Maxell, Ltd. v. Amperex Technology Limited

United States Court of Appeals
for the Federal Circuit
______________________
MAXELL, LTD.,
Plaintiff-Appellant
v.
AMPEREX TECHNOLOGY LIMITED,
Defendant-Appellee
______________________
2023-1194
______________________
Appeal from the United States District Court for the
Western District of Texas in Nos. 6:21-cv-00347-ADA, 6:21-
cv-01007-ADA, Judge Alan D. Albright.
______________________
Decided: March 6, 2024
______________________
HILARY L. P RESTON, Vinson & Elkins LLP, Austin, TX,
argued for plaintiff-appellant. Also represented by CORBIN
CESSNA, J EFFREY T A-HWA HAN, ERIK SHALLMAN; ERIC
J OSEPH K LEIN, P AIGE HOLLAND WRIGHT , Dallas, TX.
D AVID SPENCER BLOCH , Greenberg Traurig LLP, San
Francisco, CA, argued for defendant-appellee. Also repre-
sented by HAROLD H. D AVIS , J R.; YANG L IU, East Palo Alto,
CA.
______________________
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MAXELL, LTD. v. AMPEREX TECHNOLOGY LIMITED 2
Before P ROST , T ARANTO, and CHEN, Circuit Judges.
T ARANTO, Circuit Judge.
Maxell, Ltd. owns U.S. Patent No. 9,077,035, which de-
scribes and claims a rechargeable lithium-ion battery. Am-
perex Technology Limited is a manufacturer of lithium-ion
batteries. In two now-consolidated actions, Maxell as-
serted infringement, and Amperex challenged the validity,
of claims of the ’035 patent. The ’035 patent’s claims re-
quire at least two lithium-containing transition metal ox-
ides, represented by formulas that include a transition
metal element M1, and, as relevant here, two limitations of
the claims state requirements for that element. The dis-
trict court held the claim language defining M1 to be indef-
inite on the ground that the two limitations contradicted
each other, Maxell, Ltd. v. Amperex Technology Ltd.,
No. 21-cv-00347, 2022 WL 16858824, at *19–21 (W.D. Tex.
Nov. 10, 2022) (Claim Construction Order), and on that ba-
sis the court entered partial final judgment in favor of Am-
perex, J.A. 18–20. We reverse, concluding that there is no
contradiction and therefore no indefiniteness. The case is
remanded for further proceedings.
I
A
The ’035 patent, titled “Nonaqueous Secondary Battery
and Method of Using the Same,” describes and claims a
lithium-ion battery with a positive electrode, a negative
electrode, and a nonaqueous electrolyte. ’035 patent, Ab-
stract. The limitations of the patent’s claims primarily con-
cern the positive electrode and the electrolyte. See id., col.
29, line 20, through col. 30, line 58. All claims of the patent
include a positive electrode that includes at least two lith-
ium-containing transition metal oxides with different aver-
age particle sizes. Id., col. 4, lines 6–9; id., col. 29, lines 21–
26. The transition metal oxides are represented in the
claims by formulas that include, in relevant part, a transi-
tion metal element M1. Id., col. 29, lines 28–31, 43–49.
