Case: 24-1466 Document: 58 Page: 1 Filed: 11/12/2025

United States Court of Appeals for the Federal Circuit ______________________

CANATEX COMPLETION SOLUTIONS, INC., Plaintiff-Appellant

v.

WELLMATICS, LLC, GR ENERGY SERVICES, LLC, GR ENERGY SERVICES MANAGEMENT, LP, GR ENERGY SERVICES OPERATING GP, LLC, GR WIRELINE, L.P., Defendants-Appellees ______________________

2024-1466 ______________________

Appeal from the United States District Court for the Southern District of Texas in No. 4:22-cv-03306, Judge Al- fred H. Bennett. ______________________

Decided: November 12, 2025 ______________________

J. DAVID CABELLO, Cabello Hall Zinda PLLC, Houston, TX, argued for plaintiff-appellant. Also represented by STEPHEN D. ZINDA.

PHILLIP AURENTZ, Sidley Austin LLP, Dallas, TX, ar- gued for defendants-appellees. Also represented by MORGAN R. MENDICINO; JOSHUA JOHN FOUGERE, Washing- ton, DC. ______________________ Case: 24-1466 Document: 58 Page: 2 Filed: 11/12/2025

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Before MOORE, Chief Judge, PROST and TARANTO, Circuit Judges. TARANTO, Circuit Judge. Canatex Completion Solutions, Inc. owns U.S. Patent No. 10,794,122, titled “Releasable Connection for a Down- hole Tool String,” which claims a device, having two parts, that is used in oil and gas wells. When the device operator intends to leave the lower (further downhole) part of the device in the drilled hole, perhaps because the downhole part has gotten stuck, the operator can disconnect the two parts of the device, leaving the first part in the well while pulling the second part toward or to the surface. Canatex sued Wellmatics, LLC; GR Energy Services, LLC; GR En- ergy Services Management, LP; GR Energy Services Oper- ating GP, LLC; and GR Wireline, L.P. (collectively, defendants) in September 2022 in the U.S. District Court for the Southern District of Texas, alleging infringement of the ’122 patent. Defendants challenged the ’122 patent’s validity, argu- ing that asserted claims 1, 4–13, and 15–19 are indefinite for lack of an antecedent basis for the phrase now at issue, “the connection profile of the second part,” which appears in all the independent claims (1, 7, and 13). Canatex ar- gued that the phrase contains what a relevant artisan would recognize to be an evident error with an evident sim- ple correction, i.e., that a relevant artisan would clearly un- derstand the intended meaning to be “the connection profile of the first part.” The same asserted error appears once in the patent’s Abstract and twice in the patent’s writ- ten description. ’122 patent, Abstract; id., col. 1, lines 33– 34; col. 3, lines 31–32. Canatex asked the district court to construe the phrase to reflect the asserted correction of “second” to “first.” The district court rejected Canatex’s argument and agreed with defendants that claims 1, 7, and 13 are invalid Case: 24-1466 Document: 58 Page: 3 Filed: 11/12/2025

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for indefiniteness. See Canatex Completion Solutions, Inc. v. Wellmatics, LLC, No. 4:22-CV-03306, 2023 WL 9645474, at *2–3 (S.D. Tex. Dec. 14, 2023) (Claim Construction Or- der). The district court ruled that “the error” identified by Canatex “is not evident from the face of the patent and the correction to the claim is not as simple as [Canatex] makes it seem.” Id. at *3. We now reverse, concluding that it is evident that the claim contains an error and that a relevant artisan would recognize that there is only one correction that is reasonable given the intrinsic evidence. I A Canatex’s ’122 patent, which issued in October 2020, claims and discloses a “releasable connection” tool used in operations in oil and gas wells. ’122 patent, Abstract. The device comprises two “parts,” which are locked together during normal downhole operations but can be separated by action from the operator on the ground. ’122 patent, col. 1, lines 12–20. The “first part” is the part further downhole (distal), and the “second part” is the part closer to the land surface (proximal). If circumstances warrant, e.g., if the first part becomes stuck due to debris lodged in the well- bore, the two parts of the device can be disconnected from each other, allowing the second part to be retrieved imme- diately while the first part remains downhole for later re- trieval. ’122 patent, col. 1, lines 12–20; id., col. 3, lines 1– 24; J.A. 1276. Independent claim 1 of the ’122 patent is representa- tive of the claims at issue for present purposes. With em- phases added to highlight the mechanics relevant to the issue before us, and internal clause labels ([a]–[b], [i]–[v]) added for ease of reference, the claim reads as follows: 1. A releasable connection for a downhole tool string, comprising Case: 24-1466 Document: 58 Page: 4 Filed: 11/12/2025

