       NOTE: This disposition is nonprecedential.


  United States Court of Appeals
      for the Federal Circuit
                 ______________________

      KRUSE TECHNOLOGY PARTNERSHIP,
               Plaintiff-Appellant,

                            v.

              VOLKSWAGEN AG AND
    VOLKSWAGEN GROUP OF AMERICA, INC.
     (doing business as Audi of America, Inc.),
                Defendants-Appellees.
               ______________________

                       2012-1352
                 ______________________

   Appeal from the United States District Court for the
Central District of California in No. 10-CV-1066, Judge
James V. Selna.
                 ______________________

                Decided: October 8, 2013
                ______________________

   DAVID G. JANKOWSKI, Knobbe, Martens, Olson & Bear,
LLP, of Irvine, California, argued for plaintiff-appellant.
With him on the brief were JOHN B. SGANGA, JR. and
MARKO R. ZORETIC.

    JOHN F. SWEENEY, Locke Lord LLP, of New York, New
York, argued for defendants-appellees. With him on the
brief were STEVEN F. MEYER and JOSEPH A. FARCO.
2         KRUSE TECHNOLOGY PARTNERSHIP    v. VOLKSWAGEN AG
                  ______________________

    Before NEWMAN, LINN, and WALLACH, Circuit Judges.

     Opinion for the court filed by Circuit Judge LINN.

    Dissenting opinion filed by Circuit Judge WALLACH.

LINN, Circuit Judge.

    Kruse Technology Partnership (“Kruse”) appeals a
summary judgment of non-infringement of the claims of
Kruse’s U.S. Patents No. 5,265,562 (“’562 Patent”) and
No. 6,058,904 (“’904 Patent”) in favor of Volkswagen AG
and Volkswagen Group of America, Inc. (collectively,
“Volkswagen”) and challenges several decisions of the
district court that led up to the summary judgment of
non-infringement. Order GRANTING Volkswagen De-
fendants’ Motion for Summary Judgment (Fld 1-20-12) &
Daimler Defendants’ Motion for Summary Judgment as to
Non-Infringement (Fld 1-23-12), Kruse Tech. P’ship v.
Daimler AG, No. 10-CV-1066 (C.D. Cal. Mar. 21, 2012),
ECF No. 497 (“Summary Judgment Order”); Order Grant-
ing in Part and Denying in Part Plaintiff’s Motion for
Leave to Amend Infringement Contentions, Kruse Tech.
P’ship v. Daimler AG, No. 10-CV-1066 (C.D. Cal. Dec. 7,
2011), ECF No. 424 (“Order Denying Leave to Amend”);
Order on Claim Construction, Kruse Tech. P’ship v. Daim-
ler AG, No. 10-CV-1066 (C.D. Cal. Sept. 29, 2011), ECF
No. 359 (“Claim Construction Order”). This court con-
cludes that the district court’s claim construction was
correct, that the district court did not abuse its discretion
in denying Kruse leave to amend its infringement conten-
tions, and that the district court properly granted sum-
mary judgment. Thus, this court affirms the judgment of
the district court.
KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG         3
                      I. BACKGROUND

                  A. The Patents in Suit

     The ’562 and ’904 Patents share nearly identical writ-
ten descriptions 1 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 operation of the engine
system in accordance with the disclosed inventions is
graphically shown in Fig. 4(B), reproduced below, in
which the constant volume phase is depicted as line 2-3
and the constant temperature phase is depicted as line 3-
4. Id. col. 6 l. 59 to col. 7 l. 8.




    1    Thus, in general, only the specification of ’562 Pa-
tent is cited herein.
4        KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG




    Another embodiment, described and graphically illus-
trated in Fig. 8(B), reproduced below, produces combus-
tion not just in two phases, but in three: constant volume,
constant pressure, and constant temperature. The three
phases are depicted in Fig. 8(B) as lines 3-4, 4-5, and 5-6,
respectively. Id. col. 11 l. 37 to col. 12 l. 6. Distinct
portions of the second fuel fraction are introduced in the
constant pressure and constant temperature phases. Id.
This embodiment is described as pertaining to circum-
stances in which there is “a value to limiting maximum
cylinder pressure.” Id. col. 11 ll. 37-38.
KRUSE TECHNOLOGY PARTNERSHIP   v. VOLKSWAGEN AG         5




                   B. Claims at Issue

   Claim 1 of the ’562 Patent states:

       1. A method of operating an internal combus-
   tion expanding chamber piston engine for provid-
   ing limited temperature combustion, said engine
   having (1) at least one cylinder and an associated
   piston for forming a combustion chamber, said
   piston having a top dead center position, (2) an
   operating cycle including an intake stroke, a com-
   pression stroke and an expansion stroke, and (3) a
   fuel introduction system, said method comprising
   the steps of:

      forming a predetermined fuel/air mixture by
          introducing a predetermined fraction of
          the total fuel required for complete com-
          bustion of the process air in the combus-
          tion chamber;

      igniting said fuel/air mixture when the piston
          is substantially at top dead center; and
6        KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG
        introducing substantially at the beginning of
            the expansion stroke, a second fraction of
            the total fuel required for complete com-
            bustion,

        wherein the combustion of the fuel/air mixture
           resulting from the fuel first introduced is a
           substantially constant volume process;
           and

        wherein the combustion as a result of the in-
           troduction of the second fraction is a sub-
           stantially isothermal process.

