Centricut v. Esab Group, et a l . CV-99-039-M 02/07/02 UNITED STATES DISTRICT COURT
DISTRICT OF NEW HAMPSHIRE
Centricut, LLC, Plaintiff
v. Civil No. 99-039-M Opinion No. 2002 DNH 040 Esab Group, Inc., Defendant
v.
Centricut, LLC (New Hampshire) and Centricut, LLC (Delaware), Counterclaim Defendants
O R D E R
Centricut, LLC brought suit against Esab Group, Inc.
("Esab"), holder of United States patent 5,023,425 ("the '425
patent"), seeking a declaratory judgment that: (1) it has not
infringed the '425 patent; (2) the '425 patent is invalid on a
variety of statutory grounds;1 and (3) the '425 patent is
unenforceable under the doctrine of laches and estoppel. Esab
1 Specifically, Centricut asserts that the '425 patent should be declared invalid, void, and/or unenforceable under: (1) 35 U.S.C. § 112, 5 2 (for indefiniteness); (2) 35 U.S.C. § 102(a); (3) 35 U.S.C. § 102(b); (4) 35 U.S.C. § 103 (for obviousness); and (5) 35 U.S.C. § 112, 5 1 (for failure to meet the enablement requirement and to set forth the best m o d e ) . counterclaims against Centricut, LLC (New Hampshire) and
Centricut, LLC (Delaware) (collectively "Centricut"), asserting
infringement of the '425 patent and infringement of United States
patent Des. 384,682. Before the court is Centricut's motion for
summary judgment (document no. 25) on Count I of its petition for
declaratory judgment (which includes its claims of non
infringement and statutory invalidity), and Count I of Esab's
counterclaim (which claims infringement of the '425 patent).
Esab objects. For reasons given below, Centricut's motion for
summary judgment is denied.
Summary Judgment Standard
Summary judgment is appropriate when the record reveals "no
genuine issue as to any material fact and . . . the moving party
is entitled to a judgment as a matter of law." F e d . R. C i v . P.
56(c). "To determine whether these criteria have been met, a
court must pierce the boilerplate of the pleadings and carefully
review the parties' submissions to ascertain whether they reveal
a trialworthy issue as to any material fact." Perez v. Volvo Car
Corp., 247 F.3d 303, 310 (1st Cir. 2001) (citing Grant's Dairy-
2 Me., LLC v. Comm'r of Me. Dep't of Aqric., Food & Rural Res., 2 32
F.3d 8, 14 (1st Cir. 2000)) .
Not every factual dispute is sufficient to thwart summary judgment; the contested fact must be "material" and the dispute over it must be "genuine." In this regard, "material" means that a contested fact has the potential to change the outcome of the suit under the governing law if the dispute over it is resolved favorably to the nonmovant. By like token, "genuine" means that the evidence about the fact is such that a reasonable jury could resolve the point in favor of the nonmoving party.
Navarro v. Pfizer Corp., 261 F.3d 90, 93-94 (1st Cir. 2001)
(quoting McCarthy v. Northwest Airlines, Inc., 56 F.3d 313, 315
(1st Cir. 1995) ) .
In defending against a motion for summary judgment, "[t]he
non-movant may not rely on allegations in its pleadings, but must
set forth specific facts indicating a genuine issue for trial."
Geffon v. Micrion Corp., 249 F.3d 29, 34 (1st Cir. 2001) (citing
Lucia v . Prospect St. High Income Portfolio, Inc., 36 F.3d 170,
174 (1st Cir. 1994)). When ruling upon a party's motion for
summary judgment, the court must "scrutinize the summary judgment
record 'in the light most hospitable to the party opposing
summary judgment, indulging all reasonable inferences in that
3 party's favor.'" Navarro, 261 F.3d at 94 (quoting Griqqs-Rvan v.
Smith. 904 F.2d 112, 115 (1st Cir. 1990)).