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[a] a first part comprising an external connec- tion profile; and [b] a second part comprising: [i] an outer housing; [ii] a releasable engagement profile which internally engages the connection profile of the first part and which is configured to expand radially to release the connection profile of the first part; [iii] a locking piston positioned within an internal cavity of the second part, the lock- ing piston configured to move axially along the second part between a locking position that directly constrains the releasable en- gagement profile into engagement with the connection profile of the first part and a release position that permits the releas- able engagement profile to expand radi- ally to release the connection profile of the second part; [iv] an expansion chamber in fluid communica- tion with the locking piston; and [v] a source of fluid pressure in communication with the expansion chamber, wherein, upon ac- tivation, the source of fluid pressure is config- ured to apply fluid pressure to move the locking piston from the locking position toward the re- lease position. ’122 patent, col. 5, lines 16–40 (emphases added). The underlined phrase is the phrase specifically at is- sue here. That language appears in each of independent claims 1, 7, and 13, once in the abstract, and twice in the written description. ’122 patent, Abstract; id., col. 1, lines 33–34; col. 3, lines 31–32. The issue before us is whether Case: 24-1466 Document: 58 Page: 5 Filed: 11/12/2025

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it is sufficiently clear that “second” in the underlined phrase must mean (and thus be corrected to) “first.” With that one change, the claim logically and clearly lays out the following structure. Clauses [a] and [b] call for a first part that connects with a second part. Clause [b][ii] says that the first part’s connection component is a connec- tion profile, which engages—releasably and in the inside of—a component of the second part (releasable engagement profile), and the second part’s engagement profile can “ex- pand radially to release the connection profile of the first part.” Clause [b][iii] then specifies how the engagement and release are effectuated—by a “locking piston” that moves between two different positions. In a “locking posi- tion,” the piston “directly constrains the releasable engage- ment profile into engagement with the connection profile of the first part”; in a “release position,” the piston “permits the releasable engagement profile to expand radially to re- lease the connection profile of the [first, replacing ‘second’] part.” Clauses [b][iv]–[v] then specify how the locking pis- ton moves—by activated fluid pressure reaching the piston in an expansion chamber—“from the locking position to- ward the release position.” The two figures from the patent displayed after the pre- sent paragraph illustrate the device claimed. Figure 1 shows the first and second part separated. Figure 2 shows the two parts when connected, and Figure 3 shows a blowup of the connection area in Figure 2. We display Fig- ures 1 and 3. To those figures we have added word labels, drawn from the specification, for the items of principal sig- nificance to the dispute before us. We have also added the directional guide, with labels, at the top of the figures. Case: 24-1466 Document: 58 Page: 6 Filed: 11/12/2025

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B On September 27, 2022, Canatex sued defendants, al- leging infringement of claims 1, 4–13, and 15–19 of the ’122 patent, and one day later Canatex moved for a preliminary injunction. J.A. 24–25, 88. The district court denied the motion for preliminary injunction, and the case proceeded to claim construction. J.A. 1159. In their claim-construc- tion brief, defendants argued that all asserted claims are indefinite because the language “the connection profile of the second part” in clause [b][iii], with “the” at its begin- ning, needs but lacks an antecedent basis earlier in the claim. J.A. 1633. Specifically, as is evident in the quoted claim language above, claim 1 introduces a “first part comprising an external connection profile” (clause [a]) but does not mention any connection profile of the second part until the backward-referring mention of “the connection profile of the second part” in clause [b][iii]. We have been pointed to no place prior to defendants’ filing on claim con- struction at which the parties (or the Examiner during prosecution) adverted to any uncertainty regarding the meaning of this claim language or its potential indefinite- ness. See J.A. 1389 (Canatex’s Opening Claim Construc- tion Brief); J.A. 872–73 (Indefiniteness Rejection on Other Grounds). In response, Canatex agreed that a required anteced- ent basis was missing, but it contended that the language problem—an evident error with an evident correction—had a simple solution. It argued that “the nature of the error and its correction are remarkably apparent,” as a relevant artisan would immediately understand the claim to refer to the connection profile of the first part, the only connec- tion profile previously mentioned in the claim and the only connection profile reasonably understood to exist from the patent as a whole. J.A. 1795–800; J.A. 1390. Relying on our precedents authorizing courts to interpret patent claims to correct claim-language errors in very narrow cir- cumstances, Canatex argued that the reference to the Case: 24-1466 Document: 58 Page: 8 Filed: 11/12/2025