Id. col. 12 ll. 34-57 (emphasis added). The focus of the
present litigation is on the final, emphasized “substantial-
ly 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.

    While not asserted in the present case, claim 4 of the
’562 Patent is relevant to the construction of the claims at
issue. Claim 4 depends from claim 3, which depends from
claim 1. ’562 Patent col. 12 ll. 60-65. Claim 4 states,

    4. A method, as described in claim 3, wherein:

        the combustion of said first mentioned prede-
            termined fraction is limited to a preselect-
            ed maximum pressure; and wherein,

        the second fraction of the total fuel is supplied
            so as to provide, first, constant pressure
            combustion until a preselected maximum
            combustion temperature is reached, and
KRUSE TECHNOLOGY PARTNERSHIP      v. VOLKSWAGEN AG       7
            secondly, isothermal combustion at said
            preselected maximum temperature.

Id. col. 12 l. 65 to col. 13 l. 5 (emphasis added).

                  C. Previous Proceedings

     This is not the first case in which the ’562 Patent and
’904 Patent have been litigated. In Kruse’s prior cases,
the district courts construed the language of the “substan-
tially isothermal process” limitation at issue. Order on
Claim Construction at 30, Kruse Tech. P’ship v. Gen.
Motors Co., No. 09-CV-4970 (C.D. Cal. July 14, 2010),
ECF No. 86 (construing the limitation to mean “average
cylinder temperature remains substantially constant after
the second fraction of fuel is supplied” (internal quotation
marks omitted)); Order Denying Defendant’s Motion for
Summary Judgment at 7-8, Kruse Tech. P’ship v. Caterpil-
lar, Inc., No. 04-CV-10435 (C.D. Cal. Oct. 5, 2008), ECF
No. 196 (construing the limitation to mean “average
cylinder temperature remains substantially constant after
the second fraction of fuel is introduced” (internal quota-
tion marks omitted)). The district court in the present
case modified the construction: “the combustion resulting
from the second fuel fraction results in average cylinder
temperature that remains substantially constant from the
beginning until the end of that combustion.” Claim Con-
struction Order at 12, 23 (emphasis added) (internal
quotation marks omitted). In making its ruling, the
district court indicated that the claims would be indefinite
if they did not specify the duration of the isothermal
process.

    Following the district court’s claim construction,
Kruse sought leave to amend its infringement conten-
tions. Kruse sought to redefine which of the multiple fuel
injections in the accused engines was the “second frac-
tion.” Kruse sought to have the “post” injection alone be
8        KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG
the “second fraction,” whereas previously Kruse argued
that the “main” and “post” injections together were the
“second fraction.” In ruling on Kruse’s motion to amend,
the district court applied the Northern District of Califor-
nia Patent Local Rules effective March 1, 2008.

        Under Patent Local Rule 3-6 [(“Rule 3-6”)], a
    party may amend or modify its preliminary in-
    fringement contentions only by order of the Court
    upon a timely showing of good cause. The “good
    cause” inquiry first considers whether plaintiff
    was diligent in amending its contentions and then
    considers prejudice to the non-moving party. The
    party seeking to amend its contentions bears the
    burden of establishing diligence.

Order Denying Leave to Amend at 2-3 (citations omitted)
(internal quotation marks omitted). The district court
found that Kruse was diligent. Nevertheless, the district
court denied Kruse leave to amend its infringement
contentions, concluding that the proposed changes “would
cause undue prejudice to . . . [Volkswagen] because fur-
ther claim construction and discovery would likely be
required.” Id. at 9.

    The district court then granted summary judgment in
favor of Volkswagen. The district court first found no
evidence supporting a claim of literal infringement when
the “post” and “main” injections of the fuel in the accused
engines together did not result in combustion at a sub-
stantially constant temperature “from the beginning until
the end of that combustion.” Summary Judgment Order
at 11 (internal quotation marks omitted). The district
court also found that there was no infringement under the
doctrine of equivalents as a matter of law. Specifically,
the district court reasoned that while Kruse’s expert
sought to show for the accused Volkswagen engines that
“the isothermally combusted portions are between 23%
KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG          9
and 48% of the total fuel injected,” id. at 13-14, allowing
these percentages to be equivalent to the claim limitation
“would depart too far from being isothermal from the
beginning to the end,” id. at 15. The district court con-
cluded that allowing less than half of the combustion “to
be isothermal would be contrary to the meaning of this
limitation and would vitiate the limitation.” Id.

    This court     has    jurisdiction   under   28    U.S.C.
§ 1295(a)(1).

                       II. DISCUSSION

                  A. Standard of Review

    This court reviews claim construction de novo. Lock-
heed Martin Corp. v. Space Sys./Loral, Inc., 324 F.3d
1308, 1318 (Fed. Cir. 2003). “[A] determination of in-
fringement, both literal and under the doctrine of equiva-
lents, is a question of fact,” id., but this court reviews the
application of the all elements rule and the associated
concept of vitiation de novo. See id. at 1320-21.

    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.

