CAFC debates the meaning of "is" in Kruse v. Volkswagen
Kruse v. Volkswagen
The patents in question relate to combustion in auto engines:
The ’562 and ’904 Patents share nearly identical written descriptions1 and describe internal combustion en- gines controlled to “precisely regulate the fuel/air mixture for combustion and exhaust emission con- trol.” ’562 Patent col. 5 ll. 15-17. In the disclosed sys- tems, fuel is injected in first and second fractions at different points in the operating cycle of the engine, resulting in a combustion process having “a constant volume (isochoric) phase and a constant temperature (isothermal) phase.” Id. col. 2 ll. 64-66. More specifically, in one aspect of the disclosed inventions, a first predeter- mined fraction of fuel is introduced and, when the piston is substantially at top dead center, ignited resulting in a substantially isochoric or constant volume process. At the beginning of the expansion stroke, a second fraction of the fuel is introduced. The combustion resulting from the second fraction is a substantially isothermal or constant temperature process. The isothermal process occurs at a significantly lower temperature than that of conventional internal combustion engines having the same or lower compression ratio, thereby limiting undesirable NOx emissions. Id. col. 3 ll. 9-41.
The point of contention is the last claim element
wherein the combustion as a result of the in- troduction of the second fraction is a substantially isothermal process.
Id. col. 12 ll. 34-57 (emphasis added).
The issue involves the term "substantially"
The focus of the present litigation is on the final, emphasized “substantially isothermal process” limitation. Claim 2 at issue de- pends from claim 1. Id. col. 12 ll. 58-59. Claim 9 of the ’904 Patent, also at issue, is similar to claim 1 of the ’562 Patent, and has the same “substantially isothermal process” limitation. ’904 Patent col. 14 ll. 30-53.
A local district court rule was at issue and the CAFC noted:
Questions on the validity or interpretation of Rule 3-6 are governed by the law of this court. See O2 Micro Int’l Ltd. v. Monolithic Power Sys., Inc., 467 F.3d 1355, 1364- 65 (Fed. Cir. 2006) (“Monolithic”). “Decisions enforcing local rules in patent cases” are reviewed for an abuse of discretion and “will be affirmed unless clearly unreasona- ble, arbitrary, or fanciful; based on erroneous conclusions of law; clearly erroneous; or unsupported by any evi- dence.” Id. at 1366-67.
Volkswagen responds that the district court correctly construed the “substantially isothermal process” limita- tion. Volkswagen argues that the claim language equates the second fraction combustion with the isothermal pro- cess by using “is.” Volkswagen also asserts that the use of the definite article “the” in “the combustion” confirms the district court’s construction. Volkswagen supports this argument further by citing Intamin, Ltd. v. Magnetar Technologies, Corp., 483 F.3d 1328, 1335-36 (Fed. Cir. 2007), in which this court construed “‘the length’” to mean “the full length” of a part and Haemonetics Corp. v. Baxter Healthcare Corp., 607 F.3d 776, 782-83 (Fed. Cir. 2010), in which this court construed “‘the centrifugal unit’” to be the entire unit. Volkswagen argues that “substantially” indicates that the temperature can vary, but that the question of whether the isothermal combustion can be less than the entire second fraction combustion is a ques- tion of infringement—rather than a question of claim construction.
On the use of the word --is--, the CAFC noted
“[I]s” ties the subject (“the combustion”) to the following description (“a substantially isothermal process”). The subject is introduced with the definite article (“the”), indicating a partic- ular combustion, i.e., the combustion of the second fraction. “[T]he combustion . . . is a substantially iso- thermal process,” does not indicate that only a portion of the combustion is isothermal; instead, it indicates that the entire combustion is isothermal. This interpretation is context-specific and is not negated by the fact that other uses of “is,” such as when it is an auxiliary verb, result in different constructions. See DePuy Spine, Inc. v. Medtronic Sofamor Danek, Inc., 469 F.3d 1005, 1014 (Fed. Cir. 2006) (stating that the claim language “the screw ‘head is pressed against the hollow spherically-shaped portion’” does not “indicate how much of the hollow spher- ically-shaped portion must be ‘pressed against’ the screw head”).
