United States Court of Appeals
for the Federal Circuit
__________________________
AIA ENGINEERING LIMITED,
Plaintiff/Counterclaim Defendant-Appellee,
AND
VEGA INDUSTRIES, LTD., INC.,
Third Party Defendant-Appellee,
v.
MAGOTTEAUX INTERNATIONAL S/A
AND MAGOTTEAUX, INC.,
Defendants/Counterclaim Plaintiffs-Appellants.
__________________________
2011-1058
__________________________
Appeal from the United States District Court for the
Middle District of Tennessee in Case No. 09-CV-0255,
Judge William J. Haynes, Jr.
__________________________
Decided: August 31, 2011
__________________________
DAVID LIEBERWORTH, Garvey Schubert Barer, of Seat-
tle, Washington, argued for plaintiff/counterclaim defen-
dant-appellee. With him on the brief was JARED VAN
KIRK.
AIA ENGINEERING v. MAGOTTEAUX INTL 2
ROBERT S. RIGG, Vedder Price P.C., of Chicago, Illi-
nois, argued for defendants/counterclaim plaintiffs-
appellants. With him on the brief were JOHN J. GRESENS
and WILLIAM J. VOLLER III.
__________________________
Before RADER, Chief Judge, and LOURIE and BRYSON,
Circuit Judges.
LOURIE, Circuit Judge.
Magotteaux International S/A and Magotteaux, Inc.,
(together, “Magotteaux”) appeal from the holding of the
United States District Court for the Middle District of
Tennessee on summary judgment that the asserted claims
of U.S. Patent RE39,998 (the “RE’998 patent”) are invalid
under 35 U.S.C. § 251 for impermissibly recapturing
subject matter surrendered during reissue examination.
AIA Eng’g Ltd. v. Magotteaux Int’l S/A, 745 F. Supp. 2d
852 (M.D. Tenn. 2010) (“SJ Op.”). Because the district
court erred in construing the claim term “solid solution,”
and thus erred in determining that the reissued claims
impermissibly recaptured surrendered subject matter, we
reverse and remand.
BACKGROUND
I
The patented technology in this case involves compos-
ite wear products used for crushing and grinding abrasive
materials in industrial settings. Magotteaux manufac-
tures composite wear products for grinding rock and other
abrasive materials and sells those products to power
stations and customers in the cement, mining, and recy-
cling industries. SJ Op. at 855. Magotteaux also owns
the RE’998 patent, a reissue of Magotteaux’s earlier U.S.
Patent 6,399,176 (the “’176 patent”). Entitled “Composite
3 AIA ENGINEERING v. MAGOTTEAUX INTL
Wear Component,” the RE’998 patent is directed to a
wear component that contains ceramic materials with a
mixture of aluminum oxide (alumina or Al2O3) and zirco-
nium oxide (zirconia or ZrO2). Id. at 856.
The district court’s opinion describes at length the
prosecution histories of the RE’998 and ’176 patents. See
id. at 856-62. We summarize them here only as relevant
to the dispute on appeal. The ’176 patent issued from an
application filed in the United States Patent and Trade-
mark Office (“PTO”) on June 1, 1999, which itself was a
national stage of a PCT application, 35 U.S.C. § 371, that
claimed priority from two European applications. J.A.
1365. In the original application received in the PTO,
independent claim 1 claimed a “[c]omposite wear compo-
nent” containing “inserts” that consist of a “ceramic pad,”
wherein the ceramic pad consists of “a homogeneous solid
solution of 20 to 80 % of Al2O3 and 80 to 20 % of ZrO2.”
J.A. 345. 1 The claim further required that the ceramic
pad “be[] impregnated with a liquid metal” during the
production process. Id. The examiner initially rejected
the pending claims as either anticipated under 35 U.S.C.
§ 102(b) by U.S. Patent 5,551,963 (“Larmie”) or obvious
under 35 U.S.C. § 103(a) over Larmie in view of other
1 As filed, claim 1 read as follows:
1. Composite wear component produced by
classical or centrifugal casting and consisting of a
metal matrix whose working face or faces include
inserts which have a very high wear resistance,
characterized in that the inserts consist of a ce-
ramic pad, this ceramic pad consisting of a homo-
geneous solid solution of 20 to 80 % of Al2O3 and
80 to 20 % of ZrO2, the percentages being ex-
pressed by weights of the constituents, and the
pad then being impregnated with a liquid metal
during the casting.
J.A. 345 (emphasis added).
AIA ENGINEERING v. MAGOTTEAUX INTL 4
prior art references. J.A. 323-30. In response, the appli-
cant submitted an amendment with remarks. J.A. 335-
65. The applicant amended independent claim 1 to spec-
ify, inter alia, that the ceramic pad was “porous,” but the
applicant did not alter the portion of the claim requiring a
“homogeneous solid solution.” 2 In addition, the applicant
disputed the examiner’s rejection over Larmie, arguing
that instead of using “liquid metal” during the production
process, Larmie merely taught the use of a “solution of . . .
salts of a metal.” J.A. 339. With respect to the “solid
solution” limitation of the pending claims, the applicant
stated that “the invention is based on the observation that
the ceramic pad must be a homogenous solid solution of
Al2O3/ZrO2.” J.A. 340.
The applicant also submitted a declaration under 37
C.F.R. § 1.132 by the application’s sole named inventor,
Hubert Jacques Francois. J.A. 358-61. In characterizing
his claimed invention, Francois used the term “solid
solution” several times, stating, for instance, that a “ho-
mogeneous solid solution of both ceramics meets the
advantages of both Al2O3 and ZrO2”; that “[a]n unexpected
synergy is the result of this solid solution which exhibits
better results than each single component contribution”;
2 As amended, claim 1 read as follows:
1. Composite wear component produced by
classical or centrifugal casting and consisting of
a metal matrix having a working face or faces
including inserts which have wear resistance, the
inserts consist of a porous ceramic pad, the porous
ceramic pad consisting of a homogenous solid solu-
tion of 20 to 80 % of Al2O3 and 80 to 20 % of ZrO2,
the percentages being expressed by weights of the
constituents, and the porous ceramic pad being in-
tegrated into the metal matrix by impregnation of
a liquid metal in the porous ceramic pad during
the casting.