        We review summary judgment decisions un-
    der regional circuit law. The Ninth Circuit re-
    views the grant of summary judgment de novo.
    Summary judgment is appropriate if the movant
    shows that there is no genuine dispute as to any
10        KRUSE TECHNOLOGY PARTNERSHIP    v. VOLKSWAGEN AG
     material fact and the movant is entitled to judg-
     ment as a matter of law. At the summary judg-
     ment stage, we credit all of the nonmovant’s
     evidence and draw all justifiable inferences in its
     favor.

Brilliant Instruments, Inc. v. GuideTech, LLC, 707 F.3d
1342, 1344 (Fed. Cir. 2013) (citations omitted) (internal
quotation marks omitted).

                  B. Claim Construction

     Kruse argues that the district court incorrectly con-
strued the “substantially isothermal process” limitation
and improperly expanded the earlier claim construction
by supplementing it with the italicized phrase in the
following construction: “the combustion resulting from the
second fuel fraction results in average cylinder tempera-
ture that remains substantially constant from the begin-
ning until the end of that combustion.”               Claim
Construction Order at 12, 23 (emphasis added) (internal
quotation marks omitted). Kruse argues that this con-
struction departs from the ordinary meaning of the claim
language in the context of the specification and other
claims, argues that the specification and prosecution
history do not narrowly redefine or disavow the full scope
of the “substantially isothermal process” limitation, and
proposes that the “substantially isothermal process”
limitation means simply that “the combustion as a result
of supplying the second fraction results in an average
cylinder temperature that remains substantially con-
stant.” Pl.-Appellant’s Br. 42 (internal quotation marks
omitted). Moreover, Kruse argues that the claim says “a
result,” which indicates that there can be more than one
result; that “substantially” in the claim indicates that the
isothermal process can deviate slightly from ideal both in
temperature and in duration and need not be restricted to
temperature only; and that the construction should not
KRUSE TECHNOLOGY PARTNERSHIP    v. VOLKSWAGEN AG        11
require that the entire duration of the second fraction
combustion be isothermal because that would create a
conflict with and raise validity concerns with respect to
claim 4—directed to the embodiment of Fig. 8(B) of the
’562 Patent—which calls for the second fraction combus-
tion to be divided into two portions, of which only the
second is isothermal. Kruse also argues that the con-
struction should not require that the entire duration of
the second fraction combustion be isothermal because the
specification teaches that the ideal combustion processes
described cannot be achieved in the real world and states
that variation in temperature and in process duration is
expected. Kruse finally argues that the district court
cited no evidence of indefiniteness and that the district
court should not have construed the claim to preserve its
validity before determining that it was ambiguous.

    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. Volkswagen also argues that neither claim
4 nor the embodiment in Fig. 8 requires a construction of
the “substantially isothermal process” term contrary to its
12       KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG
ordinary meaning. Moreover, Volkswagen argues that
Intamin also supports the district court’s construction in
that a dependent claim in that case did not alter the
ordinary meaning of the independent claim, although the
district court did not rely on Intamin. Volkswagen notes
that the district court’s construction reads on the embod-
iment in Fig. 4, in which the combustion temperature is
constant for the entire second fraction combustion. Final-
ly, Volkswagen argues that the claims would be indefinite
under Kruse’s construction.

    “[W]ords of a claim are generally given their ordinary
and customary meaning,” which is the “the meaning that
the term would have to a person of ordinary skill in the
art in question at the time of the invention.” Phillips v.
AWH Corp., 415 F.3d 1303, 1312-13 (Fed. Cir. 2005) (en
banc) (internal quotation marks omitted). “[T]he claims
themselves,” “both asserted and unasserted,” “provide
substantial guidance as to the meaning of particular
claim terms.” Id. at 1314. “[T]he context in which a term
is used in the asserted claim can be highly instructive.”
Id. Also, “[a] claim must be read in accordance with the
precepts of English grammar.” In re Hyatt, 708 F.2d 712,
714 (Fed. Cir. 1983).

    Based on the ordinary and customary meaning of the
claim terms, the district court’s construction is correct. As
was the case in Intamin, the terms of the relevant limita-
tion when read together indicate the meaning of the
limitation itself. See 483 F.3d at 1335-36 (concluding that
“length” in the claim limitation a “‘conductive rail being
adapted to extend the length of the fixed device part’”
“encompasses the full length of the fixed device part”
based on the verb “extend,” the fact that “the term ‘length’
imparts information about the ‘fixed device part,’” and the
specification). The only permissible reading of the limita-
tion “the combustion . . . is a substantially isothermal
process,” ’562 Patent col. 12 ll. 55-57 (emphasis added), is
KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG        13
that it requires a substantially constant temperature for
the entire second fraction combustion. “[I]s” ties the
subject (“the combustion”) to the following description (“a
substantially isothermal process”). The subject is intro-
duced 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 language “a result” in the claim at issue
identifies the relevant combustion as that resulting from
the introduction of the second fraction and does not sug-
gest that the district court’s construction is incorrect. See
’562 Patent col. 3 ll. 34-36 (“The combustion resulting
from the introduction of the second fraction is a substan-
tially isothermal process.” (emphasis added)).            The
district court did not improperly add a durational limita-
tion to the claims because the durational limitation
derives from the language of the claim itself.