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MAXELL, LTD. v. AMPEREX TECHNOLOGY LIMITED 3
Claim 1, the sole independent claim of the ’035 patent,
reads as follows (letters added to label the limitations):
1. A nonaqueous secondary battery comprising:
[a] a positive electrode having a positive elec-
trode mixture layer, a negative electrode, and
a nonaqueous electrolyte,
[b] wherein the positive electrode comprises, as
active materials, at least two lithium-contain-
ing transition metal oxides having different av-
erage particle sizes, and the lithium-containing
transition metal oxide having the smallest av-
erage particle size is a lithium-containing tran-
sition metal oxide represented by the formula
(1): Li x M1y M2zM3v O 2
[c] wherein M1 represents at least one tran-
sition metal element selected from Co, Ni
and Mn, M2 represents Mg and at least one
metal element selected from the group consist-
ing of Ti, Zr, Ge, Nb, Al and Sn, M3 represents
at least one element selected from the group
consisting of Na, K, Rb, Be, Ca, Sr, Ba, Sc, Y,
La, Hf, V, Ta, Cr, Mo, W, Tc, Re, Fe, Ru, Rh,
Cu, Ag, Au, B, Ca, In, Si, P and Bi, and x, y, z
and v are numbers satisfying the equations re-
spectively: 0.97≤x<1.02, 0.8≤y<1.02,
0.002≤z≤0.05, and 0≤v≤0.05, and has an aver-
age particle size from 2 μm to 10 μm, and the
lithium-containing transition metal oxide hav-
ing the largest average particle size is a lith-
ium-containing transition metal oxide
represented by the formula (2):
Li aM1bM2c M3d O 2
[d] wherein M1, M2 and M3 are the same as de-
fined in the formula (1), and a, b, c and d are
numbers satisfying the equations respectively:
0.97≤a<1.02, 0.8≤b<1.02, 0.0002≤c≤0.02, and
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MAXELL, LTD. v. AMPEREX TECHNOLOGY LIMITED 4
0≤d≤0.02, and has an average particle size from
5 μm to 25 μm,
[e] wherein said electrolyte contains a fluorine-
containing organic solvent,
[f] wherein the content of Co in the transi-
tion metal M1 of the formulae (1) and (2) is
from 30% by mole to 100% by mole,
[g] wherein the content of said lithium-contain-
ing transition metal oxide having the smallest
average particle size in the lithium-containing
transition metal oxides is from 5% by weight to
60% by weight,
[h] wherein the content of said lithium-contain-
ing transition metal oxide having the largest
average particle size in the lithium-containing
transition metal oxides is from 40% by weight
to 95% by weight, and
[i] wherein an amount of said fluorine-contain-
ing organic solvent is 0.1% by weight to 30% by
weight based on the whole weight of the elec-
trolyte.
Id., col. 29, line 20, through col. 30, line 9 (emphases
added).
B
In April 2021, Amperex filed a complaint in district
court in New Jersey seeking a declaratory judgment of non-
infringement of several Maxell patents, including the ’035
patent. Complaint, Amperex Technology Ltd. v. Maxell
Ltd., No. 21-cv-08461 (D.N.J. Apr. 6, 2021), ECF No. 1; J.A.
1341–430. In response, Maxell brought an affirmative pa-
tent-infringement action against Amperex in the Western
District of Texas on the same set of patents. Complaint,
Maxell Ltd. v. Amperex Technology Ltd., No. 21-cv-00347
(W.D. Tex. Apr. 8, 2021), ECF No. 1; J.A. 1431–565. In
January 2022, the cases were consolidated in the Western
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MAXELL, LTD. v. AMPEREX TECHNOLOGY LIMITED 5
District of Texas. J.A. 1996–97; see also In re Amperex
Technology Ltd., No. 2022-105, 2022 WL 135431 (Fed. Cir.
Jan. 14, 2022) (denying Amperex’s mandamus petition
challenging the transfer of its New Jersey action).
In February 2022, the district court conducted claim-
construction proceedings and issued an order that, among
other things, addressed the two above-highlighted wherein
clauses and held to be indefinite the following phrase that
combines them: “M1 represents at least one transition
metal element selected from Co, Ni and Mn, . . . wherein
the content of Co in the transition metal M1 of the formulae
(1) and (2) is from 30% by mole to 100% by mole.” J.A. 25.
On November 10, 2022, the district court issued a claim
construction order setting forth its reasoning. Claim Con-
struction Order, at *19–21. The court reasoned that “the
plain language of the claim recites a contradiction,” be-
cause the first limitation does not require the presence of
cobalt (nickel or manganese suffices), so cobalt is “op-
tional,” whereas the second limitation does require cobalt.
Id. at *20; see also id. at *21 (repeating point that the first
limitation describes “options”).