Factual Background
Esab makes and sells plasma arc torches that are used for
cutting and welding metal. Centricut makes and sells replacement
electrodes for plasma arc torches manufactured by Esab and
others. In 1998, Esab sued Centricut in the District of South
Carolina for infringing the '425 patent, but the suit was
dismissed for lack of personal jurisdiction. Centricut filed its
petition for declaratory judgment in this court shortly
thereafter. Esab responded with a counterclaim asserting, inter
alia, infringement of the '425 patent.
The '425 patent discloses an electrode for supporting an
electrical arc in a plasma arc torch and teaches a method for
fabricating the electrode. The patented electrode has a metal
emissive insert (which is the intended point of contact for the
electrical arc which allows the torch to cut and weld metal),
surrounded by a metal "sleeve" which is mounted in a "cavity" in
a metal holder, generally made of copper or a copper alloy. At
4 issue here are independent claims 1 , 2 , and 8 of the '425 patent.
Claim 1 recites, in pertinent part:
a metallic holder having a front end, and a cavity in said front end, and an insert assembly mounted in said cavity and comprising an emissive insert composed of a metallic material having a relatively low work function, and a sleeve surrounding said emissive insert so as to separate said emissive insert from contact with said holder, said sleeve having a radial thickness of at least about 0.01 inches at said front end and being composed of a metallic material having a work function which is greater than that of the material of said emissive insert, and said sleeve being composed of a metal which is selected from the group consisting of silver, gold, platinum, rhodium, iridium, palladium, nickel, and alloys wherein at least 50% of the composition of the alloy consists of one or more of said metals . . .
'425 patent, col. 7, 11. 27-43. Claim 2 recites, in pertinent
part:
a metallic holder having a front end, and a cavity in said front end, and an insert assembly mounted in said cavity and comprising an emissive insert composed of a metallic material having a relatively low work function, and a sleeve surrounding said emissive insert so as to separate said emissive insert from contact with said holder, said sleeve having a radial thickness of at least about 0.01 inches at said front end and being composed of a metallic material having a work function which is greater than that of the material of said emissive insert, and said sleeve being composed of an alloy which comprises copper and a
5 second metal which is selected from the group consisting of silver, gold, platinum, rhodium, iridium, palladium, nickel, and alloys thereof, and wherein said second metal comprises at least about 10% of the alloy of copper and the second metal . . .
'425 patent, col. 7, 11. 49-66. Finally, claim 8 recites, in
pertinent part.
a metallic tubular holder defining a longitudinal axis and having a front end and a rear end, and a transverse end wall closing said front end, said transverse end wall having a substantially planar outer front face which is perpendicular to said longitudinal axis, and a cavity formed in said front face and which extends rearwardly along said longitudinal axis, and an insert assembly mounted in said cavity and comprising (a) a generally cylindrical emissive insert disposed coaxially along said longitudinal axis . . . said emissive insert being composed of a metallic material having a relatively low work function so as to be adapted to readily emit electrons upon an electrical potential being applied thereto, and (b) a sleeve positioned in said cavity coaxially about said emissive insert, said sleeve having a radial thickness of at least about 0.01 inches at said front end and being composed of a metallic material having a work function which is greater than that of the material of said holder and greater than that of the material of said emissive insert, said metallic sleeve being selected from the group consisting of silver, gold, platinum, rhodium, iridium, palladium, nickel, and alloys wherein at least 50% of the composition of the alloy consists of one or more of said metals . . .
6 '425 patent, col. 8, 11. 29-58.
The electrode claimed in the '425 patent is purported to be
an improvement over previous electrodes because use of a sleeve
to separate the emissive insert from the holder increases the
use-life of the electrode by preventing the electrical arc from
shifting its point of attachment from the emissive insert to the
holder, which is subject to melting and failure when contacted by
the arc.2
The accused electrode, made and sold by Centricut, includes
an emissive insert, encircled, at the front end of the electrode,
by a "washer" made of a different metal, mounted within a bore
drilled through the holder.
After conducting some discovery, Centricut moved for summary
judgment on Count I of its petition for declaratory judgment and
Count I of Esab's counterclaim. Specifically, Centricut argued
that: (1) the '425 patent is invalid because of indefiniteness
2 Claims 1, 2, and 8 each conclude as follows: "whereby said sleeve acts to resist movement of the arc attachment point from said insert to said holder." '425 patent, col. 7, 11. 44-46, col. 8, 11. 1-3, 59-61.