The CAFC brought up a case not cited by the parties:
While not cited by the parties, Regents of the Universi- ty of California v. Dakocytomation California, Inc., 517 F.3d 1364 (Fed. Cir. 2008), is more closely analogous to the present case. Regents considered the construction of the claim limitation “heterogeneous mixture of labeled unique sequence nucleic acid fragments,” which the district court construed to mean “heterogeneous mixture of labeled nucleic acid fragments that includes only unique sequence fragments.” Id. at 1371 (internal quota- tion marks omitted). The appellants argued, in part, that “the [district] court erred by interpreting that language to mean that the heterogeneous mixture excludes repetitive sequences” because “the dependent claims of the patent clearly require repetitive sequences.” Id. The appellants relied on “the proposition that dependent claims are presumed to be of narrower scope than the independent claims from which they depend under the doctrine of claim differentiation.” Id. at 1375 (internal quotation marks omitted). This court found this argument “unper- suasive.” Id (...)
In Regents, the prosecution history overcame the presumption [from claim differentiation] and the court conclud- ed that the correct construction excluded repetitive se- quences, “notwithstanding the presence of certain dependent claims that do not exclude them.” Id. Like- wise, as here, the presumption will be overcome where the ordinary meaning of the words in an independent claim do not admit to a construction that would embrace a claim dependent therefrom.
As to the doctrine of equivalents:
This court has cited Moore as an example of the prop- osition that an antithesis of a claim limitation, or an alternative that is too different, cannot be an equivalent. See Brilliant, 707 F.3d at 1348; Planet Bingo, LLC v. GameTech Int’l, Inc., 472 F.3d 1338, 1345 (Fed. Cir. 2006). Moore states,
In this case, we hold that the applicant’s use of the term ‘‘majority’’ is not entitled to a scope of equivalents covering a minority for at least two reasons. First, to allow what is undisputedly a minority (i.e., 47.8%) to be equivalent to a majori- ty would vitiate the requirement that the ‘‘first and second longitudinal strips of adhesive . . . ex- tend the majority of the lengths of said longitudi- nal marginal portions.’’ If a minority could be equivalent to a majority, this limitation would hardly be necessary, since the immediately pre- ceding requirement of a ‘‘first and second longitu- dinal strips of adhesive disposed in said first and second longitudinal marginal portions, respective- ly, of said first face’’ would suffice.
Second, it would defy logic to conclude that a minority—the very antithesis of a majority—could be insubstan- tially different from a claim limitation requiring a majority, and no reasonable juror could find oth- erwise.
Judge Wallach dissented
I do not agree with the majority’s interpretation of “the combustion . . . is a substantially isothermal process” limitation as recited in claim 1. In particular, I find the disputed claim language ambiguous, and the specification reveals that claim 1 does not require combustion as a result of the second fuel fraction to be substantially isothermal from the beginning until the end of that com- bustion. I therefore respectfully dissent. (...)
I agree with the majority that claims should be con- strued based on precepts of English grammar, that the doctrine of claim differentiation is not a hard and fast rule, and that claims need not encompass every disclosed alternative embodiment. See Majority Op. 12, 15–16. I also agree that this court is not required to rewrite claims to preserve their validity. See id. at 17.
Independently, these judicial doctrines aiding in claim construction are not dispositive, and are frequently rebut- ted. However, when a particular interpretation of a claim simultaneously violates all of these doctrines, such a construction may not be tenable. In fact, a construction that excludes disclosed embodiments, violates the doc- trine of claim differentiation, and invalidates a dependent claim cannot stay true to the claim language and the written description of the invention. Power Integrations, Inc. v. Fairchild Semiconductor Int’l, Inc., 711 F.3d 1348, 1361 (Fed. Cir. 2013) (“The construction that stays true to the claim language and most naturally aligns with the patent’s description of the invention will be, in the end, the correct construction.”).
“It is axiomatic that a dependent claim cannot be broader than the claim from which it depends.” Alcon Research, Ltd. v. Apotex Inc., 687 F.3d 1362, 1367 (Fed. Cir. 2012); AK Steel Corp. v. Sollac & Ugine, 344 F.3d 1234, 1242 (Fed. Cir. 2003) (“Under the doctrine of claim differentiation, dependent claims are presumed to be of narrower scope than the independent claims from which they depend.”). By con- struing “substantially isothermal process” in claim 1 to exclude the processes expressly recited in dependent claim 4, the majority broadens the scope of a dependent claim over the independent claim from which it depends, violating the doctrine of claim differentiation.