     Kruse and the dissent argue that “substantially” could
also refer to the duration of combustion, meaning that the
isothermal portion of the second fraction combustion need
not extend from beginning to end. But that ignores the
language and context of the entire claim phrase “wherein
the combustion as a result of the introduction of the
second fraction is a substantially isothermal process.” Id.
col. 12 ll. 55-57 (emphasis added). As the district court
correctly recognized, the relevant portion of the combus-
14        KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG
tion to consider is the entire second fraction combustion.
The word “substantially” in the “substantially isothermal
process” limitation indicates that under real-world condi-
tions the temperature can depart, to some limited extent,
from an ideal isothermal process. But the claim simply
cannot be read to cover methods in which the full dura-
tion of combustion of the second fraction is not substan-
tially isothermal.

    “Differences among claims can . . . be a useful guide in
understanding the meaning of particular claim terms.”
Phillips, 415 F.3d at 1314. But the present case differs
slightly from the common example of this proposition in
which “the presence of a dependent claim that adds a
particular limitation gives rise to a presumption that the
limitation in question is not present in the independent
claim.” Id. at 1315. In the present case, the question is
whether a limitation added in a dependent claim indicates
that the independent claim cannot exclude that limitation,
rather than indicating that the independent claim does
not already require that limitation. Volkswagen relies on
Intamin, but that case is not directly on point because in
that case the dependent claim’s validity did not depend on
the construction of the “length” term at issue:

     Dependent claim 10 addresses the embodiment
     where the conductive portion is connected to the
     movable device. With claim 1 specifying that the
     conductive rail extends the length of the fixed de-
     vice, dependent claim 10 may well be improper.
     Thus, Intamin urges this court to construe claim 1
     to retain the validity of claim 10. Under the prop-
     er construction of claim 1, dependent claim 10
     erases entirely a limitation of the fixed device part
     and is thus an improper dependent claim. Of
     course, dependent claim 10 has that effect under
     any reading of ‘‘length’’ in claim 1. Because claim
     1 requires the conductive portion to reach the
KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG          15
    length of the fixed device part and claim 10 places
    the conductive portion on the passenger car, claim
    10 is an improper dependent claim. Thus, con-
    struing claim 1 to mean end to end length does
    not in itself render claim 10 invalid.

483 F.3d at 1337. In the present case, the claim construc-
tion at issue is itself relevant to the validity of dependent
claim 4.

    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.

    Presumptions are rebuttable. We have held that
    while it is true that dependent claims can aid in
    interpreting the scope of claims from which they
    depend, they are only an aid to interpretation and
    are not conclusive. Indeed, the presumption cre-
    ated by the doctrine of claim differentiation is not
    a hard and fast rule and will be overcome by a
16        KRUSE TECHNOLOGY PARTNERSHIP    v. VOLKSWAGEN AG
     contrary construction dictated by the written de-
     scription or prosecution history.

Id. (citation omitted) (internal quotation marks and
alteration marks omitted). In Regents, the prosecution
history overcame the presumption 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.

    Kruse argues that interpreting claim 1 to require iso-
thermal combustion from beginning to end means the
claim will not read on the alternative embodiment of Fig.
8(B). This court’s precedent is clear that a claim need not
cover every disclosed embodiment. “The mere fact that
there is an alternative embodiment disclosed in the
asserted patent that is not encompassed by our claim
construction does not outweigh the language of the claim,
especially when the court’s construction is supported by
the intrinsic evidence.” August Tech. Corp. v. Camtek,
Ltd., 655 F.3d 1278, 1285 (Fed. Cir. 2011) (internal quota-
tion marks and alteration marks omitted).

    Kruse also argues that the district court’s claim con-
struction would conflict with claim 4. This court will not
redraft claim 1 contrary to its ordinary meaning to avoid
a conflict with claim 4. In Haemonetics, consistent with
the specification, this court concluded that the language of
the claim at issue—“‘[a] centrifugal unit comprising a
centrifugal component and a plurality of tubes’”—
“unambiguously define[d] ‘centrifugal unit’ as ‘comprising’
[the] two structural components,” and so the claim’s
further recitation of “‘the centrifugal unit’” could not be
read as only the vessel in the context of dimensional
KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG         17
limitations because that would ignore its antecedent basis
and would not give effect to all the claim’s language. 607
F.3d at 781-82. The district court had concluded “that
because the vessel with the tubing is larger than the
vessel alone, construing ‘centrifugal unit’ in the context of
the dimensional limitations to include the tubing would
yield an absurdity.” Id. at 782 (additional internal quota-
tion marks omitted). Nevertheless, this court concluded
that “we do not redraft claims to contradict their plain
language in order to avoid a nonsensical result.” Id.
Likewise, in the present case, we will not redraft inde-
pendent claim 1 contrary to its plain language to preserve
the validity of dependent claim 4. Even if there is an
“‘error’” in drafting, the claims as drafted are “what the
patentee claimed and what the public is entitled to rely
on.” Id. at 782-83.

     This court has considered the parties’ other argu-
ments and finds them unpersuasive. This court concludes
that the district court correctly construed the “substan-
tially isothermal process” limitation.