7 with respect to the work-function limitation on the material from
which the sleeve is made; (2) its electrodes do not literally
infringe the '425 patent because: (a) they have no cavity; (b)
they have no sleeve; and (c) the material from which the washer
is made cannot be shown to have a work function higher than that
of the material of the emissive insert; and (3) its electrodes do
not infringe under the doctrine of equivalents because a washer
brazed into a through-hole is not equivalent to a sleeve
metallurgically bonded to the walls of a cavity. Esab objects,
categorically, to Centricut's motion for summary judgment.
Because the '425 patent had not yet been construed, the
court denied Centricut's motion for summary judgment, without
prejudice, and directed the parties, by order dated April 3,
2001, to file a stipulation as to claim construction, or notify
the court whether the claim construction issues could be resolved
on the briefs or would require a Markman hearing. See Markman v.
Westview Instruments, Inc., 52 F.3d 967 (Fed. Cir. 1995) (in
banc), aff'd 517 U.S. 370 (1996)). Specifically, the court noted
that it could not rule on Centricut's motion for summary judgment
without knowing the precise meaning of the terms "work function," "cavity," and "sleeve." The parties filed a joint response, in
which they: (1) directed the court to their previously filed
papers with respect to the construction of the terms "cavity" and
"sleeve;" and (2) agreed upon a definition of "work function" as
"the potential step, measured in electron volts, which permits
thermionic emission from the surface of a metal at a given
temperature" (Jt. Resp. 1 1 (quoting '425 patent, col. 1, 11. 2 5 -
28)). Neither party requested a Markman hearing, but offered
different preferences as to timing in the event the court deemed
such a hearing necessary for proper construction of the claims.
Discussion
Based upon a review of the parties' moving papers, it does
not appear that a hearing is necessary in order to construe the
'425 patent. Accordingly, the court turns to the issues raised
by Centricut's motion for summary judgment: (1) invalidity due to
indefiniteness; and (2) infringement.
I. Indefiniteness
Centricut argues that independent claims 1, 2, and 8 of the
'425 patent are invalid as indefinite because: (1) the disputed
9 claims discuss the work functions of various metallic materials
rather than the work functions of the surfaces of various metals;
and (2) the patent does not provide sufficient information to
allow one skilled in the art to determine the relative order of
the work functions of the various materials that could be used to
construct the claimed holders, sleeves, and emissive inserts. In
support of its position, Centricut notes, inter alia, that work
function is dependent upon a variety of variables, such as
surface treatment and crystalline structure, which means that an
individual metallic material, such as silver, can have more than
one work function. Esab counters by pointing out the existence
of standard reference texts which contain reliable data on the
work functions of various materials and the availability of
tests, routine in the industry, for determining the work function
of specific samples of a given metallic material. The court
agrees with Esab that the '425 patent is not invalid for
indefiniteness.
According to the patent act, a patent "specification shall
conclude with one or more claims particularly pointing out and
distinctly claiming the subject matter which the applicant
10 regards as his invention." 35 U.S.C. § 112, 5 2. Once a patent
has been issued, its "claims as granted are accompanied by a
presumption of validity based upon compliance with, inter alia, §
112 5 2." S3 Inc. v. nVIDIA Corp.. 259 F.3d 1364, 1367 (Fed.
Cir. 2001) (citing Budde v. Harlev-Davidson, Inc., 250 F.3d 1369,
137 6 (Fed. Cir. 2001)); see also 35 U.S.C. § 282 (Supp. 20 01) ("A
patent shall be presumed valid. . . . The burden of
establishing invalidity of a patent or any claim thereof shall
rest on the party asserting such invalidity."). The presumption
of validity may be overcome only by clear and convincing
evidence. Superior Fireplace Co. v. Majestic Prods. Co., 270
F.3d 1358, 1367 (Fed. Cir. 2001) (citing Kaufman Co. v. Lantech,
Inc., 807 F.2d 970, 973-74 (Fed. Cir. 1986)). However, when a
challenger can demonstrate, by clear and convincing evidence,
that a patent claim fails to meet the definiteness requirement,
the court should declare the claim invalid. See Exxon Research &
Enq'q Co. v. United States, 265 F.3d 1371, 1376 (Fed. Cir. 2001) .