J.A. 336 (emphasis added).
5 AIA ENGINEERING v. MAGOTTEAUX INTL
and that “[o]nly solid solutions of Al2O3 / ZrO2 in propor-
tions of 80/20 to 20/80 presents [sic] no ‘microspalling’
effects.” J.A. 359 (emphases added).
Following the applicant’s response to the office action,
the examiner issued a notice of allowance for claims 1-11.
J.A. 370. The ’176 patent issued on June 4, 2002, with
issued claim 1 reading as follows:
1. Composite wear component produced by
classical or centrifugal casting and consisting of
a metal matrix having a working face or faces
including inserts which have wear resistance, the
inserts consist of a porous ceramic pad, the porous
ceramic pad consisting of a homogeneous solid so-
lution of 20 to 80% of Al2O3 and 80 to 20% of ZrO2,
the percentages being expressed by weights of the
constituents, and the porous ceramic pad being in-
tegrated into the metal matrix by impregnation of
a liquid metal in the porous ceramic pad during
the casting.
’176 patent claim 1 (emphases added).
On May 30, 2003, the applicant, with the consent of
assignee Magotteaux, applied for reissue of the ’176
patent. J.A. 392-415. Through reissue the applicant
sought to amend claim 1 and to add new claims 12-21. SJ
Op. at 858. Both amended claim 1 and new independent
claim 12 were directed to a composite wear component.
Id. at 859. Claims 1 and 12 both replaced the term “solid
solution” in issued claim 1 with “ceramic composite.” J.A.
520-21. Moreover, new claim 12 used the terms “compris-
ing” and “comprises” instead of “consisting of” in specify-
ing the makeup of the wear component and the ceramic
pad. The examiner never objected to these new claim
AIA ENGINEERING v. MAGOTTEAUX INTL 6
limitations. See J.A. 447-51, 460-62, 470-80, 516, 533-42,
1326-34.
During prosecution of the RE’998 patent, an anony-
mous party filed a protest under 37 C.F.R. § 291, contend-
ing that claims 1 and 12 of the reissue application should
be rejected under 35 U.S.C. § 251. SJ Op. at 860; J.A.
1277-89. Specifically, the protestor asserted that the
substitutions in the reissue claims of (1) “comprises” for
“consisting of” and (2) “ceramic composite” for “solid
solution” impermissibly recaptured subject matter that
was surrendered during prosecution of the original ’176
patent. The examiner disagreed with the protestor and
found that the reissue claims did not violate § 251. SJ
Op. at 860; J.A. 1330-31. Regarding the first substitution,
the examiner concluded that the applicant’s submissions
during prosecution of the ’176 patent did not limit the
ceramic pads to only Al2O3 and ZrO2 and that “the specifi-
cation clearly teaches that other additives in addition to
the claimed compounds may be included in the compos-
ite.” J.A. 1331. As for the second substitution, the exam-
iner acknowledged that the applicant referred to the
invention as a solid solution during prosecution, but
stated that, upon review of the specification and its dis-
closed method of forming the composite, “it is unclear how
Applicant’s reference to this composite as a ‘solid solution’
would somehow limit the scope of the claims from any
other combination of the claimed materials.” J.A. 1330-
31.
The RE’998 patent issued on January 8, 2008, and a
certificate of correction issued shortly thereafter to correct
7 AIA ENGINEERING v. MAGOTTEAUX INTL
certain claim language. 3 J.A. 1365, 1373. Claims 1 and
12 of the RE’998 patent, as corrected, read as follows:
1. Composite wear component produced by
classical or centrifugal casting and consisting of a
metal matrix having a working face or faces in-
cluding inserts which have wear resistance,
wherein the inserts consist of a porous ceramic
pad, the porous ceramic pad consisting of a homo-
geneous ceramic composite of 20 to 80% of Al2O3
and 80 to 20% of ZrO2, the percentages being ex-
pressed by weights of the constituents, and the
porous ceramic pad being integrated into the
metal matrix by impregnation of a liquid metal in
the porous ceramic pad during the casting.
12. Composite wear component produced by
classical or centrifugal casting, said composite
wear component comprising a metal matrix hav-
ing a working face or faces including inserts which
have wear resistance, the inserts include a porous
ceramic pad, wherein the porous ceramic pad com-
prises a homogeneous ceramic composite [of] 20 to
80% of Al2O3 and 80 to 20% of ZrO2, the percent-
ages being expressed by weights of the constitu-
ents, and the porous ceramic pad being integrated
into the metal matrix by impregnation of a liquid
metal in the porous ceramic pad during the cast-
ing.
RE’998 patent claims 1, 12 (emphases added); SJ Op. at
862.
3 For purposes of this appeal, the written descrip-
tion portions of the ’176 and RE’998 patents contain no
material differences.
AIA ENGINEERING v. MAGOTTEAUX INTL 8
II
On March 16, 2009, AIA Engineering sued Magot-
teaux in the United States District Court for the Middle
District of Tennessee for a declaratory judgment of nonin-
fringement, invalidity, and unenforceability of the RE’998
patent. As alleged in its complaint, AIA Engineering
designs, develops, manufactures, installs, and services
wear-, corrosion-, and abrasion-resistant products for the
cement, mining, and thermal power generation industries.
