Canatex Completion Solutions, Inc., Appeal No. 2024-1466 (Fed. Cir. Nov. 12, 2025)

In our Case of the Week, the Federal Circuit revisited and clarified the “demanding standard for judicial correction via claim construction,” which permits a court in narrow circumstances to modify claim language to correct obvious errors.  Plaintiff Canatex’s U.S. Patent No. 10,794,122 was directed to an oil- and gas-drilling device with a separable, “downhole” component that could be released by an operator on the surface—for example if it becomes stuck—and separated from the rest of the device for later retrieval.  The parties’ dispute concerned the claim phrase “the connection profile of the second part,” which Canatex argued a skilled artisan would understand to mean “the connection profile of the first part.”  Notwithstanding that the language appeared in every independent claim and was reflected multiple times in the patent’s specification, the Federal Circuit agreed with Canatex that it was an obvious error subject to judicial correction, reversing the lower court’s determination that the claims were indefinite.

The ’122 patent has three independent claims, of which claim 1 was treated as representative and is reproduced below, with the Federal Circuit panel’s internal labels and emphases added.  Also reproduced below are figures from the patent—with the panel’s coloring and markup—showing the configuration of the recited components.

The underlined phrase in clause [b][3] appeared in every independent claim, and was also recited in the patent’s abstract and specification, e.g.:

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.

During claim construction, the defendants argued that the phrase “the connection profile of the second part” lacked any antecedent basis, rendering all claims indefinite under 35 U.S.C. § 112.  The district court agreed, finding that the “pervasiveness of the error” suggested an intentional drafting choice, for example reflecting some abandoned intention to recite a “connection profile” for the “second part,” such that the error might have been the claim’s use of the definite article “the” instead of “a.”  On appeal, however, reviewing the lower court’s determination from the intrinsic evidence de novo, the Federal Circuit reversed.

The Federal Circuit first explained the “very demanding standards for judicial correction of a claim term,” which requires, first, that the error be evident from the face of the patent, and second, that a unique, proposed correction is not subject to reasonable debate based on the claim language, specification, and prosecution history.  These requirements reflect “the primacy of the public notice function of patents,” and are intended to preserve “the meaning the claim always had,” of which others are “constructively aware” by virtue of the error’s obviousness.  The Court expressly declined to say whether the error must always be a “minor typographical [or] clerical error[]” as suggested by certain precedent, but found that description to also apply in this case.

Applying these requirements to the case at bar, the Federal Circuit first found that the error was obvious on the face of the patent, noting the claims require “a component of the second part (‘releasable engagement profile’) to engage with (by embracing internally) the ‘connection profile of the first part’ [limitation [b][ii] above] and, upon movement of the locking piston… to release some component… [limitation [b][iii] above].”  The Court explained a skilled artisan would “immediately see that something was off” in the language reciting “releasing” “anything but the very component embraced in the connected state (the connection profile of the first part),” and that “[a]n undefined notion of the second part’s engagement component releasing a part of the second part itself is jarringly anomalous in this claim.”  The Court further noted that nothing in the patent’s figures or their descriptions suggested any “connection profile” of the “second part” notwithstanding the occasional superficial references in the text, which the court found a “relevant reader had to understand” was also an error.

Having found an error obvious on the face of the patent, the Court further found that the appropriate reading—that the recited “connection profile” was of the first part, not the second—was not subject to reasonable debate.  For example, defendants argued that the drafter could have been referring to some other portion of the second part—such as “tubing connector 22”—as a “connection profile.”  The panel dismissed this argument as “illogical,” noting that the “tubing connector” was plainly not involved in any connection function (see figures reproduced above), and that defendants did not identify any other component of the “second part” that the recited “connection profile” could have been referring to.  The court rejected multiple other alternative corrections proposed by defendants, finding, for example, that the proposed language was not substantively different from changing “second part” to “first part,” or that their changes would so significantly alter the scope and meaning of the claims that they were “not reasonably debatable alternatives to Canatex’s simple, logical change of ‘second’ to ‘first.’”

Because the claims were properly subject to judicial correction, the Federal Circuit reversed the district court’s claim construction order finding indefiniteness, and remanded for further proceedings.

The opinion can be found here.

By Jason A. Wrubleski

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Smartrend Manufacturing Group (SMG), Inc. v. Opti-Luxx Inc., Appeal Nos. 2024-1616, -1650 (Fed. Cir. Nov. 13, 2025)

Following a jury verdict of infringement and issuance of a permanent injunction in a case concerning components of “school bus” vehicle signs, the Federal Circuit reversed denial of the defendant’s motion for judgment as a matter of law and vacated the injunction.  In so ruling, the Court emphasized the limiting effect of “as shown and described” language in design patents.  The Court explained that such language, when used to define a design, limits the scope of the patent’s protection to the drawings and accompanying written description of the patent.  In this case, the patent at issue contained oblique shading on certain surfaces, which the Manual of Patent Examining Procedures explained could indicate transparency or translucency.  But because the patent included “as shown and described” language in defining the design, both the drawings and the accompanying description were used to limit the patent’s scope.  The patent’s description stated that “oblique shading lines… denote transparency.”  Thus, the claims were limited to surfaces that were transparent, but not translucent.  By expanding “transparency” to include translucency, the district court improperly broadened the claimed design, requiring vacatur of the infringement judgment.

On a related utility patent, the Court found judgment of the defendant was also appropriate where an asserted “equivalent” did not perform the functions recited in the specification for the claim element at issue.

The opinion can be found here.

By Jason Evans

This article summarizes aspects of the law and does not constitute legal advice. For legal advice with regard to your situation, you should contact an attorney.