Pursuant to Federal Rule of Civil Procedure 54(b), the
district court severed the ’035 patent claims and counter-
claims from the remainder of the case and entered partial
final judgment in favor of Amperex and against Maxell
with respect to all claims and counterclaims involving the
’035 patent. J.A. 18–20. Maxell filed a timely notice of ap-
peal on November 14, 2022, J.A. 99, within the 30 days al-
lowed under 28 U.S.C. § 2107(a). We have jurisdiction to
review the partial final judgment under 28 U.S.C.
§ 1295(a)(1).
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MAXELL, LTD. v. AMPEREX TECHNOLOGY LIMITED 6
II
Under 35 U.S.C. § 112, ¶ 2 (2006),1 a patent specifica-
tion “shall conclude with one or more claims particularly
pointing out and distinctly claiming the subject matter
which the applicant regards as his invention.” Patent
claims that fail to meet the “particularly pointing out and
distinctly claiming” requirement are invalid for indefinite-
ness. When “claims, read in light of the specification delin-
eating the patent, and the prosecution history, fail to
inform, with reasonable certainty, those skilled in the art
about the scope of the invention,” they are indefinite. Nau-
tilus, Inc. v. Biosig Instruments, Inc., 572 U.S. 898, 901
(2014). “Indefiniteness must be proven by clear and con-
vincing evidence.” Sonix Technology Co. v. Publications In-
ternational, Ltd., 844 F.3d 1370, 1377 (Fed. Cir. 2017). We
decide indefiniteness de novo where, as here, there are no
material underlying factual issues. See Cox Communica-
tions, Inc. v. Sprint Communication Co., 838 F.3d 1224,
1228 (Fed. Cir. 2016); Biosig Instruments, Inc. v. Nautilus,
Inc., 783 F.3d 1374, 1377–78 (Fed. Cir. 2015).
The district court based its indefiniteness conclusion on
its determination that “the plain language of [claim 1] re-
cites a contradiction” in that “[t]he first part of the claim
recites a Markush group where [cobalt] is not necessarily
required to be in the claimed compound while the second
part of the claim recites that [cobalt] is necessarily re-
quired. For an element to simultaneously be optional and
required is a contradiction on its face.” Claim Construction
Order, at *20. That rationale, we conclude, is incorrect, but
not because a contradiction in a claim cannot produce
1 Section 112 was amended by the Leahy-Smith
America Invents Act (AIA), Pub. L. No. 112-29, 125 Stat.
284, 296–97 (2011), but the pre-AIA version applies to this
case. The AIA relabeled § 112 ¶ 2 as § 112(b) but made no
change in the language material to this case.
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MAXELL, LTD. v. AMPEREX TECHNOLOGY LIMITED 7
indefiniteness. Rather, there is no contradiction in the
claim language at issue in this case.
The first of the two limitations at issue regarding M1–
limitation [c]—states one requirement a transition metal
element must meet to come within the claim: It must con-
tain cobalt, nickel, or manganese. The second limitation at
issue—limitation [f]—states a second requirement: The
transition metal element must contain cobalt at a content
of 30% to 100% by mole. It is perfectly possible for a tran-
sition metal element to meet both requirements. The two
limitations are therefore not contradictory.
It makes no difference, at least here, that the two re-
quirements are placed in separate limitations—rather
than both appearing in limitation [c]. Such placement does
not alter the logical point that it is possible to meet both
requirements, meaning that there is no contradiction.
Moreover, a reader seeking to understand “the scope of the
invention,” Nautilus, 572 U.S. at 901, is charged with
knowing not only that any particular claim language must
be “read in the context of the full claim,” Salazar v. AT&T
Mobility LLC, 64 F.4th 1311, 1318 (Fed. Cir. 2023) (empha-
sis added), but also that “all limitations of a claim must be
considered in deciding what invention is defined,” Hall v.
Taylor, 332 F.2d 844, 848 (CCPA 1964) (per Rich, J.); see
also Warner-Jenkinson Co. v. Hilton Davis Chemical Co.,
520 U.S. 17, 29 (1997) (“Each element contained in a patent
claim is deemed material to defining the scope of the pa-
tented invention.”). In this context, as in other legal-inter-
pretation settings, later text must be read along with
earlier text to discern the meaning. Cf. Arkansas Game
and Fish Commission v. United States, 568 U.S. 23, 36
(2014) (“But the first rule of case law as well as statutory
interpretation is: Read on.”).