Compl. at 4; see also SJ Op. at 854-55. Magotteaux then
filed a third-party complaint against Vega Industries, a
subsidiary of AIA Engineering, alleging infringement of
the RE’998 patent. The court held a claim construction
hearing on the disputed claim terms in November 2009.
AIA Engineering and Vega Industries (together, “AIA”)
then moved for summary judgment of invalidity, arguing
that the claims of Magotteaux’s RE’998 patent improperly
recaptured subject matter surrendered during the prose-
cution of its earlier ’176 patent.
In a memorandum opinion dated September 3, 2010,
the district court granted summary judgment in favor of
AIA. SJ Op. at 875-86. The court detailed the prosecu-
tion histories of the ’176 and RE’998 patents, summarized
above, and described the patented technology. Id. at 856-
62. The court found that the process for preparing Magot-
teaux’s composite wear component begins by “combin[ing]
or mix[ing] Al2O3 and ZrO2 into composite ceramic
grains,” which are manufactured by a process that “al-
low[s] the two constituent chemicals to fuse.” Id. at 859.
The court clarified, however, that “[o]nce combined, the
Al2O3 and ZrO2 retain their crystal structure.” Id. As the
court found, the porous ceramic pad is then “formed by
pouring the composite ceramic grains and an adhesive
into a mold to hold the ceramic grains together,” where-
9 AIA ENGINEERING v. MAGOTTEAUX INTL
upon “liquid metal is impregnated in the pad during
casting to form the final composite wear component.” Id.
To determine whether Magotteaux broadened claim
scope during reissue, the district court reviewed the
parties’ claim construction arguments. The court con-
cluded that, in the ’176 patent, “‘homogeneous solid
solution’ in claim 1 and the related specification means
that its composition is limited to ‘20 to 80% of Al2O3 and
80 to 20% of ZrO2, the percentages being expressed by
weights of the constituents,’ with no other solute present
in the solid solution.” Id. at 870. The court then turned
to the parties’ arguments concerning the term “homoge-
neous ceramic composite” in the RE’998 patent, but, as we
discuss below, the court did not explicitly construe this
term. Id. at 870-73. Nevertheless, the court held that the
substitution of “ceramic composite” in claims 1 and 12 of
the RE’998 patent for “solid solution” in claim 1 of the
’176 patent broadened the scope of the reissue claims. Id.
at 873. Finally, citing Vehicular Technologies Corp. v.
Titan Wheel International, Inc., 212 F.3d 1377, 1382-83
(Fed. Cir. 2000), the court noted that the term “consisting
of” (as in claim 1 of the ’176 patent) signifies restriction
and exclusion, whereas “comprising” (as in claim 12 of the
RE’998 patent) indicates an open-ended construction, and
the court thus found broadening in this aspect as well. SJ
Op. at 870, 873.
Having found the reissued claims broadened, the dis-
trict court turned to the issue of recapture. With respect
to claims 1 and 12 of the RE’998 patent, the court held
that Magotteaux relied on the “solid solution” limitation
to overcome prior art during prosecution of the ’176
patent and thus surrendered broader scope to a “ceramic
AIA ENGINEERING v. MAGOTTEAUX INTL 10
composite.” Id. at 875. 4 The court thus held that the two
independent claims in the RE’998 patent are invalid for
violating the rule against recapture under 35 U.S.C.
§ 251. Id. at 875-86.
Magotteaux timely appealed from the district court’s
final judgment. We have jurisdiction pursuant to 28
U.S.C. § 1295(a)(1).
DISCUSSION
We review a district court’s grant of summary judg-
ment de novo, applying the same standard as the district
court and drawing all reasonable inferences in favor of the
nonmovant. Anderson v. Liberty Lobby, Inc., 477 U.S.
242, 255 (1986). Summary judgment is appropriate “if the
movant shows that there is no genuine dispute as to any
material fact and the movant is entitled to judgment as a
matter of law.” Fed. R. Civ. P. 56. Determining whether
the claims of a reissue patent violate 35 U.S.C. § 251 is a
question of law, which we review de novo. Pannu v. Storz
Instruments, Inc., 258 F.3d 1366, 1370 (Fed. Cir. 2001).
Whether a claim amendment during reissue examination
enlarged the scope of the claim is a matter of claim con-
struction. Medtronic, Inc. v. Guidant Corp., 465 F.3d
1360, 1374 (Fed. Cir. 2006). Claim construction is a
question of law that we review without deference. Cybor
Corp. v. FAS Techs., Inc., 138 F.3d 1448, 1456 (Fed. Cir.
1998) (en banc). Likewise, comparing the scope of the
claims of an original patent and a reissue patent is a legal
question subject to de novo review. Westvaco Corp. v. Int’l
Paper Co., 991 F.2d 735, 741 (Fed. Cir. 1993).
4 Although the district court discussed the amend-
ment of “consisting of” to “comprises” in the recapture
portion of its opinion, it is unclear whether the court
found this amendment to recapture surrendered subject
matter. See SJ Op. at 875.
11 AIA ENGINEERING v. MAGOTTEAUX INTL
As we explain below, we hold that the RE’998 patent
does not violate the rule against recapture under § 251
and that the district court erred by granting summary
judgment of invalidity on this basis. In particular, we
conclude that the district court legally erred in its con-
struction of “homogeneous solid solution,” and that,
correctly construed, this term is synonymous with “homo-
geneous ceramic composite” in the patents at issue.
Accordingly, there was no recapture with respect to this
amendment. Further, the parties do not dispute that the
amendment of “consisting of” to “comprising,” although
broadening, does not recapture surrendered subject
matter here. The district court thus erred by invalidating
the RE’998 patent under § 251.