               C. Denial of Leave to Amend

    Northern District of California Local Rule 3-6 effec-
tive March 1, 2008, like the current Rule 3-6, states in
relevant part,

        Amendment of the Infringement Contentions
    or the Invalidity Contentions may be made only
    by order of the Court upon a timely showing of
    good cause. Non-exhaustive examples of circum-
    stances that may, absent undue prejudice to the
    non-moving party, support a finding of good cause
    include: (a) a claim construction by the Court dif-
    ferent from that proposed by the party seeking
    amendment . . . .
18       KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG
     In assessing “good cause,” the district court applied a
two-part test considering: (a) the diligence of the movant,
and (b) the prejudice to the non-moving party, relying on
CBS Interactive, Inc. v. Etilize, Inc., 257 F.R.D. 195, 201
(N.D. Cal. 2009) (citing Monolithic, 467 F.3d at 1366-68,
and applying the pre-2008 patent local rules). The dis-
trict court found that Kruse was diligent in seeking to
amend, but concluded that the amendment would cause
undue prejudice to Volkswagen in that the amended
contentions would necessitate further discovery and
require the construction of additional claim limitations.
The district court thus refused to permit Kruse to amend
its infringement contentions.

    Kruse argues that it was an abuse of discretion for the
district court to deny it leave to amend its infringement
contentions in response to the district court’s claim con-
struction. First, Kruse argues that it was unreasonable
for the district court to find undue prejudice to
Volkswagen based on the need for discovery. Kruse
argues that Volkswagen had time to conduct discovery:
Kruse served the proposed amended infringement conten-
tions before the close of fact discovery, before Volkswagen
took fact depositions, and before the exchange of expert
reports. Kruse argues that its proposed amendments
were not “a major change in its infringement theory,” Pl.-
Appellant’s Br. 54, and that it was relying on the same
data while changing its interpretation of the second
fraction to be a subset of the injections on which it previ-
ously relied. Kruse argues that Rule 3-6(a) contemplates
amendments after claim construction, that based on the
district court’s ruling no amount of diligence would have
allowed Kruse to amend, and that the district court’s
schedule alone prevented Kruse from amending. Second,
Kruse argues that it was unreasonable for the district
court to find undue prejudice to Volkswagen based on the
need for further claim construction because trial was
months away and the district court could have and should
KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG         19
have construed the additional terms. Kruse cites, among
other cases, O2 Micro International Ltd. v. Beyond Inno-
vation Technology Co., 521 F.3d 1351, 1362 (Fed. Cir.
2008) (“Beyond Innovation”), which states, “[w]hen the
parties present a fundamental dispute regarding the
scope of a claim term, it is the court’s duty to resolve it.”

     Volkswagen argues that it was not an abuse of discre-
tion for the district court to deny Kruse leave to amend.
First, Volkswagen argues that Kruse sought to amend its
infringement contentions near the close of fact discovery,
that fact discovery had closed by the time the district
court denied Kruse leave to amend, and that Volkswagen
could not obtain fact discovery on Kruse’s new theory of
infringement. Second, Volkswagen argues that Kruse’s
amended infringement contentions represented a major
change to its infringement theory that would have re-
quired further claim construction. Volkswagen argues
that simply because the district court can conduct further
claim construction does not mean that it abused its dis-
cretion in declining to permit a shift in Kruse’s infringe-
ment theory late in the proceeding.           Volkswagen
distinguishes the present case from the cases Kruse cites,
such as Beyond Innovation, because such cases addressed
whether the district court “needs to construe a term at
all” and “did not involve a motion to amend infringement
contentions, or a second Markman proceeding.” Defs.-
Appellees’ Br. 64. Third, Volkswagen argues that the
district court’s decision was consistent with Rule 3-6,
which provides no automatic right to amend infringement
contentions after claim construction but requires leave of
the court.

    The patent local rules “seek to balance the right to
develop new information in discovery with the need for
certainty as to the legal theories” and “require parties to
crystallize their theories of the case early in the litigation
so as to prevent the ‘shifting sands’ approach to claim
20       KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG
construction.” Monolithic, 467 F.3d at 1364, 1366 (addi-
tional internal quotation marks omitted). “[T]his court
defers to the district court when interpreting and enforc-
ing local rules so as not to frustrate local attempts to
manage patent cases according to prescribed guidelines.”
Genentech, Inc. v. Amgen, Inc., 289 F.3d 761, 774 (Fed.
Cir. 2002).

    Kruse served the proposed amendments before the
close of discovery, however, fact discovery was nearing its
end and was closed by the time the district court decided
Kruse’s motion to amend. While the parties disagree
whether Kruse sought a major change, it was a change to
the theory of infringement that would likely have meant
re-opening of Markman proceedings and extending dis-
covery. Although the question is close, this court cannot
conclude that the district court abused its discretion in
finding prejudice given the late stage of the proceedings at
which Kruse presented the alternative infringement
theories.

    Kruse identifies no controlling case, including Beyond
Innovation, that would require the district court to permit
the amendments and construe the additional claim terms
in the present circumstances. Beyond Innovation con-
cluded that a district court cannot decline to resolve a
dispute on the scope of the claims and allow the issue to
be submitted to the jury. 521 F.3d at 1361-63. Beyond
Innovation does not speak to whether a district court
must allow an amendment to infringement contentions
that would require it to conduct additional claim con-
struction and extend discovery at a late stage of the
proceedings.