"The test for determining whether a claim meets the
definiteness requirement is 'whether one skilled in the art would
understand the bounds of the claim when read in light of the
11 specification.'" LNP Enq'q Plastics, Inc. v. Miller Waste Mills,
Inc., 275 F.3d 1347, 1359 (Fed. Cir. 2001) (quoting Personalized
Media Communications, LLC v. Int'l Trade Comm'n, 161 F.3d 696,
705) (Fed. Cir. 1998)). "If the claims when read in light of the
specification reasonably apprise those skilled in the art of the
scope of the invention, § 112 demands no more." S3 Inc., 259
F.3d at 1367 (quoting Miles Labs., Inc. v. Shandon, Inc., 997
F.2d 870, 875 (Fed. Cir. 1993)) (additional citations omitted).
As for the necessary level of definiteness, a "claim limitation
[must be] expressed in terms that are reasonably precise in light
of the subject matter." Exxon, 265 F.3d at 1379 (citing
Orthokinetics, Inc. v Safety Travel Chairs, Inc., 806 F.2d 1565,
1576 (Fed. Cir. 1986)). Finally, "[a] determination of claim
indefiniteness is a legal conclusion that is drawn from the
court's performance of its duty as the construer of patent
claims." LPN Enq'q, 275 F.3d at 1353 (quoting Personalized
Media, 161 F.3d at 705) .
Based upon the foregoing legal standard, the claims in the
'425 patent are not void for indefiniteness. In claims 1 and 2,
the inventor discloses an electrode in which the sleeve has a
12 higher work function than the emissive insert, and in claim 8, he
discloses an electrode in which the sleeve has a higher work
function than both the emissive insert and the holder. In all
three claims, the inventor discloses several metals from which
the claimed sleeve may be made. While arguing that those claims
are indefinite, Centricut offers no evidence suggesting that one
skilled in the art would have difficulty in knowing what the
inventor claims as his invention, which is the relevant legal
test. See LPN Enq'q, 275 F.3d at 1349. Rather, Centricut
contends that because several of the metals listed in claims 1,
2, and 8 as suitable for sleeves, such as silver, have more than
one work function - at least one of which is lower than a work
function of one of the metals from which an emissive insert can
be made - it is impossible for one to know whether or not an
electrode with a silver sleeve infringes.
Centricut's argument misses the mark, because the disputed
claims are more than sufficiently definite to indicate their
bounds to one skilled in the art. A sleeve made from a metallic
material with a higher work function than that of the metallic
material of the emissive insert is within claims 1 and 2 while a
13 component made from a metallic material with a work function
equal to or lower than that of the metallic material of the
emissive insert falls outside those claims.3 The claims could
not be more definite on this point. It may well be, as Centricut
claims, that some silver sleeves could be within the claims while
others silver sleeves fall outside the claims, depending upon the
physical characteristics of the particular sample of silver used
and the identity of the metal used for the emissive insert, but
that is not due to any indefiniteness in the claim. Rather, it
is due to the nature of work function as an electro-chemical
characteristic that is dependent upon a variety of variables.
Furthermore, all one must do to make a silver electrode component
that avoids the work-function limitation of claims 1, 2, and 8
is to use silver with the necessary physical characteristics
(surface treatment, crystalline structure, etc.) to give it a
work function equal to or lower than the work function of the
material selected for the emissive insert (and, in the case of
claim 8, the holder). The fact that all forms of all listed
3 As for claim 8, a sleeve made from a metallic material with a work function higher than those of both the emissive insert and the holder is within the claim while a component made from a material with a work function equal to or lower than that of the materials of the emissive insert and the holder falls outside the claim.
14 sleeve materials do not have higher work functions than all forms
of all possible emissive insert materials - the basic factual
assertion on which Centricut relies - is simply inadequate to
establish that one skilled in the art cannot discern the bounds
of the invention claimed in the '425 patent.4 The work-function
limitation of those three claims meets the definiteness
requirement of 35 U.S.C. § 112, 5 2.