I
A party accused of infringing a reissued patent may
assert as an affirmative defense the failure of the pat-
entee to comply with 35 U.S.C. § 251. See 35 U.S.C. § 282
(2006). Under § 251, a patentee may obtain reissue of a
patent if that patent is, “through error without any decep-
tive intention, deemed wholly or partly inoperative or
invalid, . . . by reason of the patentee claiming more or
less than he had a right to claim in the patent . . . .” Id.
§ 251. If proposed within two years from the grant of the
patent, the reissue may broaden the scope of the claims.
In re Graff, 111 F.3d 874, 877 (Fed. Cir. 1997). Notwith-
standing the limited ability to enlarge claim scope
through reissue, the recapture rule prevents a patentee
from regaining subject matter deliberately surrendered
during the prosecution of the original patent. Pannu, 258
F.3d at 1370-71.
To invalidate a patent claim for recapture, “[t]he chal-
lenger of the reissued patent . . . must establish surrender
of recaptured subject matter by clear and convincing
AIA ENGINEERING v. MAGOTTEAUX INTL 12
evidence.” Kim v. ConAgra Foods, Inc., 465 F.3d 1312,
1322 (Fed. Cir. 2006); see also Microsoft Corp. v. i4i Ltd.,
131 S. Ct. 2238, 2242 (2011). A three-step test guides the
analysis:
(1) first, we determine whether, and in what re-
spect, the reissue claims are broader in scope than
the original patent claims; (2) next, we determine
whether the broader aspects of the reissue claims
relate to subject matter surrendered in the origi-
nal prosecution; and (3) finally, we determine
whether the reissue claims were materially nar-
rowed in other respects, so that the claims may
not have been enlarged, and hence avoid the re-
capture rule.
Medtronic, 465 F.3d at 1373.
The first step of the recapture test requires the appli-
cation of claim construction principles to determine
whether and in what aspect the reissue claims are
broader than the original claims. Id. at 1374. To ascer-
tain the scope and meaning of a claim, we consider the
claim language, the specification, the prosecution history,
and the relevant extrinsic evidence. Phillips v. AWH
Corp., 415 F.3d 1303, 1314-17 (Fed. Cir. 2005) (en banc).
Apart from the claim language itself, “the specification is
the single best guide to the meaning of a claim term.”
Curtiss-Wright Flow Control Corp. v. Velan, Inc., 438 F.3d
1374, 1378 (Fed. Cir. 2006). The prosecution history, in
contrast, “often lacks the clarity of the specification and
thus is less useful for claim construction purposes.”
Phillips, 415 F.3d at 1317. Nevertheless, the prosecution
history may “demonstrat[e] how the inventor understood
the invention and whether the inventor limited the inven-
tion in the course of prosecution.” Id.
13 AIA ENGINEERING v. MAGOTTEAUX INTL
Extrinsic evidence, which includes expert and inven-
tor testimony, dictionaries, and learned treatises, may
“‘aid the court in coming to a correct conclusion’ as to the
‘true meaning of the language employed’ in the patent.”
Markman v. Westview Instruments, Inc., 52 F.3d 967, 980
(Fed. Cir. 1995) (en banc) (quoting Seymour v. Osborne, 78
U.S. 516, 546 (1870)). We generally view extrinsic evi-
dence as “less reliable than the patent and its prosecution
history in determining how to read claim terms.” Phillips,
415 F.3d at 1318. Nevertheless, extrinsic evidence in the
form of expert testimony can be useful “for a variety of
purposes, such as to provide background on the technol-
ogy at issue, to explain how an invention works, [or] to
ensure that the court’s understanding of the technical
aspects of the patent is consistent with that of a person of
skill in the art.” Id.
The district court concluded that replacing “homoge-
neous solid solution” in original claim 1 with “homogene-
ous ceramic composite” in reissue claims 1 and 12
broadened the scope of the reissue claims. For the follow-
ing reasons, we disagree.
We first consider the term “homogeneous ceramic
composite” in claims 1 and 12 of the RE’998 patent. The
district court’s handling of this term is a source of some
confusion among the parties on appeal. The court’s
opinion first noted the parties’ differing proposed con-
structions and then proceeded to discuss, almost exclu-
sively, Magotteaux’s proposed constructions for
“homogeneous,” “composite,” “ceramic composite,” and
“homogeneous ceramic composite.” SJ Op. at 870-73
(noting that Magotteaux offered a total of five construc-
tions for these terms, including two different construc-
tions for “ceramic composite”). Despite the various
constructions proposed by the parties, however, the court
AIA ENGINEERING v. MAGOTTEAUX INTL 14
never explicitly adopted a single construction for this
term. Id.
On appeal, Magotteaux argues that the district court’s
recapture analysis was fundamentally flawed because the
court failed to construe “homogeneous ceramic composite.”
Magotteaux proposes the following construction for this
claim term: “an aggregation of relatively consistent
grains of at least Al2O3 and ZrO2 wherein each of the
Al2O3 and ZrO2 retains a distinct composition and/or
crystal structure.” Magotteaux Opening Br. 24. That
construction, Magotteaux argues, is supported by the
claim language, the written description, and the prosecu-
tion history of the RE’998 patent.
In response, AIA does not propose a construction for
“homogeneous ceramic composite.” Rather, AIA contends
that the district court correctly (albeit implicitly) adopted
Magotteaux’s proposed construction below. Yet AIA fails
to identify which of Magotteaux’s several constructions
the court in fact adopted. AIA Br. 45 (contending only
that the district court “adopt[ed] through its analysis
Magotteaux’s proposed definition(s) for the phrase ‘homo-
geneous ceramic composite’ in the claims” (emphasis
added)). Nevertheless, AIA appears to allege that the
construction proposed by Magotteaux on appeal is incon-
sistent with Magotteaux’s earlier proposed constructions.