    Kruse is correct that when the non-moving party is
prejudiced, there may be no amount of diligence by the
moving party that would allow an amendment to the
infringement contentions. But Rule 3-6 requires more
KRUSE TECHNOLOGY PARTNERSHIP    v. VOLKSWAGEN AG        21
than diligence; it requires that there be no “undue preju-
dice to the non-moving party.” Rule 3-6 does not provide
a right to amend regardless of prejudice to the non-
moving party. Here, there is sufficient evidence of preju-
dice that the district court’s finding is not unreasonable,
arbitrary, clearly erroneous, or unsupported by any
evidence.

               D. Doctrine of Equivalents

    Kruse acknowledges that the grant of Volkswagen’s
summary judgment motion of no literal infringement “was
an inevitable consequence of its denying Kruse leave to
amend its infringement contentions.” Pl.-Appellant’s Br.
59. Kruse argues that the district court erred in conclud-
ing that Kruse’s infringement theory vitiated the dura-
tional limitation of the “substantially isothermal process”
limitation. Kruse distinguishes prior cases, such as
Moore U.S.A., Inc. v. Standard Register Co., 229 F.3d
1091 (Fed. Cir. 2000), contending that it does not seek to
capture the antithesis of a second fraction that combusts
entirely isothermally, because that would be a second
fraction with no isothermal combustion. Instead, Kruse
argues that the accused products’ operation differs from
the construed claim limitation by degree. Specifically,
Kruse argues that the isothermal combustion of 23% to
48% of the second fraction 2 in the accused products is an
insubstantial difference from isothermal combustion from
beginning to end. Kruse also argues that the district
court disregarded its evidence on equivalency or imper-
missibly resolved genuine issues of material fact.


   2    While Kruse initially appeared to indicate that
23% to 48% of the fuel for the cycle combusts isothermal-
ly, the cited portions of the record and Plaintiff-
Appellant’s Reply Brief indicate that 23% to 48% of the
second fraction combusts isothermally.
22        KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG
     Volkswagen argues that the district court correctly
concluded that Kruse’s theory of infringement, which
would allow 23% to 48% of the second fraction combustion
to be equivalent to “from the beginning until the end of
that combustion,” would vitiate that requirement.
Volkswagen acknowledges that the claim says “substan-
tially isothermal,” that rounded corners are permissible,
that the duration need not be 100% of the second fraction,
and that perhaps even 80% would be sufficient; but
Volkswagen argues that the low percentage of the second
fraction that combusts isothermally in the accused prod-
ucts cannot be covered by the claims. See Oral Arg. at
20:27-21:22,           available         at         http://
www.cafc.uscourts.gov/oral-argument-recordings/2012-
1352/all. Volkswagen argues that the present case is
analogous to Moore. Volkswagen argues that the district
court did not impermissibly consider a binary choice
under the doctrine of equivalents, as indicated by the
district court’s statement that “to allow an ‘appreciable’
portion, as represented by the above percentages, to
manifest an equivalency would depart too far from being
isothermal from the beginning to the end.” Summary
Judgment Order at 15. Volkswagen also argues that
Kruse failed to provide evidence supporting a finding of
equivalency.

   This court clarified the vitiation inquiry in DePuy
Spine:

         It is important to note that when we have held
     that the doctrine of equivalents cannot be applied
     to an accused device because it ‘‘vitiates’’ a claim
     limitation, it was not to hold that the doctrine is
     always foreclosed whenever a claim limitation
     does not literally read on an element of an accused
     device; such an interpretation of the “all elements”
     rule would swallow the doctrine of equivalents en-
     tirely. Any analysis of infringement under the
KRUSE TECHNOLOGY PARTNERSHIP    v. VOLKSWAGEN AG            23
   doctrine of equivalents necessarily deals with sub-
   ject matter that is beyond, ignored by, and not in-
   cluded in the literal scope of a claim. A holding
   that the doctrine of equivalents cannot be applied
   to an accused device because it ‘‘vitiates’’ a claim
   limitation is nothing more than a conclusion that
   the evidence is such that no reasonable jury could
   conclude that an element of an accused device is
   equivalent to an element called for in the claim, or
   that the theory of equivalence to support the con-
   clusion of infringement otherwise lacks legal suf-
   ficiency.

469 F.3d at 1018-19 (citations omitted) (internal quota-
tion marks and alteration marks omitted).

    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
24        KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG
     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.

229 F.3d at 1106 (alteration in original) (citation omitted).

    In the present case, the district court ruled, as a
matter of law, that Kruse’s theory of infringement under
the doctrine of equivalents lacks legal sufficiency in that
the proposed equivalent is contrary to or would vitiate the
claim limitation of combustion from the beginning until
the end.

    Here the district court correctly construed the claim
language to mean that the combustion from the second
fuel fraction “results in average cylinder temperature that
remains substantially constant from the beginning until
the end.” Claim Construction Order at 12, 23 (internal
quotation marks omitted). While the claim limitation, as
construed, by no means precludes some departure from
the entirety of the second fraction combustion, we find no
error in the district court’s conclusion that the claim term
is not flexible enough to allow the 23% to 48% duration of
the second fraction combustion to be equivalent to the
entirety of the second fraction combustion. Allowing such
a percentage to be equivalent to combustion over the full
duration is contrary to the meaning of the claim limita-
tion and would render it meaningless. Isothermal com-
bustion for less than half of the second fraction
combustion cannot logically be considered insubstantially
different from combustion from beginning to end; and, as
in Moore, no reasonable juror could find otherwise. See
229 F.3d at 1106. Thus, this court need not reach the
issue of the sufficiency of Kruse’s evidence. For the
foregoing reasons, this court affirms the district court’s
KRUSE TECHNOLOGY PARTNERSHIP   v. VOLKSWAGEN AG        25
grant of summary judgment to Volkswagen on Kruse’s
theory of infringement under the doctrine of equivalents.

