United States: Claim Scope Limited When Specification Describes Feature As "Essential" And "Universal" To All Embodiments

In X2Y Attenuators, LLC v. International Trade Commission, No. 13-1340 (Fed. Cir. July 7, 2014), the Federal Circuit affirmed the ITC's claim construction and determination of no violation under 19 U.S.C. § 1337.

X2Y Attenuators, LLC ("X2Y") is the owner of three related patents:  U.S. Patent Nos. 7,609,500 ("the '500 patent"); 7,916,444 ("the '444 patent"); and 8,023,241 ("the '241 patent") (collectively "the patents-in-suit").  The patents-in-suit relate to structures for reducing electromagnetic interference in electrical circuits.  The patents-in-suit describe shielding electrodes to reduce "parasitic capacitance" between the electrodes by alternating arrangements of shielded and unshielded electrodes.  Slip op. at 3 (citation omitted).  X2Y filed a complaint in the ITC accusing Intel Corporation and other intervenors (collectively "Intel") of unlawful importation of microprocessors that infringed the patents-in-suit.  At the ITC, the parties disputed whether the "electrode" terms in the claims were limited to a "sandwich" configuration, where a center conductor is flanked by a pair of differential or oppositely charged conductors.  Id. at 5.  The ALJ construed the electrode terms to require a sandwich configuration based on specification disavowal, and the ITC adopted the ALJ's construction.  X2Y conceded noninfringement based on the construction and the ITC found no violation.  X2Y appealed.

"The patents' statements that the presence of a common conductive pathway electrode positioned between paired electromagnetically opposite conductors is 'universal to all the embodiments' and is 'an essential element among all embodiments or connotations of the invention' constitute clear and unmistakable disavowal of claim scope."  Slip op. at 7.

On appeal, the Federal Circuit considered the construction of the electrode terms, concluding that the ITC's construction was correct.  The Court observed that, in the specification, a common conductive pathway electrode positioned between paired electromagnetically opposite conductors was described as "universal to all the embodiments" and "an essential element among all embodiments or connotations of the invention," constituting clear and unmistakable disavowal of claim scope.  Id. at 7.  The Court first explained that labeling an element as "essential" may give rise to disavowal, and the patents-in-suit explained that the sandwich configuration was not only "essential," but was an "essential element among all embodiments or connotations of the invention."  Id. at 7-8 (citations omitted).  The Court also noted that the '444 patent incorporated by reference statements of its parent patent, U.S. Patent No. 5,909,350, that the sandwich configuration was a "feature[] universal to all the embodiments."  Id. (alteration in original) (citation omitted).  The Court explained that, like language stating that a feature is essential, this language demonstrates a clear intention to limit the claim scope by "using words or expressions of manifest exclusion or restriction."  Id.  (quoting Teleflex, Inc. v. Ficosa N. Am. Corp., 299 F.3d 1313, 1324 (Fed. Cir. 2002)).  Although the Court recognized that the passage included permissive language about the selection of materials in the configuration, the specification also explained that no matter which material is used, the general sandwich configuration remains the same.  The Court thus concluded that the patents-in-suit's statements constituted clear and unmistakable disavowal of claim scope. 

The Court then considered X2Y's argument that some disclaimers were inapplicable because they appeared only in priority patents.  The Court rejected this argument, noting that the "essential element" disavowal appeared explicitly in the '500 patent, and that the '500 and '444 patents incorporated by reference priority patents that included disavowal language.  The Court explained that incorporating by reference effectively makes the incorporated disclosure part of the host patent, as if it was explicitly contained therein.  Although the Court recognized that the possibility that a clear and unmistakable disavowal of an incorporated patent may no longer be applicable when placed in the context of the host patent, it rejected that argument in this case, finding that the patents-in-suit's statements that all conceivable configurations use the sandwich configuration limited the scope of the patents-in-suit. 

Accordingly, the Court affirmed the ITC's construction of the "element" claim terms and affirmed the finding of no violation.

Judge Reyna concurred, writing separately to address an issue at the ITC that did not affect the Court's decision.  Judge Reyna noted that the ALJ and the ITC limited the asserted claims to "the invention" disclosed in the priority patents.  Reyna Concurrence at 2.  According to Judge Reyna, this was error because the ALJ and ITC failed to objectively construe the claims before deciding the priority dates for the claims.

Judges:  Moore (author), Reyna (concurring), Wallach

[Appealed from ITC]

This article previously appeared in Last Month at the Federal Circuit, August, 2014.

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