Reviewing de novo the district court’s claim construc-
tion analysis and the parties’ arguments, we agree with
the construction proposed by Magotteaux on appeal, and
we hold that “homogeneous ceramic composite” means “an
aggregation of relatively consistent grains of at least
Al2O3 and ZrO2, wherein each of the Al2O3 and ZrO2
retains a distinct composition and/or crystal structure.”
As an initial matter, we note that the construction pro-
posed by Magotteaux on appeal is consistent with the
15 AIA ENGINEERING v. MAGOTTEAUX INTL
constructions it proposed to the district court. For exam-
ple, at the district court, Magotteaux asserted that “ho-
mogeneous ceramic composite” means “[a]n aggregation of
relatively consistent grains of at least 20 to 80% of Al2O3
and 80 to 20% of ZrO2” and that “ceramic composite”
means “the mixture of at least Al2O3 and ZrO2, wherein
each of the Al2O3 and ZrO2 retains a distinct composition
and/or crystal structure.” SJ Op. at 871-72. To the extent
that AIA disagrees with Magotteaux’s construction, we
note that AIA declined on appeal to offer any construction
for this term.
Magotteaux’s construction is supported by the claims,
written description, and prosecution history of the RE’998
patent. Claims 1 and 12 of the RE’998 patent require “a
homogeneous ceramic composite of 20 to 80% of Al2O3 and
80 to 20% of ZrO2,” indicating that the composite must
contain Al2O3 and ZrO2—both of which are ceramics. The
specification describes the ceramic material that makes
up the claimed ceramic pad as both “homogeneous” and
“composite.” RE’998 patent col.2 ll.61-65 (describing the
claimed inserts as “being made of a ceramic material,
itself composite, consisting of a solid solution or homoge-
neous phase of 20 to 80% of Al2O3 and 80 to 20% [of] ZrO2”
(emphases added)). The RE’998 patent also discloses that
“[t]his composite ceramic material is produced from an
aggregate of ceramic grains” that are formed by “allowing
the two constituents [i.e., alumina and zirconia] to fuse.”
Id. col.3 ll.23-30 (emphases added). In describing “the
zirconium particles present in the alumina” within the
ceramic pads, the specification is clear that, although they
are fused together, the Al2O3 and ZrO2 particles remain
distinct in the ceramic composite. Id. col.3 ll.57-58 (em-
phasis added).
The prosecution history does not alter the meaning of
“homogeneous ceramic composite” provided by the claims
AIA ENGINEERING v. MAGOTTEAUX INTL 16
and specification. The scope or meaning of this term was
not addressed during prosecution, and the parties do not
argue otherwise on appeal.
Finally, the parties’ scientific experts confirm that the
teachings of the specification support Magotteaux’s pro-
posed claim construction. Dr. Andreas Glaeser, AIA’s
expert, cited an introductory materials science and engi-
neering textbook as evidence that a person skilled in the
art at the time of the invention would have understood
“composite” to mean “a material that is a mixture or
combination of two or more materials, each of which has
and retains a distinct composition and/or crystal struc-
ture.” Report of Andreas M. Glaeser at 1, AIA Eng’g Ltd.
v. Magotteaux Int’l S/A, No. 09-cv-255 (ECF No. 52-5)
(Sept. 11, 2009) (emphasis added) (citing William D.
Callister, Materials Science and Engineering: An Intro-
duction 514 (3d ed. 1994)). On appeal, AIA references the
same textbook, conceding that “there is at least some
external evidence that a ‘composite’ could be generally
viewed as a ‘multiphase material’” and that “[t]his extrin-
sic definition is consistent with Magotteaux’s contention
that a ‘homogeneous ceramic composite’ is a mixture in
which the constituent materials retain their own distinct
crystalline structure.” AIA Br. 46 n.8 (second emphasis
added).
Magotteaux’s expert, Dr. Katherine Faber, declared
that “[a] composite is comprised of two or more substances
that are physically and chemically differentiable” and
noted that this definition is “substantially identical” to
the construction offered by Dr. Glaeser. J.A. 2463-64. Dr.
Faber further explained that the statement in the specifi-
cation regarding “‘the zirconium [oxide] particles present
in the alumina’” indicates that “zirconium oxide is not
mixed at the atomic level in the solid, . . . but at the
particle level (at least hundreds of atoms) consistent with
17 AIA ENGINEERING v. MAGOTTEAUX INTL
Dr. Glaeser’s and my understanding of composite.” J.A.
2464.
In light of the claims, written description, and prose-
cution history of the RE’998 patent, as well as the rele-
vant expert testimony, we construe “homogeneous
ceramic composite” as “an aggregation of relatively consis-
tent grains of at least Al2O3 and ZrO2, wherein each of the
Al2O3 and ZrO2 retains a distinct composition and/or
crystal structure.”
We next consider the meaning of “homogeneous solid
solution” in claim 1 of the ’176 patent. As noted above,
the district court construed this term as a “composition
. . . limited to ‘20 to 80% of Al2O3 and 80 to 20% of ZrO2,
the percentages being expressed by weights of the con-
stituents,’ with no other solute present in the solid solu-
tion.” 5 SJ Op. at 870.
Magotteaux argues that the district court erred by ig-
noring the intrinsic evidence and adopting an extrinsic
definition from a trade treatise proffered by AIA. Magot-
teaux asserts that the district court disregarded the fact
that it is impossible to make an alumina-zirconia solid
solution, as defined by the district court, in the claimed
range of compositions. Magotteaux further asserts that
the district court’s construction of this term directly
contradicts its determination that, once combined, Al2O3
and ZrO2 retain their crystal structure. Magotteaux
maintains that, properly construed, “homogeneous solid
solution” is synonymous with “homogeneous ceramic
5 That construction was similar, but not identical,
to the construction proposed by AIA to the district court:
“a mixture of two or more types of molecules or atoms in
the solid state wherein the minor component, the solute,
is incorporated into the major component, the solvent, and
the crystal structure of the solvent is maintained as the
concentration of the solute is increased.” J.A. 1405.