The placement of the two requirements does not create
an otherwise-nonexistent contradiction. That is so even if
there was a more artful way of stating the two require-
ments within the same claim. And the record provides a
readily discernible explanation for the placement: The
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MAXELL, LTD. v. AMPEREX TECHNOLOGY LIMITED 8
second requirement for the M1 term was added during
prosecution to overcome a prior art reference that primar-
ily used nickel as a transition metal. See J.A. 1272–80,
1293–99. That there were other ways of drafting the claim
does not render the claim language contradictory or indef-
inite.
The district court’s explanation for its contrary conclu-
sion repeatedly describes limitation [c] as granting “op-
tions” as to the makeup of M1—seemingly in the sense of a
grant of right to others—which limitation [f] then takes
back. See Claim Construction Order, at *19–21. But this
description is inapt, even aside from its treatment of the
limitations in isolation from each other. Claim limitations
do not grant options. They state requirements—conditions
that must be met for a product or process (as the case may
be) to come within the claim’s protected zone of exclusivity.
If there are two requirements, and it is possible to meet
both, there is no contradiction.
That there is no contradiction here is confirmed by the
fact that it is the ordinary role of dependent claims to add
narrowing limitations to the independent claims to which
they refer. See, e.g., Alcon Research, Ltd. v. Apotex Inc.,
687 F.3d 1362, 1367 (Fed. Cir. 2012) (noting that “a de-
pendent claim narrows the claim from which it depends”).
If a limitation that merely narrows an earlier limitation
creates an invalidating contradiction, the ordinary practice
for dependent claims would be upended because, by stat-
ute, “[a] claim in dependent form shall be construed to in-
corporate by reference all the limitations of the claim to
which it refers.” 35 U.S.C. § 112 ¶ 4 (2006); 35 U.S.C.
§ 112(d). We recognized that narrowing does not imply
contradiction when we observed that “[a] dependent claim
that contradicts, rather than narrows, the claim from
which it depends is invalid.” Multilayer Stretch Cling Film
Holdings, Inc. v. Berry Plastics Corp., 831 F.3d 1350, 1362
(Fed. Cir. 2016) (emphasis added). Amperex itself properly
concedes that there would be no contradiction, and there-
fore no indefiniteness problem, if limitation [f] were recited
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MAXELL, LTD. v. AMPEREX TECHNOLOGY LIMITED 9
in a dependent claim, rather than in independent claim 1
itself. Oral Arg. at 15:45–17:04. But there is no difference
material to the indefiniteness inquiry between a narrowing
limitation recited in a dependent claim and the situation
here, where the further narrowing limitation is recited in
the independent claim itself.
Amperex, in support of its position, notes the contrast
between the claim language defining M1 and the claim lan-
guage defining the M2 term, which clearly requires magne-
sium. ’035 patent, col. 29, lines 33–35 (“M2 represents Mg
and at least one metal element selected from the group con-
sisting of Ti, Zr, Ge, Nb, Al, and Sn.”). The suggestion
seems to be that a relevant artisan would be irremediably
uncertain about the scope of M1 because if the patentee
truly meant to cover a cobalt-requiring M1, it would have
written the claim by using the language defining M2. But
this suggestion in no way establishes a contradiction,
which was the district court’s sole basis for holding the
claim indefinite. And it lacks merit on its own terms. The
language defining M1 is clear, and it is not overridden by
the specification or prosecution history. A relevant reader
would not reasonably be confused into abandoning that
clear meaning by the claim’s use of different language for
defining M2. That is especially so because the composi-
tional mixes of the two elements are different: M1 can be
100% cobalt, whereas M2 requires both magnesium and an-
other metal element (from the six-member group). One
would not expect simple borrowing of the M2 claim-lan-
guage formulation for M1.
III
The district court’s indefiniteness ruling and partial fi-
nal judgment are reversed and the matter is remanded for
further proceedings consistent with this opinion.
Costs awarded to appellant.
REVERSED AND REMANDED
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