Court Opinion

ID: 4565548
Source: CourtListenerOpinion
Date Created: 2020-09-15 16:00:37.392939+00
Date Added: 2024-06-11T08:34:37.351928
License: Public Domain

Case: 19-2227    Document: 40    Page: 1   Filed: 09/15/2020

        NOTE: This disposition is nonprecedential.

   United States Court of Appeals
       for the Federal Circuit
                  ______________________

                      IQASR LLC,
                    Plaintiff-Appellant

                            v.

                     WENDT CORP.,
                    Defendant-Appellee
                  ______________________

                        2019-2227
                  ______________________

     Appeal from the United States District Court for the
 District of Colorado in No. 1:16-cv-01782-MSK-KMT, Sen-
 ior Judge Marcia S. Krieger.
                   ______________________

                Decided: September 15, 2020
                  ______________________

    RUDOLPH A. TELSCHER, JR., Husch Blackwell LLP, St.
 Louis, MO, for plaintiff-appellant. Also represented by
 KARA RENEE FUSSNER.

     ROBERT R. BRUNELLI, Sheridan Ross P.C., Denver, CO,
 for defendant-appellee. Also represented by KENDRIA
 ELIZABETH PEARSON.
                 ______________________

   Before DYK, CLEVENGER, and HUGHES, Circuit Judges.
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 2                                   IQASR LLC   v. WENDT CORP.

 HUGHES, Circuit Judge.
      This case concerns the validity of a patent for an auto-
 mobile scrap recycling process. IQASR LLC appeals the
 district court’s decision holding U.S. Patent No. 9,132,432
 invalid for indefiniteness. IQASR argues that the district
 court erred in its application of the legal standard for in-
 definiteness and in its findings on both the intrinsic and
 extrinsic evidence. Because the district court did not err in
 its legal analysis or its factfinding, we affirm.
                               I
     The ’432 patent teaches various methods to sort recy-
 clable materials from non-recyclable materials in “automo-
 bile shredder residue.” This term refers to the residue
 produced by shredding “end-of-life” vehicles, i.e.,
 “scrapped” or “junked” automobiles, for disposal and recy-
 cling. The ’432 patent’s claimed methods aim to enhance
 the separation of non-recyclable materials like “trash and
 magnetic fuzz” from recyclable materials like “plastics and
 metals,” allowing recovery of more recyclable materials.
 See, e.g., ’432 patent at 1:48–50, 2:1–15.
      The claim terms whose definiteness is disputed in this
 appeal, “magnetic fuzz,” and “low susceptance microparti-
 cles” are found in independent claim 1 and dependent
 claim 13, reproduced below with the relevant terms itali-
 cized.
         1. A method of separation of automobile shred-
     der residue comprising the steps of:
     providing automobile shredder residue as a result
            from a ferrous sorting recovery system;
     introducing said automobile shredder residue into
            an auto mobile shredder residue sorting,
            non-ferrous recovery system;
     non-magnetically sorting magnetic fuzz from said
           automobile shredder residue with said
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 IQASR LLC   v. WENDT CORP.                                   3

               automobile shredder residue sorting, non-
               ferrous recovery system;
     wherein said sorted magnetic fuzz is substantially
            free of recyclable materials.
         13. A method of separation of automobile
     shredder residue according to claim 1 wherein said
     step of non-magnetically sorting magnetic fuzz
     from said automobile shredder residue with said
     automobile shredder residue sorting, non-ferrous
     recovery system comprises the step of non-mag-
     netically sorting separating [sic] low susceptance
     microparticles from said automobile shredder resi-
     due with said automobile shredder residue sorting,
     non-ferrous recovery system.
 ’432 patent at 23:7–18, 24:16–23.
                               II
      IQASR sued Wendt Corp. for infringement of the ’432
 patent. See IQASR LLC v. Wendt Corp., No. 16-CV-01782-
 MSK-KMT, 2019 WL 1075477 (D. Colo. Mar. 7, 2019) (De-
 cision). After a Markman hearing, the district court held
 the ’432 patent invalid under 35 U.S.C. § 112. See id. The
 parties disputed six claim terms. Id. at *2–3. In constru-
 ing these terms, the court found “magnetic fuzz” indefinite,
 rendering independent claim 1 (and thus the remaining
 claims, all dependent from claim 1) indefinite. Id. at *6–8.
 It also found “low susceptance microparticles” in dependent
 claim 13 indefinite. Id. at *9.
     IQASR appeals the district court’s final judgment in-
 validating all claims of the ’432 patent based on these two
 terms’ indefiniteness. IQASR having timely appealed, we
 have jurisdiction under 28 U.S.C. § 1295(a)(1).
     “[W]e review a district court’s determination that a
 claim is invalid as indefinite . . . de novo, although, as with
 claim construction, any factual findings by the district
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 4                                   IQASR LLC   v. WENDT CORP.