AIA ENGINEERING v. MAGOTTEAUX INTL 18
composite.” This meaning, according to Magotteaux, is
supported by the claim language, the specification, and
the prosecution histories of the ’176 and RE’998 patents.
In response, AIA contends that the district court cor-
rectly recognized that a “homogeneous solid solution” is
characterized by a solute in solution, arguing that the
correct construction of this term is “a mixture of a solute
or solutes into a solvent in which the materials maintain
the single, uniform crystalline structure of the solvent.”
AIA Br. 31-32. According to AIA, the claims, specifica-
tion, and prosecution history support this construction.
AIA also contends that extrinsic evidence, in the form of
numerous technical treatises, demonstrates that a skilled
person would have understood the ordinary meaning of
“solid solution” to require a single, uniform crystalline
structure. AIA further contends that, contrary to Magot-
teaux’s assertions, solid solutions of alumina and zirconia
can be formed.
We agree with Magotteaux that these two terms, as
used in the ’176 and RE’998 patents, are synonymous.
Initially, we note that Magotteaux and AIA agree that the
ordinary meaning of “solid solution” requires a single,
uniform structure containing both a “solvent” component
and a “solute” component, in which the solvent component
dictates the overall structure of the solid. See SJ Op. at
864; see also AIA Br. 42; Magotteaux Opening Br. 26-28.
Further, according to the technical treatise cited by AIA
and quoted by the district court, there are generally two
types of solid solutions, but it is not necessarily possible to
form either type of solid solution from two given chemical
substances. 6 SJ Op. at 864.
6 As the treatise explains, an “interstitial” solid so-
lution, in which the solute is positioned in the interstitial
sites formed by the solvent, “is possible only when the
19 AIA ENGINEERING v. MAGOTTEAUX INTL
While the parties agree on the ordinary meaning of
“solid solution,” they dispute the physical form of the
alumina-zirconia material required by the “solid solution”
of claim 1 of the ’176 patent. AIA, in accordance with the
district court’s construction, seeks to apply the ordinary
meaning of “solid solution” involving a solute in a solvent
with a single, uniform structure. Magotteaux, on the
other hand, urges that the patentee acted as his own
lexicographer and employed a special definition for “solid
solution”—i.e., used it as a synonym for “homogeneous
ceramic composite.”
We have recognized that “the specification may reveal
a special definition given to a claim term by the patentee
that differs from the meaning it would otherwise possess.”
Phillips, 415 F.3d at 1316. In such cases, “the inventor’s
lexicography governs.” Id. Moreover, “[t]he specification
need not reveal such a definition explicitly,” but may do so
“by implication.” Astrazeneca LP v. Apotex, Inc., 633 F.3d
1042, 1051-52 (Fed. Cir. 2010) (internal quotation marks
omitted).
In this case, the intrinsic evidence reveals that the
patentee acted as his own lexicographer and used “homo-
geneous solid solution” as a synonym for “homogeneous
ceramic composite.” With respect to the claim language,
claim 1 of the ’176 patent requires a “homogeneous solid
solution of 20 to 80% of Al2O3 and 80 to 20% of ZrO2,”
which, like the “homogeneous ceramic composite” of
claims 1 and 12 of the RE’998 patent, requires both Al2O3
and ZrO2 in the same claimed proportions. As for the
written description portion of the specification, the only
solvent . . . is much larger compared to the solute.” SJ
Op. at 864. A “substitutional” solid solution, in which the
solute replaces the solvent at specific sites in the solid, “is
only possible[] if both the [solute and solvent] are similar
in size and also in nature.” Id.
AIA ENGINEERING v. MAGOTTEAUX INTL 20
instance of “solid solution” states that the “inserts” in the
“composite wear component” are “made of a ceramic
material, itself composite, consisting of a solid solution or
homogeneous phase of 20 to 80% of Al2O3 and 80 to 20% of
ZrO2.” ’176 patent col.2 ll.53-62 (emphases added).
A composite, as noted above, is a mixture in which the
constituent materials retain their own distinct crystalline
structures. Yet the ordinary meaning of “solid solution,”
the parties agree, requires a single, uniform crystalline
structure. SJ Op. at 864; see also J.A. 1491, 1714. Thus,
rigidly confining “solid solution” to its ordinary meaning
gives rise to a contradiction in terms, such that a “ceramic
material, itself composite, consisting of a solid solution,”
’176 patent col.2 ll.58-59, would at once require two
distinct crystalline structures and a single, uniform
crystalline structure. We strive, where possible, to avoid
nonsensical results in construing claim language. Bd. of
Regents of the Univ. of Tex. Sys. v. BENQ Am. Corp., 533
F.3d 1362, 1370 (Fed. Cir. 2008) (“We decline to adopt a
construction that would effect this nonsensical result.”).
Construing “solid solution” as having the same meaning
as “ceramic composite” avoids this absurdity and confirms
that the specification teaches fused grains of Al2O3 and
ZrO2, each of which retains its crystal structure.
In addition to avoiding a nonsensical result, this con-
struction is also supported by the district court’s descrip-
tion of the nature of the claimed invention. As noted
above, the court determined that, “[o]nce combined, the
Al2O3 and ZrO2 retain their crystal structure.” SJ Op. at
859. This description of the invention, which would
require two distinct crystalline structures in the combined
material, is inconsistent with the ordinary meaning of
“solid solution.”