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“connection profile of the second part” should be construed to mean “the connection profile of the second first part.” J.A. 1389; J.A. 1794–95; see Ultimax Cement Manufactur- ing Corp. v. CTS Cement Manufacturing Corp., 587 F.3d 1339, 1353 (Fed. Cir. 2009)). On December 14, 2023, the district court held all as- serted claims to be invalid for indefiniteness because the claim phrase at issue needed but lacked an antecedent ba- sis. Claim Construction Order, at *2–4. The district court disagreed with Canatex’s contention that the claims con- tained a “clear clerical error” and concluded that “the error is not evident from the face of the patent and the correction to the claim is not as simple as [Canatex] makes it seem.” Id. at *2–3. Instead, the court reasoned that the “perva- siveness of the error” in both the claims and the specifica- tion suggested that the error “was an intentional drafting choice and not an error at all.” Id. at 3. The court sug- gested that the patent’s drafter may have “intended to pro- vide an antecedent basis for a connection profile of the second part, thus making the error the use of ‘the’ instead of ‘a.’” Id. (emphasis added). And the court added that Canatex’s failure to seek correction from the U.S. Patent and Trademark Office (PTO) pursuant to 35 U.S.C. § 255, which expressly permits the PTO to correct certain clerical, typographical, and minor errors, suggested that the error is neither minor nor evident on the face of the patent. Claim Construction Order, at *3. For those reasons, the court concluded that it lacked authority to construe the claims to make Canatex’s proposed correction. Id. Case: 24-1466 Document: 58 Page: 9 Filed: 11/12/2025

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The district court entered a final judgment based on a joint stipulation. J.A. 8–11. Canatex appeals. We have jurisdiction under 28 U.S.C. § 1295(a)(1). 1 II On appeal, Canatex challenges as legally erroneous the district court’s dual determination that no error in the claim phrase at issue was evident on its face and that there was no unique evident correction. Under the very demand- ing standards for judicial correction of a claim term, as ap- plied here, we ask whether the intrinsic evidence clearly establishes that “second” in the claim phrase could only be reasonably understood by a relevant skilled artisan to mean “first.” We answer that question in the affirmative, and we do so de novo as a matter of claim interpretation based entirely on intrinsic evidence. See Pavo Solutions v. Kingston Technology Company, Inc., 35 F.4th 1367, 1373 (Fed. Cir. 2022); CBT Flint Partners, LLC v. Return Path, Inc., 654 F.3d 1353, 1358 (Fed. Cir. 2011); Ultimax Cement, 587 F.3d at 1346–47; Novo Industries, L.P. v. Micro Molds Corp., 350 F.3d 1348, 1353–54 (Fed. Cir. 2003). We review the district court’s claim construction based on intrinsic ev- idence de novo. Apple Inc. v. Wi-LAN Inc., 25 F.4th 960,

1 In February 2024, shortly after the district court entered its final judgment and Canatex appealed, Canatex sought correction of the disputed language from the PTO pursuant to 35 U.S.C. § 255 and 37 C.F.R. § 1.323, making arguments similar to those it has made to us. See Letter from Joseph P. Anderson III, Canatex Counsel, to PTO Cer- tificate of Corrections Branch (Feb. 13, 2024); Canatex’s Opening Br. at 14 n.4. The PTO denied Canatex’s proposed correction in March 2025, stating without elaboration that the “corrections requested [sought] to change the scope of the patented claims.” Patent Examiner’s Response, Deny- ing Certificate of Correction (Mar. 25, 2025), ECF No. 54, Ex. A. Case: 24-1466 Document: 58 Page: 10 Filed: 11/12/2025