 court based on extrinsic evidence are reviewed for clear er-
 ror.”     Sonix Tech. Co. v. Publications Int’l, Ltd.,
 844 F.3d 1370, 1376 (Fed. Cir. 2017). “To trigger clear er-
 ror review, ‘it is not enough that the district court may have
 heard extrinsic evidence during a claim construction pro-
 ceeding—rather, the district court must have actually
 made a factual finding.’” Id. (quoting CardSoft, LLC v. Ver-
 iFone, Inc., 807 F.3d 1346, 1350 (Fed. Cir. 2015)). “Moreo-
 ver, ‘[a] party cannot transform into a factual matter the
 internal coherence and context assessment of the patent
 simply by having an expert offer an opinion on it. The in-
 ternal coherence and context assessment of the patent, and
 whether it conveys claim meaning with reasonable cer-
 tainty, are questions of law.’” Id. (quoting Teva Pharm.
 USA, Inc. v. Sandoz, Inc., 789 F.3d 1335, 1342 (Fed. Cir.
 2015)).
                              III
      IQASR asserts that the district court erred on three
 fronts. First, IQASR argues that the district court commit-
 ted multiple legal errors in applying the law of indefinite-
 ness. These assertions of legal error leak into IQASR’s
 second and third arguments: that the district court erred
 in its findings of fact from both the extrinsic evidence prof-
 fered and the intrinsic record. We reject each of these ar-
 guments because the district court appropriately analyzed
 the definiteness of the ’432 patent and did not reversibly
 err in its factfinding. As a result, we affirm the district
 court’s conclusion that, as used in the ’432 patent, “mag-
 netic fuzz” is indefinite. 1

     1   Since we affirm the indefiniteness of “magnetic
 fuzz,” used in independent claim 1, we need not decide the
 definiteness of “low susceptance microparticles.” The lat-
 ter term appears only in claim 13, which depends from
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 IQASR LLC   v. WENDT CORP.                                    5

      We address IQASR’s assertions of error regarding the
 extrinsic evidence and then its assertions regarding the in-
 trinsic evidence, interspersing its assertions of legal error
 where relevant to the district court’s analysis of its findings
 of fact.
                                A
      “In the face of an allegation of indefiniteness, general
 principles of claim construction apply.” Biosig Instru-
 ments, Inc. v. Nautilus, Inc., 783 F.3d 1374, 1377–78
 (Fed. Cir. 2015) (quoting Enzo Biochem, Inc. v. Applera
 Corp., 599 F.3d 1325, 1332 (Fed. Cir. 2010)). “The inquiry
 into how a person of ordinary skill in the art understands
 a claim term provides an objective baseline from which to
 begin claim interpretation.” Phillips v. AWH Corp., 415
F.3d 1303, 1313 (Fed. Cir. 2005). “[T]he ordinary and cus-
 tomary meaning of a claim term is the meaning that the
 term would have to a person of ordinary skill in the art in
 question at the time of the invention, i.e., as of the effective
 filing date of the patent application.” Id.
      We do not perceive any clear error in the district court’s
 finding that “magnetic fuzz” lacks “a readily-understood
 definition in [its] field.” 2 Decision at *7. “A factual finding
 is clearly erroneous if, despite some supporting evidence,

 claim 1, so our disposition of “magnetic fuzz” renders su-
 perfluous the dispute over claim 13’s validity.
     2      The scope of the relevant “field” is unclear. On ap-
 peal, IQASR asserts that “[i]f ‘magnetic fuzz’ is a term of
 art . . . it is a term from the automobile recycling industry.
 A person with no experience in that field cannot compe-
 tently testify as to whether the term was known and used.”
 Reply Br. 16. But this contradicts IQASR’s experts, both of
 whom defined the relevant skilled artisan to include per-
 sons with no direct experience in the automotive recycling
 industry. See J.A. 1236–37; J.A. 1578.
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 6                                    IQASR LLC   v. WENDT CORP.