21 AIA ENGINEERING v. MAGOTTEAUX INTL
Furthermore, the parties do not seriously dispute that
the only method disclosed in the ’176 and RE’998 patents
for preparing the claimed ceramic pad involves forming a
ceramic composite, not a solid solution as that term is
conventionally defined. While we recognize that “there is
sometimes a fine line between reading a claim in light of
the specification, and reading a limitation into the claim
from the specification,” Decisioning.com, Inc. v. Federated
Department Stores, Inc., 527 F.3d 1300, 1307-08 (Fed. Cir.
2008) (internal quotation marks omitted), the fact that
the specification here does not teach any method of pre-
paring an alumina-zirconia solid solution with a single,
uniform crystal structure lends further credence to Ma-
gotteaux’s position that one of ordinary skill would recog-
nize that the inventor acted as his own lexicographer.
We disagree with the district court’s and AIA’s view of
the prosecution history as evincing a narrow definition for
“solid solution.” Consistent with the district court’s
reasoning, SJ Op. at 869-70, AIA emphasizes the number
of times during prosecution that Magotteaux recited the
term “solid solution.” AIA does not, however, identify any
instances in which Magotteaux expressly or implicitly
defined this term or qualified it to distinguish any of the
prior art references. For example, AIA notes that the
inventor stated in a declaration that a “homogeneous solid
solution of both ceramics meets the advantages of both
Al2O3 and ZrO2”; that “[a]n unexpected synergy is the
result of this solid solution which exhibits better results
than each single component contribution”; and that
“[o]nly solid solutions of Al2O3 / ZrO2 in proportions of
80/20 to 20/80 presents [sic] no ‘microspalling’ effects.”
J.A. 359 (emphases added). None of these statements
clarifies the meaning of “solid solution”; they are merely
examples of the applicant referring to his claimed inven-
tion using the same language as in the existing claims.
AIA ENGINEERING v. MAGOTTEAUX INTL 22
Indeed, as the PTO examiner observed in the RE’998
patent’s notice of allowance, “it is unclear how Applicant’s
reference to this composite as a ‘solid solution’ would
somehow limit the scope of the claims from any other
combination of the claimed materials.” J.A. 1330-31. We
conclude, contrary to the district court, that the applicant
did not disclaim any interpretations of “solid solution”
during prosecution and that, in this case, the prosecution
history is not particularly helpful in construing this term.
See Rhodia Chimie v. PPG Indus. Inc., 402 F.3d 1371,
1384 (Fed. Cir. 2005) (“The purpose of consulting the
prosecution history in construing a claim is to exclude any
interpretation that was disclaimed during prosecution.”
(internal quotation marks omitted)); Athletic Alternatives,
Inc. v. Prince Mfg., Inc., 73 F.3d 1573, 1580 (Fed. Cir.
1996) (“The prosecution in this case is thus unhelpful as
an interpretive resource . . . .”); see also Phillips, 415 F.3d
at 1317.
We may look to extrinsic evidence “to ensure that the
court’s understanding of the technical aspects of the
patent is consistent with that of a person of skill in the
art.” Phillips, 415 F.3d at 1318. In this case, in deter-
mining the meaning of “solid solution” as used in claim 1
of the ’176 patent, the extrinsic evidence of record is
particularly illuminating. Significantly, the parties’
experts agree that, under AIA’s proposed construction, an
alumina-zirconia solid solution as claimed in the ’176
patent is not physically possible. As noted, AIA asserts
that one of ordinary skill would understand that the
ordinary meaning of “solid solution” requires a single,
uniform crystalline structure containing both Al2O3 and
ZrO2. But Dr. Glaeser, AIA’s expert, explained that it was
known as of the ’176 patent’s priority date that, “[a]t
equilibrium, solid Al2O3 and solid ZrO2 do not share a
common crystal structure at any temperature.” J.A. 1558;
23 AIA ENGINEERING v. MAGOTTEAUX INTL
see also J.A. 1588 (“The equilibrium phase diagram, a
stability map that defines which phase(s) should be
present at a given temperature and system composition,
shows no solid solutions of Al2O3 and ZrO2 in the range of
composition that the Francois patent specifies.” (emphasis
omitted)). A crystalline material containing a mixture of
alumina and zirconia, Dr. Glaeser explained, “contains
two distinct phases. It is then not a solid solution. It is
also not a homogeneous solid solution.” J.A. 1558. More-
over, the impossibility of forming the claimed “solid
solution” would have been apparent to one of ordinary
skill: “The patent literature points out the difficulty of
achieving ‘homogeneous’ composites in the Al2O3-ZrO2
system when materials are formed by conventional solidi-
fication processes or by mixing of Al2O3 and ZrO2 pow-
ders.” Id. Dr. Faber, Magotteaux’s expert, agreed with
this assessment: “[I]t is accepted by persons with ordi-
nary skill in the art that from a thermodynamic stand-
point, Al2O3 and ZrO2 do not form a complete solid
solution.” J.A. 2463.
AIA’s proposed claim construction, therefore, requires
a material that its own expert admits is physically impos-
sible to produce. AIA nonetheless contends that its con-
struction would not render the invention inoperable,
because nonequilibrium “amorphous” solid solutions in
the claimed proportions of Al2O3 and ZrO2 can be pre-
pared. For support, it cites Dr. Glaeser’s report, which
stated that “[s]olid solutions (amorphous solids) within
the composition range defined by [the ’176 patent] have
been formed in the Al2O3-ZrO2 system.” J.A. 1558. Yet
those solids are amorphous, not crystalline as AIA’s claim
construction requires. See, e.g., J.A. 1589 (distinguishing
“amorphous” materials from “crystalline” materials).
Furthermore, even assuming AIA’s proposed construction
encompassed an amorphous solid solution, the viability of
AIA ENGINEERING v. MAGOTTEAUX INTL 24
such a solid solution remains dubious. As Dr. Glaeser
conceded, “it would be extremely difficult if not impossible
to produce amorphous ‘homogeneous solid solution’ parti-
cles of the size specified in the [’176] patent.” J.A. 1589.