                    III. CONCLUSION

    Based on the foregoing analysis, this court concludes
that the district court correctly construed the claim lan-
guage in question and did not abuse its discretion in
denying Kruse’s motion for leave to amend, and affirms
the district court’s grant of summary judgment of no
infringement.

                      AFFIRMED
        NOTE: This disposition is nonprecedential.


  United States Court of Appeals
      for the Federal Circuit
                 ______________________

      KRUSE TECHNOLOGY PARTNERSHIP,
              Plaintiff-Appellant,

                            v.

              VOLKSWAGEN AG AND
    VOLKSWAGEN GROUP OF AMERICA, INC.
     (doing business as Audi of America, Inc.),
                Defendants-Appellees.
               ______________________

                       2012-1352
                 ______________________

   Appeal from the United States District Court for the
Central District of California in No. 10-CV-1066, Judge
James V. Selna.
                 ______________________

WALLACH, Circuit Judge, dissenting.
    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.
2        KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG



     The district court initially construed “the combus-
tion . . . is a substantially isothermal process” to mean
that “average cylinder temperature remains substantially
constant after the second fraction of fuel is supplied.” J.A.
5335–37. Subsequently the district court set aside that
construction and narrowed its interpretation of the term,
construing the limitation to mean “the combustion result-
ing from the second fuel fraction results in average cylin-
der temperature that remains substantially constant from
the beginning until the end of that combustion.” J.A. 9–
12. Accordingly, the district court narrowed the limita-
tion with a durational requirement—from the beginning
until the end of that combustion—which the majority now
affirms.
    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.”).
KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG          3



         The majority holds that the only permissible read-
ing of the limitation “the combustion . . . is a substantially
isothermal process,” requires a substantially constant
temperature for the entire second fraction combustion.
According to the majority, “is” ties the subject (“combus-
tion”) to the description following (“a substantially iso-
thermal process”). Because the subject is introduced with
the definite article “the” (“the combustion of the second
fraction”) the majority concludes that the ordinary and
customary meaning requires “the” entire combustion—
from the beginning to the end—to be isothermal. The
majority holds the word “substantially” in the “substan-
tially isothermal process” limitation modifies only the
“isothermal process.” Although that interpretation is
reasonable, the claim language also supports an at least
equally plausible alternative interpretation.
    “Substantially” can also refer to the duration of the
combustion. For example, combustion initiated by a fuel
fraction may begin at a certain temperature which may
subsequently increase over time eventually arriving at an
isothermal state. In that instance, the average cylinder
temperature may remain substantially constant even if
the cylinder was not in an isothermal state from the
beginning of the combustion. Indeed, the district court’s
earlier construction encompassed this interpretation of
“substantially isothermal process.” By including the
durational requirement, however, the majority effectively
negates the patentee’s use of the approximate term “sub-
stantially.” Without this term, the claim would read: “the
combustion . . . is a[n] . . . isothermal process,” which is
more parallel to the majority’s construction requiring the
isothermal process to occur from the beginning until the
end of the combustion. The introduction of “substantially”
modifies this strict requirement by allowing the combus-
tion as a result of the introduction of the second fuel
fraction to fluctuate prior to the combustion settling into
an isothermal state. This claim language is ambiguous.
4        KRUSE TECHNOLOGY PARTNERSHIP      v. VOLKSWAGEN AG



     Recourse to the specification resolves this ambiguity.
Claims do not stand alone, and the remaining intrinsic
evidence aids in construing the disputed term. Phillips v.
AWH Corp., 415 F.3d 1303, 1315 (Fed. Cir. 2005) (en
banc). The specification is highly relevant and usually
dispositive in any claim construction analysis making it
the single best guide to the meaning of a disputed term.
Id. (internal quotation marks and citation omitted).
    Unlike the claim language, the specification provides
ample guidance and context, which necessarily conflict
with the majority’s claim construction. For instance, the
“ideal” combustion processes, ’562 col. 11 ll. 18–19, depict-
ed in Figures 4(A)–4(C) are instructive. Figure 4(B) is
shown below:




    In this figure, Path 3 to 4 represents an ideal iso-
thermal combustion process as a result of a second fuel
fraction that uses the remaining fuel not expended during
Path 1 to 2 and Path 2 to 3. Id. col. 7 ll. 4–6. The specifi-
cation explains how “[r]eal engine paths will depart to
some extent from the ideal cycles shown [in Figure 4] due
to timing, heat and friction losses. These factors will
manifest themselves in the cycle diagram as, for example,
rounded corners and displacements of the process.” Id. col.
11 ll. 19–24. The “rounded corners” and “displacements”
as applied to Path 3 to 4 will introduce, inter alia, shifting
and/or concavity to the depicted straight line altering the
depiction of a perfectly isothermal state to one that is
“substantially isothermal.” Figure 8, an embodiment of
KRUSE TECHNOLOGY PARTNERSHIP     v. VOLKSWAGEN AG         5



the invention at issue, illustrates such a deviation from
the “ideal” cycle.
    In reference to Figure 8, the specification discloses
combustion as a result of the second fuel fraction that can
be divided into two sequential states: (1) combustion
occurring at constant pressure, and (2) combustion occur-
ring at constant temperature. Id. col. 11 l. 64–col. 12 l. 2.
Figure 8 is depicted below:




    As illustrated, the combustion at Path 4 to 5 occurs at
constant pressure and is provided by the introduction of a
second fuel fraction. Id. col. 11 ll. 64–66. The combustion
during Path 5 to 6 occurs at constant temperature—
isothermally. Id. col. 11 l. 66–col. 12 l. 2. This figure and
its corresponding disclosure in the specification clearly
indicate that the combustion need not be isothermal from
the beginning of the combustion, as the majority’s con-
struction requires. Rather, Figure 8 shows that the
isothermal process may begin at some later time after the
second fuel fraction is introduced.         This combustion
process reasonably may be characterized as “substantially
isothermal.” Accordingly, a departure from a perfectly
isothermal process encompasses combustion that may be
“substantially” isothermal—one that may not necessarily
begin with and end in such a state—much like the embod-
6        KRUSE TECHNOLOGY PARTNERSHIP    v. VOLKSWAGEN AG



iment depicted in Figure 8 and those described as devia-
tions from the “ideal” cycles illustrated in Figure 4.
    The majority nevertheless reasons that a claim con-
struction need not encompass every embodiment, and
determines that the “ordinary meaning” of “substantially
isothermal process” excludes the embodiment illustrated
by Figure 8. Majority Op. 16. Even if the claim language
were as clear as the majority believes, the majority’s
construction excludes, not only the embodiment depicted
in Figure 8, but also those embodiments described in the
’562 patent that encompass “real” engines. As discussed
above, the patent is directed to embodiments that depart
from “ideal” combustion processes, which may not be
perfectly isothermal from the beginning until the end of
the combustion. Thus, the majority’s requirement that
the isothermal process occur from the beginning until the
end of the combustion excludes these disclosed embodi-
ments as well. That result cannot be correct. Nellcor
Puritan Bennett, Inc. v. Masimo Corp., 402 F.3d 1364,
1368 (Fed. Cir. 2005) (“The fact that the construction
adopted by the district court and advocated by [appellee]
would have the effect of placing all the embodiments of
the invention outside the scope of the claims is powerful
evidence that the court’s construction is incorrect.”).
    In addition to improperly excluding these disclosed
embodiments, the majority’s construction does not give
sufficient weight to the doctrine of claim differentiation.
Figure 8 is particularly claimed in dependent claim 4,
which reads in part:
    [T]he second fraction of the total fuel is supplied
    so as to provide, first, constant pressure combus-
    tion until a preselected maximum combustion
    temperature is reached, and secondly, isothermal
    combustion at said preselected maximum temper-
    ature.
KRUSE TECHNOLOGY PARTNERSHIP    v. VOLKSWAGEN AG         7



’562 patent col. 13–ll. 1–5. Claim 4 depends from claim 3,
which depends from claim 1 including the disputed “sub-
stantially isothermal process” limitation. “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.
    Nonetheless, the majority reasons that the presump-
tion the doctrine of claim differentiation provides is
rebutted “where the ordinary meaning of the words in an
independent claim do not admit to a construction that
would embrace a claim dependent therefrom.” Majority
Op. 16. At the same time, however, the majority renders
claim 4 superfluous. That cannot be. See, e.g., Rhine v.
Casio, Inc., 183 F.3d 1342, 1345 (Fed. Cir. 1999) (“Claims
should be so construed, if possible, as to sustain their
validity.”) (internal quotation marks, citation, and altered
capitalization omitted).
    Specifically, because a dependent claim narrows the
claim from which it depends, it must “‘incorporate . . . all
the limitations of the claim to which it refers.’” Alcon
Research, 687 F.3d at 1367 (quoting 35 U.S.C. 112 ¶ 4
(2006)). Indeed, context of the claims as whole informs
the proper construction of terms. Abbott Labs. v. Syntron
Bioresearch, Inc., 334 F.3d 1343, 1351 (Fed. Cir. 2003).
Claim 1 recites broadly that combustion as a result of the
introduction of the second fraction is a substantially
isothermal process. Consequently, the combustion result-
ing from the second fuel fraction recited in dependent
8        KRUSE TECHNOLOGY PARTNERSHIP   v. VOLKSWAGEN AG



claim 4 while describing two sequential states—isobaric
and isothermal—as a whole must still be “substantially
isothermal.” Requiring the combustion to be isothermal
from beginning to end negates claim 4 and threatens its
validity. A construction which simultaneously violates
the doctrine of claim differentiation and writes out claim
4 must be erroneous.
    For these reasons, I would construe “the combustion .
. . is a substantially isothermal process” to mean that
“average cylinder temperature remains substantially
constant after the second fraction of fuel is supplied.”
Accordingly, I would reverse the district court’s claim
construction ruling and remand for further proceedings.