 we are left with the definite and firm conviction that a mis-
 take has been made.” Stone Basket Innovations, LLC v.
 Cook Med. LLC, 892 F.3d 1175, 1178 (Fed. Cir. 2018) (quot-
 ing Rothschild Connected Devices Innovations, LLC v.
 Guardian Prot. Servs., Inc., 858 F.3d 1383, 1387 (Fed. Cir.
 2017)). The district court reviewed evidence from experts
 on both sides. Although it did not cite the evidence from
 Wendt’s expert, “failure to mention [evidence] does not
 mean failure to consider [that evidence] when the evidence
 supplies support for the district court’s determination.”
 FMC Corp. v. Hennessy Indus., 836 F.2d 521, 524 (Fed. Cir.
 1987). The testimony of Wendt’s expert supported the dis-
 trict court’s determination. See, e.g., J.A. 1734–40. The
 district court could properly rely on that testimony to es-
 tablish that “magnetic fuzz” had no ordinary meaning.
 Aventis Pharma S.A. v. Hospira, Inc., 675 F.3d 1324, 1331
 (Fed. Cir. 2012) (“A district court . . . has the discretion to
 take expert testimony into account in determining the or-
 dinary meaning of a claim term to one skilled in the art.”).
     Although IQASR argues that the expert’s testimony
 should be discounted because of his lack of direct experi-
 ence in automobile recycling, the district court was entitled
 to weigh the expert’s testimony as it thought appropriate
 based on the expert’s qualifications and experience. “De-
 termining the weight and credibility of the evidence is the
 special province of the trier of fact.” Inwood Labs., Inc. v.
 Ives Labs., Inc., 456 U.S. 844, 856 (1982); see also Teva
 Pharm. USA, Inc. v. Sandoz, Inc., 574 U.S. 318, 326–27
 (2015) (“[I]n patent construction, subsidiary factfinding is
 sometimes necessary. . . . [S]ometimes courts may have to
 make ‘credibility judgments’ about witnesses . . . [and] may
 have to resolve subsidiary factual disputes.” (quoting
 Markman v. Westview Instruments, Inc., 517 U.S. 370, 389
 (1996))).
     Finally, that IQASR’s experts provided testimony con-
 tradicting Wendt’s expert does not foreclose the district
 court from finding Wendt’s expert’s testimony clear and
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 IQASR LLC   v. WENDT CORP.                                 7

 convincing evidence that “magnetic fuzz” has no ordinary
 meaning. See Intel Corp. v. U.S. Int’l Trade Comm’n, 946
F.2d 821, 830 (Fed. Cir. 1991) (“Clear and convincing evi-
 dence has been described as evidence which proves in the
 mind of the trier of fact ‘an abiding conviction that the
 truth of [the] factual contentions are [sic] “highly proba-
 ble.”’” (quoting Colorado v. New Mexico, 467 U.S. 310, 316
 (1984))).
      We see no clear error in the district court’s conclusion
 that IQASR’s evidence about the existence of an ordinary
 meaning of “magnetic fuzz” failed to rebut Wendt’s evi-
 dence about the absence of an ordinary meaning. The dis-
 trict court could reasonably discount the importance of the
 more extensive use of the term “fuzz” prior to the invention
 date or the isolated use of the term “magnetic fuzz” in re-
 lated, but different recycling contexts. Decision at *7.
 These usages may have given a skilled artisan some con-
 text for the meaning of “magnetic fuzz” in the ’432 patent,
 but IQASR does not establish that these alone could resolve
 “questions of precision as to the[] boundaries” of magnetic
 fuzz. Frans Nooren Afdichtingssystemen B.V. v. Stopaq
 Amcorr Inc., 744 F.3d 715, 725 (Fed. Cir. 2014).
     Likewise, the district court was entitled to give no
 weight to the evidence that, in IQASR’s view, shows there
 was an ordinary and customary meaning of “magnetic fuzz”
 known in the art. IQASR points to (1) an email exchange
 between an associate of the inventor and Wendt’s engineer
 where the associate used the term “magnetic fuzz,” and
 Wendt’s engineer responded without expressing confusion
 about the term, J.A. 1825, and (2) the inventor’s question
 to a panelist at the Institute of Scrap Recycling Industries
 conference, in which the inventor used the term “magnetic
 fuzz” among a host of related terms, and the panelist an-
 swered the question without showing confusion about the
 term. J.A. 1840–43.
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 8                                   IQASR LLC   v. WENDT CORP.