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967 (Fed. Cir. 2022); Teva Pharmaceuticals USA, Inc. v. Sandoz, Inc., 574 U.S. 318, 331 (2015). The district court here properly did not rely on any findings of fact about ex- trinsic evidence, as defendants’ expert did not supply evi- dence of extra-patent usage or other extra-patent facts that could alter the conclusion from the intrinsic evidence. See, e.g., Teva Pharmaceuticals USA, Inc. v. Sandoz, Inc., 789 F.3d 1335, 1342 (Fed. Cir. 2015) (explaining limits on the role of expert evidence); Phillips v. AWH Corp., 415 F.3d 1303, 1318 (Fed. Cir. 2005) (en banc) (similar); J.A. 1695– 1702 (defendants’ expert discussing only intrinsic evi- dence). A Governing precedent recognizes the propriety of judi- cial correction of erroneous wording of a claim, as a matter of claim construction, when a very demanding standard is met. Almost a century ago, the Supreme Court in I.T.S. Rubber Co. v. Essex Rubber Co. corrected an obvious and minor mistake in a claim, concluding that the word “rear” was erroneously omitted through clerical error and the claim had to be construed to include the word. 272 U.S. 429, 442–43 (1926). The Court held that the correction was “not in any real sense [ ] a re-making of the claim” but in- stead “merely g[ave the claim] the meaning which was in- tended by the applicant and understood by the examiner.” Id. at 442. Based on Essex, our court has repeatedly held that judicial correction of errors in patents is proper in nar- row circumstances. See, e.g., Pavo, 35 F.4th at 1373–74; CBT Flint, 654 F.3d at 1358–59; Ultimax Cement 587 F.3d at 1353; Group One, Ltd. v. Hallmark Cards, Inc., 407 F.3d 1297, 1303 (Fed. Cir. 2005); Novo, 350 F.3d at 1357. The standard for judicial correction is a demanding one. We have made a correction for “an obvious and cor- rectable error in the claim, the construction of which is not subject to reasonable debate.” CBT Flint, 654 F.3d at 1358. Our cases articulate several elements of the standard. Case: 24-1466 Document: 58 Page: 11 Filed: 11/12/2025

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First, one necessary requirement is that “the error must be ‘evident from the face of the patent,’” Pavo, 35 F.4th at 1373 (quoting Group One, 407 F.3d at 1303), i.e., obvious, as de- termined “‘from the point of view of one skilled in the art,’” id. (quoting Ultimax, 587 F.3d at 1353). Second, another necessary requirement is that “[c]orrection is appropriate ‘only if (1) the correction is not subject to reasonable debate based on consideration of the claim language and the spec- ification and (2) the prosecution history does not suggest a different interpretation of the claims.’” Pavo, 35 F.4th at 1373 (quoting Novo, 350 F.3d at 1354). Third, we have ruled that “[a] district court may correct ‘obvious minor ty- pographical and clerical errors in patents.’” Id. (quoting Novo, 350 F.3d at 1357). We have not stated that element as a necessary requirement, which it may well be, but we here assume that it is. The just-stated demanding standard for judicial correc- tion via claim construction, when rigorously applied as it must be, takes account of the primacy of “the public notice function of patents.” Phillips, 415 F.3d at 1319. If an error is evident on the face of the patent, and the correction is the only reasonable understanding of the intrinsic evi- dence, at least if the correction makes only a small change in claim language, the relevant reader of the patent—a per- son of ordinary skill in the art, Phillips, 415 F.3d at 1312– 13—is constructively aware of the intended meaning, to be given effect by a court carrying out claim construction with its established, limited role for correction. The standard also respects Congress’s choice to make only prospective the corrections the PTO makes under 35 U.S.C. § 255, as that provision covers a broader class of errors—which, for example, are “not limited to obvious errors” and so can re- sult in a claim scope different from the one that relevant readers would understand from the pre-alteration lan- guage. Novo, 350 F.3d at 1356–57. A judicial correction determines the meaning the claim always had, id., and the rigorous standard for such a correction avoids the Case: 24-1466 Document: 58 Page: 12 Filed: 11/12/2025