While inoperability in itself does not doom AIA’s con-
struction, “a construction that renders the claimed inven-
tion inoperable should be viewed with extreme
skepticism.” Talbert Fuel Sys. Patents Co. v. Unocal
Corp., 275 F.3d 1371, 1376 (Fed. Cir. 2002), vacated and
remanded on other grounds, 537 U.S. 802 (2002); see also
Astrazeneca, 633 F.3d at 1053 n.1. Of course, “courts may
not redraft claims, whether to make them operable or to
sustain their validity.” Chef Am., Inc. v. Lamb-Weston,
Inc., 358 F.3d 1371, 1374 (Fed. Cir. 2004). But where, as
here, the specification reveals a special meaning for a
term that differs from the meaning it might otherwise
possess, that special meaning governs, particularly when
it also serves to avoid an inoperable claim construction.
Astrazeneca, 633 F.3d at 1051 (“‘[T]he specification may
reveal a special definition given to a claim term by the
patentee that differs from the meaning it would otherwise
possess. In such cases, the inventor’s lexicography gov-
erns.’” (quoting Phillips, 415 F.3d at 1316)); Bell Atl.
Network Servs., Inc. v. Covad Commc’ns Grp., Inc., 262
F.3d 1258, 1268 (Fed. Cir. 2001) (“[A] claim term may be
clearly redefined without an explicit statement of redefi-
nition.”).
Here, AIA relies on extrinsic evidence to prove that
one of ordinary skill would have known that “solid solu-
tion” has an ordinary and customary meaning in the art.
But that same extrinsic evidence also proves, as both
parties’ experts agree, that one of ordinary skill would
also have known that it is physically impossible to make a
“solid solution,” under that term’s ordinary meaning, as
claimed in the ’176 patent. Taken as a whole, therefore,
25 AIA ENGINEERING v. MAGOTTEAUX INTL
the extrinsic evidence demonstrates that although “solid
solution” has an ordinary meaning in the art, the pat-
entee here chose instead to apply a special meaning to the
term.
Finally, AIA urges us in construing “solid solution” to
consider evidence from corresponding foreign applica-
tions, including claim amendments in the European and
PCT priority applications and patentability statements in
the international preliminary examination report for the
corresponding PCT application. We have previously noted
that “the theories and laws of patentability vary from
country to country, as do examination practices.” Heidel-
berger Druckmaschinen AG v. Hantscho Commercial
Prods., Inc., 21 F.3d 1068, 1072 n.2 (Fed. Cir. 1994); see
also Lindemann Maschinenfabrik GMBH v. Am. Hoist &
Derrick Co., 730 F.2d 1452, 1458 n.2 (Fed. Cir. 1984)
(“[T]he language and laws of other countries differ sub-
stantially from those in the United States.”). For this
reason, we have noted “that ‘the varying legal and proce-
dural requirements for obtaining patent protection in
foreign countries might render consideration of certain
types of representations inappropriate’ for consideration
in a claim construction analysis of a United States coun-
terpart.” TI Grp. Auto. Sys. (N. Am.), Inc. v. VDO N. Am.,
L.L.C., 375 F.3d 1126, 1136 (Fed. Cir. 2004) (quoting
Caterpillar Tractor Co. v. Berco, S.p.A., 714 F.2d 1110,
1116 (Fed. Cir. 1983). Accordingly, despite AIA’s urgings,
our precedent cautions against indiscriminate reliance on
the prosecution of corresponding foreign applications in
the claim construction analysis. Here, even assuming
that the foreign claim amendments and patentability
statements were relevant to our claim construction analy-
sis, we find that evidence unpersuasive. We also note
that evidence proffered by AIA regarding statements in
the specification of one of the European priority applica-
AIA ENGINEERING v. MAGOTTEAUX INTL 26
tions is, at best, equivocal as to the meaning of “solid
solution”; it does not alter the clear import of the claim
language, specification, and relevant extrinsic evidence in
this case. See Abbott Labs. v. Sandoz, Inc., 566 F.3d 1282,
1290 (Fed. Cir. 2009).
We therefore hold that the district court’s claim con-
struction was erroneous. In light of the intrinsic and
extrinsic evidence of record, we conclude that the patentee
acted as his own lexicographer and that the claim terms
“homogeneous solid solution” and “homogeneous ceramic
composite” are synonymous in the context of the ’176 and
RE’998 patents. Accordingly, the reissue prosecution did
not broaden the claims in this aspect.
II
Applying the remainder of the recapture test in this
case is straightforward. Only if a reissued claim contains
“broader aspects” than the originally issued claim do we
consider the matter of surrender. Clement, 131 F.3d at
1468-69. Here, as noted, the reissue claims were not
broadened with respect to the substitution of “ceramic
composite” for “solid solution.” Because there was no
broadening in this aspect of the claims, there can be no
pertinent surrender.
Furthermore, while the parties agree with the district
court’s holding that the substitution of “comprises” and
“comprising” for “consisting of” in new reissued claim 12
(as compared to original claim 1) did broaden the claims
in this aspect, SJ Op. at 875, the parties also agree that
no subject matter was surrendered by this substitution.
Accordingly, we conclude that the test for impermissi-
ble recapture under 35 U.S.C. § 251 is not met, and that
the district court erred by granting AIA’s motion for
27 AIA ENGINEERING v. MAGOTTEAUX INTL
summary judgment and invalidating the reissued claims
of the RE’998 patent on this basis.
CONCLUSION
For the foregoing reasons, we reverse the district
court’s summary judgment of invalidity of the RE’998
patent under 35 U.S.C. § 251. We remand the case to the
district court for further proceedings.
REVERSED AND REMANDED
COSTS
Costs to Magotteaux.