      But these events took place after the issuance of the
 patent, see J.A. 59, 278–81, limiting their value in estab-
 lishing the meaning of the term at the time of invention,
 some five years earlier. See Brookhill-Wilk 1, LLC. v. Intu-
 itive Surgical, Inc., 334 F.3d 1294, 1299 (Fed. Cir. 2003)
 (refusing to consider documents published after the grant
 of a patent in construing the patent’s claims because the
 documents were “not contemporaneous with the patent,
 [and] do not reflect the meanings that would have been at-
 tributed to the words in dispute by persons of ordinary skill
 in the art as of the grant of [the] patent”). Even if the tim-
 ing of these events did not undermine their evidentiary
 value, the district court could have reasonably found these
 events unhelpful in establishing that an artisan would un-
 derstand the meaning “magnetic fuzz” with reasonable cer-
 tainty, and discounted this evidence. See Decision at *7.
     And, as the trier of fact, in neither of these circum-
 stances did the district court err by drawing inferences
 against IQASR from IQASR’s own evidence. Thanks to the
 presumption of validity, “the patent challenger bears the
 burden of proving the factual elements of invalidity by
 clear and convincing evidence.” Pfizer, Inc. v. Apotex, Inc.,
 480 F.3d 1348, 1359 (Fed. Cir. 2007). But the patent chal-
 lenger’s standard of proof does not impose limitations on
 the factfinder’s ability to draw reasonable inferences from
 the evidence presented.
     Altogether, IQASR’s arguments do not leave us with a
 definite and firm conviction that the district court clearly
 erred in finding that “magnetic fuzz” lacked an ordinary
 and customary meaning in the art at the time of the inven-
 tion.
                               B
     The district court’s focus on whether the intrinsic rec-
 ord adequately prescribes the meaning of “magnetic fuzz”
 was also proper. Because indefiniteness applies “general
 principles of claim construction,” indefiniteness “involves
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 IQASR LLC   v. WENDT CORP.                                     9

 consideration of primarily the intrinsic evidence, viz., the
 claim language, the specification, and the prosecution his-
 tory.” Biosig, 783 F.3d at 1377–78 (quoting Enzo, 599 F.3d
 at 1332). The importance of the intrinsic evidence reaches
 its zenith in cases like this when the district court finds
 from the extrinsic evidence that the term lacks an ordinary
 meaning. When a term “has no ordinary and customary
 meaning,” it is a “coined term,” raising the question of
 “whether the intrinsic evidence provides objective bounda-
 ries to the scope of the term.” Iridescent Networks, Inc. v.
 AT&T Mobility, LLC, 933 F.3d 1345, 1353 (Fed. Cir. 2019)
 (citing Interval Licensing LLC v. AOL, Inc., 766 F.3d 1364,
 1371 (Fed. Cir. 2014) (“The claims, when read in light of
 the specification and the prosecution history, must provide
 objective boundaries for those of skill in the art.”)). “The
 failure to define [a] term is . . . not fatal, for if the meaning
 of the term is fairly inferable from the patent, an express
 definition is not necessary.” Bancorp Servs., L.L.C. v. Hart-
 ford Life Ins. Co., 359 F.3d 1367, 1373 (Fed. Cir. 2004).
      Reviewing the intrinsic record, we agree with the dis-
 trict court that the ’432 “patent fails to offer any meaning-
 ful and functional explanation” of the definitional
 characteristics of “magnetic fuzz,” leaving “the nature of
 that substance . . . decidedly unclear.” Decision at *7. In
 other words, the ’432 patent neither defines “magnetic
 fuzz,” nor provides enough explanation that an artisan may
 infer reasonably certain, objective boundaries of the term.
 See Biosig, 783 F.3d at 1380–81.
     IQASR argues that the ’432 patent defines “magnetic
 fuzz” as a light, unrecyclable component of automobile
 shredder residue, that is a type of magnetic “low suscep-
 tance microparticle” and also “magnetically active disasso-
 ciated microparticles,” that would clog a non-ferrous
 recovery system. Appellant’s Br. 39–43. The specification
 supports these statements—but it also clouds them. For
 example, “low susceptance microparticles could be mag-
 netic fuzz, iron oxide particles, microparticles, dust, trash,
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 10                                  IQASR LLC   v. WENDT CORP.