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alteration-of-understanding problem underlying the pro- spectivity rule for PTO correction. Finally, the standard for judicial correction of patent claims is akin to a standard for judicial correction of other legal language set forth in the prominent guide to legal interpretation generally, ANTONIN SCALIA & BRYAN A. GARNER, READING LAW: THE INTERPRETATION OF LEGAL TEXTS (2012): “A provision may be either disregarded or judicially corrected as an error (when the correction is textually simple) if failing to do so would result in a disposition that no reasonable person could approve.” Id. at 234. B We conclude that Canatex is entitled to judicial correc- tion in this case. For reasons that overlap, the existence of an error in the phrase at issue is evident (obvious) on the face of the patent, and there is only one reasonable correc- tion, considering all the intrinsic evidence, including the prosecution history. That correction, changing “second” to “first,” plainly is simple and “minor” as a textual matter. And it follows that the fact of error and uniqueness of the small correction mean that the error is properly character- ized as a minor clerical or typographical error. We elabo- rate on (1) the obviousness of the error on the face of the patent and (2) the uniqueness of a reasonable correction. 1 We conclude that the error in the claim language—“to release the connection profile of the second part”—is obvi- ous on the face of the patent. Beginning with the claim language, a relevant artisan would immediately see that, as written, there is an error in the claim. The phrase at issue plainly requires an antecedent (“the connection pro- file of the second part”), but no “connection profile of the second part” has previously been mentioned in the claim. In addition, the reference to releasing a (nowhere identi- fied) “connection profile of the second part” makes no sense on the face of the claim language. As explained above, the Case: 24-1466 Document: 58 Page: 13 Filed: 11/12/2025

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clauses defining the structure require a component of the second part (“releasable engagement profile”) to engage with (by embracing internally) the “connection profile of the first part” and, upon movement of the locking piston from a “locking position” to a “release” position, to release some component by “radial expansion.” A relevant reader would immediately see that something was off in language that speaks of releasing, through the releasable engage- ment profile’s radial expansion, anything but the very com- ponent embraced in the connected state (the connection profile of the first part)—as made clear even by the name “releasable engagement profile.” An undefined notion of the second part’s engagement component releasing a part of the second part itself is jarringly anomalous in this claim. All of this makes the error evident on the face of the claim. The error of referring to a “connection profile of the sec- ond part” is also evident on the face of the specification. Nothing in the figures or their descriptions shows a “con- nection profile” in the second part. The Abstract and two passages in the written description use the same language as the claim, ’122 patent, Abstract; id., col. 1, lines 33–34; col. 3, lines 31–32, and one of those written-description pas- sages makes plain to a relevant reader that this usage was erroneous. The passage, referring to the patent’s figures, states: Releasable engagement profile 26 is locked in place by a locking piston 32, which moves axially along second part 14 between a locking position, shown in FIGS. 2 and 3, that locks releasable engagement profile 26 into engagement with connection profile 16 of the first part, and a release position, shown in FIG. 1, that permits releasable engagement pro- file 26 to release connection profile 16 of second part 14. ’122 patent, col. 3, lines 25–32 (underlining added). In the underlined phrase, the specification refers to “connection Case: 24-1466 Document: 58 Page: 14 Filed: 11/12/2025

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profile 16” as being “of second part 14.” But the figures clearly show “connection profile 16” as being of first part 12; the above-quoted passage itself refers to “connection profile 16 of the first part,” id., col. 3, line 29; and the spec- ification, introducing these components, makes that clear: “Second part 14 has a releasable engagement profile 26 that releasably engages connection profile 16 of first part 12.” Id., col. 3, lines 10–11 (italics added). A relevant reader had to understand that the passage attributing the connection profile 16 to the second part 14 was erroneous— and so must be the other references to the connection pro- file of the “second” part. We conclude that it is evident on the face of the patent that the claim language at issue contains an error. 2 We also conclude that the proper correction is not “sub- ject to reasonable debate based on consideration of the claim language and the specification.” Novo, 350 F.3d at 1354. The only reasonable correction is the changing of “second” to “first” in the claim language at issue. That is what the claim language as a whole and the specification both show “the very character of the invention requires.” Alloc, Inc. v. International Trade Commission, 342 F.3d 1361, 1370 (Fed. Cir. 2003). We have already explained why that is so. What is released, by radial expansion of the second part’s releasable engagement profile, is clearly meant to be the connection profile of the first part, which is what the releasable engagement profile embraces to con- nect the first and second parts. We reject defendants’ arguments that there are other reasonable corrections. One such argument is that the de- vice contains a “connection profile” on the second part, though not so named in the figures or the specification, so that the disputed claim phrase could be corrected to retain “second”—presumably by changing “the” to “a” or by add- ing earlier language to the claim to provide an antecedent. Case: 24-1466 Document: 58 Page: 15 Filed: 11/12/2025

