where it expressly argued location of the
  liner. Given the Opening Brief’s repeated arguments about
  location and the majority’s nascent determination that
  claim 22 does not have a location limitation, it is wrong to
  hold AAM waived its arguments regarding dependent
  claims which contain location limitations.
                         CONCLUSION
      The majority holds that claims are directed to natural
  laws and are ineligible under § 101 if practicing the method
  would require application of a natural law and nothing
  more to achieve the claimed results, even when all of the
  technical experts disagree. The majority has concluded
  that the Nothing More question will be decided on appeal
  as a matter of law, without briefing and argument, and
  without regard to what the experts think. I cannot fathom
  the confusion that will be caused by declaring that claims
  are ineligible as directed to a natural law, when it is clear
Case: 18-1763    Document: 134      Page: 61     Filed: 07/31/2020




  AMERICAN AXLE & MANUFACTURING V. NEAPCO HOLDINGS           29
  LLC


  to all involved that this patent does not recite any particu-
  lar natural law. Every mechanical invention must apply
  the laws of physics—that does not render them all ineligi-
  ble, or maybe it does now. Section 101 simply should not
  be this sweeping and this manipulatable. And the major-
  ity’s collapse of the two-part Alice/Mayo test into a one-
  part test cannot stand. AAM has argued that there are un-
  conventional elements in these claims, such as using a
  liner to attenuate bending mode vibrations; this is not the
  natural law itself. The majority offers no explanation for
  why this patentee is not entitled to step two consideration,
  especially at this, the summary judgment stage.
       Our job, our mandate from Congress is to create a clear,
  uniform body of patent law. Our inability to do so in the
  § 101 space has not been a mess of our making. But, the
  unfairness, confusion and uncertainty that will be caused
  by this opinion is all us. Today, we make a choice. I dissent
  from this choice to extend the notions of ineligibility and to
  extend the role of the appellate court. Section 112 ade-
  quately protects for exactly the concerns the majority ex-
  presses, though honestly, I see no enablement problem and
  none was raised by the defendant. I dissent from the ma-
  jority’s chimeric approach to § 101 which is inconsistent
  with precedent, a vast expansion of § 101, and bound to
  cause confusion in future cases.
      I dissent from the conclusion that we judges are the
  true scientific experts. We should not be deciding technical
  questions, such as whether two types of vibration are re-
  duced by application of Hooke’s law and nothing more, as
  questions of law de novo on appeal.