 ferromagnetic particles, non- or even anti-ferromagnetic
 particles or the like and may even be small perhaps less
 than about one inch in size or the like.” ’432 patent
 at 6:7–11. So magnetic fuzz is not the only type of low sus-
 ceptance microparticle. 3 “Low susceptance microparticles
 may be magnetically active disassociated particles with
 low or magnetic or perhaps even low sensor susceptibility,
 such s [sic] but not limited to magnetic fuzz.” Id. at 6:18–
 21. So magnetic fuzz is a type of low susceptance micro-
 particle that is a magnetically active disassociated micro-
 particle—but not the only type of magnetically active
 disassociated microparticle. How is one to know, then,
 whether a magnetically active disassociated particle is
 magnetic fuzz? The patent explains only that “[d]isassoci-
 ated magnetically active microparticles may be magnetic
 fuzz because these particles may be difficult to substan-
 tially identify.” Id. at 6:27–29. The equivocation and sub-
 jectivity displayed in this statement present obstacles to
 understanding no matter the reader’s technical back-
 ground.

      3   In fact, magnetic fuzz may be distinct from low sus-
 ceptance microparticles; the ’432 patent describes using a
 magnet to remove “low susceptance microparticles or mag-
 netic fuzz or the like.” ’432 patent at 6:41–42; see also id.
 at 13:31–38 (“The collection of materials (9) may include,
 but is not limited to, recyclable materials, sorted materials,
 a collection of low susceptance microparticles, a salable
 output, a salable concentration output of end product
 waste, a collection of magnetic fuzz, a collection of substan-
 tially isotropic quantized materials, a trash output, sorted
 landfill substances, additional processing substances, or
 the like.”).
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 IQASR LLC   v. WENDT CORP.                                 11

      Ultimately, to discern “magnetic fuzz,” an artisan has
 to find the low susceptance microparticles, 4 and then iden-
 tify which low susceptance microparticles are disassociated
 magnetically active microparticles. Because the multiple
 layers of definitions are all open-ended and non-limiting, 5
 a skilled artisan must wade through a morass of uncer-
 tainty and contradiction to get to this point. It is this word
 salad of inconsistent indirect definitions and examples that
 so flummoxed the district court. We agree with the district
 court that “[t]he lack of a meaningful description of what
 constitutes magnetic fuzz prevents a person skilled in the

     4    “Low susceptance microparticles” are themselves
 described capriciously enough that the district court held
 the term indefinite. See Decision at *9. We need not rely
 on this conclusion in our analysis of magnetic fuzz, how-
 ever.
      5   “Low susceptance microparticles may have low
 magnetic sensor susceptibility, may be small magnetic par-
 ticles in size, or may even be non-magnetic or the like.”
 ’432 patent at 6:14–16. So low susceptance particles might
 have low magnetic sensor susceptibility. But maybe not?
 They might be small magnetic particles—but they might
 not be magnetic at all. They “may even be small perhaps
 less than about one inch in size or the like.” Id. at 6:10–11.
 But the specification does not foreclose the possibility that
 they are not. Without better guidance, an artisan must
 speculate which choice of the alternative characteristics
 better describes any of these terms in a given situation. Cf.
 Interval Licensing, 766 F.3d at 1373–74 (“Had the phrase
 been cast as a definition instead of as an example—if the
 phrase had been preceded by ‘i.e.’ instead of ‘e.g.’—then it
 would help provide the clarity that the specification lacks.
 But as the specification is written, we agree with the dis-
 trict court that a person of ordinary skill in the art would
 not understand the ‘e.g.’ phrase to constitute an exclusive
 definition.”).
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 12                                   IQASR LLC   v. WENDT CORP.