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See Defendants’ Response Br. at 38–39; Claim Construc- tion Order, at *3. Defendants propose “tubing connector 22” or “some other possible connection profile on the second part that is not depicted in the figures or further described” as the possible connection profile of the second part that the patent drafter might have meant to identify. Defend- ants’ Response Br. at 38–39; J.A. 1699. This construction is illogical. Tubing connector 22, which is not called a “con- nection profile,” is, as depicted in Figure 1, located on the far proximal (toward the surface) end of the second part of the device; it is not a component of the device involved in the connection or disconnection of the device’s two parts, which is the plain function of the connection profile. ’122 patent, Figure 1; id., col. 2, lines 56–62. Instead, “as . . . known in the art,” tubing connector 22 connects the device to the tool string—the wireline up to the surface. Id. Tub- ing connector 22 cannot functionally be “the connection profile of the second part” to which the claims refer. And defendants do not identify any other component of the de- vice that could serve as the connection profile of the second part. We see no reasonable basis for reading the disputed claim language as intended to refer to some unidentified connection profile located on the second part of the device. Defendants’ expert opined that the errors in the claims “are not simply the result of a copy and paste mistake” and are instead “a deliberate (yet unclear) drafting choice” be- cause “the language differs between some of the instances.” Defendants’ Response Br. at 50; J.A. 1698 (comparing ’122 patent, col. 1, lines 33–34 (“the connection profile of the sec- ond part”), with id., col. 3, lines 31–32 (“connection profile 16 of second part 14”)). This slight difference in wording cannot reasonably be thought significant. The only change in the language is the addition of the numbers correspond- ing to the labels on the patent’s figures; these labels do not change the understanding of the device’s components. Moreover, as indicated above, the specification passage at col. 3, lines 31–32, by its undisputable mistake, shows that Case: 24-1466 Document: 58 Page: 16 Filed: 11/12/2025

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the patentee plainly meant the connection profile of the first part, as stated in col. 3, lines 10–11. Defendants additionally proffer a list of potential cor- rections to the claim language. Defendants’ Response Br. at 38; J.A. 1698–1702. These proposals are unavailing. One proposal is not substantively different from changing “second” to “first”: It would simply delete “of the second part,” leaving “the connection profile,” which by the called- for antecedent would refer to the only previously men- tioned connection profile, namely, the “connection profile of the first part.” Cf. CBT Flint, 654 F.3d at 1358–59 (deter- mining that, where a relevant artisan could conclude that three reasonable alternative constructions have the “same scope and meaning,” the district court had authority to make a correction). All the other proposed alternatives would alter the scope and meaning of the claims signifi- cantly from what is clear from the claim language as a whole and is described in the specification. See, e.g., De- fendants’ Response Br. at 38–39 (providing alternative cor- rections such as “a release position that permits the releasable engagement profile locking piston to expand ra- dially to shift sufficiently to allow a sufficient force to be applied to a release the connection profile of the second part to allow disengagement of the releasable engagement profile from the connection profile of the first part,” a cor- rection that changes the context of the claims). These pro- posals are not reasonably debatable alternatives to Canatex’s simple, logical change of “second” to “first.” Finally, we have no basis for concluding that the pros- ecution history in this case suggests any construction of the disputed language other than Canatex’s proposed correc- tion. See Pavo, 35 F.4th at 1373; Novo, 350 F.3d at 1354. Here, the district court did not conclude, and defendants make no convincing argument to us in their brief, that the prosecution history in this case precludes correction if, as we have concluded, the error at issue is evident on the face of the patent and the proposed correction is the only Case: 24-1466 Document: 58 Page: 17 Filed: 11/12/2025

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reasonable one based on the claims and specification. In this respect, the present case is properly distinguished from Chef America, Inc. v. Lamb-Weston, Inc., 358 F.3d 1371, 1374–75 (Fed. Cir. 2004), in which, as we have ex- plained, this court relied significantly on the prosecution history, Pavo, 35 F.4th at 1375. In these circumstances, we conclude that the correction of “second” to “first” is the unique correction that captures the claim scope a reasonable relevant reader would under- stand was meant based on the claim language and specifi- cation. III For the foregoing reasons, we reverse the district court’s claim construction and remand the matter for fur- ther proceedings consistent with the corrected claims. Costs awarded to Canatex. REVERSED AND REMANDED