 art from knowing when it is present and how to address it.”
 Decision at *7. A technical degree or industry experience
 does not confer the ability to transcend patent ambiguity.
     IQASR argues that the district court erred by recogniz-
 ing the uncertainty in the specification’s habitual use of
 “may” to define and describe these terms, professing that
 the district court improperly disregarded these definitions
 based on this usage pattern. IQASR is correct that the use
 of “modal verbs” to give non-limiting examples for a claim
 term does not necessarily render that term indefinite. But,
 such non-limiting examples do not on their own expressly
 define the bounds—the limits—of the claim. Cf. Am. Med.
 Sys., Inc. v. Biolitec, Inc., 618 F.3d 1354, 1361 (Fed. Cir.
 2010) (finding that “the use of the words ‘based upon,’ ra-
 ther than ‘means’ or ‘is,’” to describe a term used in a claim
 preamble undermined the patentee’s argument that the de-
 scription of the term was intended to be “used as a defini-
 tion” of the term). A patentee cannot simultaneously use
 non-modal verbs to avoid limiting the scope of an invention
 while also arguing that those same examples define the
 limits of the invention. And this is especially true when
 the non-limiting examples include both possibilities of a bi-
 nary property (i.e., that low susceptance microparticles
 may be magnetic—but also, may not be).
     In some cases, non-limiting examples provide sufficient
 information to allow a skilled artisan to infer the bounds of
 a term or to eradicate any latent ambiguity in a term. In-
 terval Licensing, 766 F.3d at 1373 (“We recognize that a
 patent which defines a claim phrase through examples may
 satisfy the definiteness requirement.”). But in other cases,
 contradictory examples in the specification introduce am-
 biguity to an otherwise clear term and render it indefinite.
 “[C]laims which on first reading . . . appear indefinite may
 upon a reading of the specification disclosure or prior art
 teachings become quite definite. . . . [But] this rule also ap-
 plies in the reverse, making an otherwise definite claim
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 IQASR LLC   v. WENDT CORP.                                  13

 take on an unreasonable degree of uncertainty.” Applica-
 tion of Moore, 439 F.2d 1232, 1235 n.2 (CCPA 1971).
     This is not a case where the specification “provides ‘a
 general guideline and examples sufficient to enable a per-
 son of ordinary skill in the art to determine [the scope of
 the claims] . . . .’” Enzo, 599 F.3d at 1335 (alteration in
 original) (quoting In re Marosi, 710 F.2d 799, 803 (Fed. Cir.
 1983)). Open-ended definition of categories that might or
 might not possess certain traits cannot provide reasonably
 certain bounds on the scope of “magnetic fuzz.” The num-
 ber of times “magnetic fuzz” is referenced in the specifica-
 tion is inapposite. Additional discussion of a concept may
 obfuscate the concept just as much as it may clarify it. We
 see no error in the district court’s holding that the intrinsic
 record lacks the “meaningful and functional explanation of
 th[e] characteristics” of “magnetic fuzz” needed to provide
 reasonably certain bounds of the scope of the term. Deci-
 sion at *7.
      We further note that even if an artisan were to pierce
 the fog of microparticle definitions, the chief definitional
 characteristic of magnetic fuzz remains that it is “difficult
 to substantially identify.” ’432 patent at 6:29. This is a
 subjective definition, with no further explanation of how to
 decide when particles are “difficult to substantially iden-
 tify.” Merely defining magnetic fuzz as the subset of disas-
 sociated magnetically active microparticles that are
 “difficult to substantially identify” “leave[s] the skilled ar-
 tisan to consult the ‘unpredictable vagaries of any one per-
 son’s opinion.’” Dow Chem. Co. v. Nova Chems. Corp.
 (Canada), 803 F.3d 620, 635 (Fed. Cir. 2015) (quoting In-
 terval Licensing, 766 F.3d at 1374). Since the patent pro-
 vides no explanation of what makes a particle “difficult to
 substantially identify,” resolving whether particles are
 “difficult to substantially identify” requires reliance on sub-
 jective opinion alone. Whether an object is difficult to iden-
 tify will always depend on an artisan’s own perception of
 difficulty and an uncertain concept of identity that varies
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 14                                  IQASR LLC   v. WENDT CORP.

 depending on the level of detail sought. And on top of this,
 the inherent uncertainty in the patent’s definition of low
 susceptance microparticles and magnetically active disas-
 sociated microparticles further undermines the definite-
 ness of “magnetic fuzz.”
                               C
     We reject IQASR’s assertions that the district court
 must have applied an impermissibly strict standard of def-
 initeness or neglected the perspective of a skilled artisan to
 come to this conclusion. 6 IQASR argues that magnetic fuzz
 is definite because “the skilled artisan would presumably
 be familiar with what clogged the non-ferrous recovery sys-
 tem and would thereby recognize magnetic fuzz.” Appel-
 lant’s Br. 43 (emphasis omitted). But this asserts a
 subjective view of the claims that improperly allows “the
 scope [to] vary from day-to-day and from person-to-person,”
 providing “a moving target that may change over time.”
 Icon Health & Fitness, Inc. v. Polar Electro Oy, 656 F. App’x
 1008, 1016 (Fed. Cir. 2016). The problem raised by this
 subjectivity is not the “fact that the composition varies
 from process-to-process.” Appellant’s Br. 47. It is that the
 “lack of a meaningful description of what constitutes mag-
 netic fuzz prevents a person skilled in the art from knowing

      6  Nor does the failure to cite any particular legal
 standard compel the conclusion that the district court ig-
 nored that standard. “The court is presumed to have ap-
 plied the law correctly, absent a clear showing to the
 contrary.” Lee v. Dayton-Hudson Corp., 838 F.2d 1186,
 1189 (Fed. Cir. 1988). “When determining whether a court
 committed legal error in selecting the appropriate legal
 standard, we determine which legal standard the tribunal
 applied . . . .” James v. Wilkie, 917 F.3d 1368, 1373–74
 (Fed. Cir. 2019) (emphasis in original). For the reasons ex-
 plained within, we remain unpersuaded that the district
 court applied incorrect legal standards.
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 IQASR LLC   v. WENDT CORP.                                  15

 when” a composition produced by a particular process–or
 clogging the non-ferrous recovery system–is or is not mag-
 netic fuzz. Decision at *7.
      Furthermore, a claim term does not become reasonably
 certain simply because a skilled artisan, when pressed,
 managed to articulate a definition for it. “Even if a claim
 term’s definition can be reduced to words, the claim is still
 indefinite if a person of ordinary skill in the art cannot
 translate the definition into meaningfully precise claim
 scope.” Halliburton Energy Servs., Inc. v. M-I LLC, 514
F.3d 1244, 1251 (Fed. Cir. 2008). For this reason, Wendt
 did not have to “prove by clear and convincing evidence
 that the claim term was not understood amongst the indus-
 try” as IQASR suggests. Appellant’s Br. 48. It had to
 prove that “magnetic fuzz,” “when read in light of the spec-
 ification and the prosecution history, ‘fail[s] to inform, with
 reasonable certainty, those skilled in the art about the
 scope of the invention.’” Interval Licensing, 766 F.3d
 at 1369–70 (quoting Nautilus, Inc. v. Biosig Instruments,
 Inc., 572 U.S. 898, 901 (2014)). Showing that a skilled ar-
 tisan cannot recognize the scope of a claim term with rea-
 sonable certainty requires showing considerably less
 uncertainty than showing that a skilled artisan could not
 understand the claim term. The latter is closer to the “in-
 solubly ambiguous” standard rejected by Nautilus. See
 Nautilus, 572 U.S. at 911 (“It cannot be sufficient that a
 court can ascribe some meaning to a patent’s claims . . . .”).
                               IV
      We have considered the parties’ other arguments and
 find them unpersuasive. Because the district court appro-
 priately scrutinized the intrinsic and extrinsic evidence
 and suitably applied the law of indefiniteness, we affirm
 the district court’s judgment holding the ’432 patent inva-
 lid for indefiniteness.
                         AFFIRMED