Because Centricut has failed to produce clear and convincing
evidence that claims 1, 2, and 8 of the '425 patent are
indefinite, its motion for summary judgment on Count I of its
4 Centricut makes much of its observation that the disputed claims refer to the work functions of various "metallic materials" while work function is defined, in the patent, as the capacity for "thermionic emission from the surface of a metal . . ." (Jt. Resp. 5 1 (emphasis added).) Based upon that observation, Centricut seems to conclude that claims 1, 2, and 8 are indefinite. Centricut's argument, which is unavailing, might have greater force if the disputed claims referred to "metals," rather than "metallic materials," as having work functions, in that several of the relevant metals appear not to have a single work function but, instead, have a range of work functions based upon surface treatment and other variables. However, because the claims refer to "metallic materials," there is no logical or factual ambiguity or inconsistency. In other words, a sample of silver with the (100) surface is one metallic material while a sample of silver with the (110) surface, which presumably has a different work function, is a different metallic material.
15 petition for declaratory judgment, as to invalidity based upon
indefiniteness, is denied.5
11. Infringement
In Count I of its amended complaint, Centricut asserts that
it "has not at any time infringed, and does not now infringe, on
any of the claims in the '425 patent" (Am. Compl. 5 15), and in
its prayers for relief, Centricut asks the court to declare that
it has not infringed that patent (Am. Compl., Prayer B ) . In
Count I of its amended counterclaim, Esab asserts that Centricut
has manufactured and sold electrodes that infringe one or more
claims of the '425 patent (Am. Answer & Countercl. 24-31) .6
5 Centricut also asserts, in footnote 10 of its memorandum of law, that the '425 patent is invalid under 35 U.S.C. § 102(b) as having been anticipated by Japanese Laid-Open Patent Application No. Sho 60-247491. Centricut's bare assertion, accompanied by nothing more than a copy of the Japanese patent, is hardly sufficient to support a grant of summary judgment on Centricut's claim of invalidity. Furthermore, without taking a position on this question, the court notes that the Japanese patent claims an electrode in which the emissive insert is separated from the holder by "a boundary layer . . . formed by plating treatment such as electroplating, chemical plating, etc. or the welding or the deposition of nickel, chrome, etc. . . ." (Pl.'s Mot. Summ. J., Bujold Aff., Ex. K at 2.)
6 The fact that Centricut petitioned for a declaratory judgment of non-infringement before Esab made its infringement claim in this court does not shift the burden of proof on infringement from Esab to Centricut. See Vivid Techs., Inc. v.
16 Centricut contends that it is entitled to judgment as a
matter of law as to infringement on grounds that: (1) its
electrode does not literally infringe the electrode claimed in
the '425 patent because: (a) it has a bore or through-hole rather
than a cavity; (b) it has a washer rather that a sleeve; and (c)
the material of its washer cannot be shown to have a work
function higher than the work function of material of its
emissive insert; and (2) the Centricut electrode does not
infringe under the doctrine of equivalents because a washer and
emissive insert brazed into a through-hole are not equivalent to
a sleeve that completely surrounds an emissive insert and that is
metallurgically bonded to the walls of a cavity.
Under the United States Patent Act, "[e]xcept as otherwise
provided . . . whoever without authority makes, uses, offers to
sell, or sells any patented invention, within the United States
or imports into the United States any patented invention during
Am. Science & Enq'q, Inc., 200 F.3d 795, 802 (Fed. Cir. 1999) (citing 12 J a m e s W m . M o o r e e t a l . , M o o r e ' s F e d e r a l P r a c t l c e § 57.62[2] [d] (3rded. 1997)). In other words, by filing its declaratory judgment action, Centricut did not obligate itself to prove a negative, i.e., that its electrode does not infringe the '425 patent, either literally or under the doctrine of equivalents.
17 the term of the patent therefor, infringes the patent." 35
U.S.C. § 271(a) (Supp. 2001).
An infringement analysis requires two steps: construction of the claims, to determine their scope and meaning, and comparison of the properly construed claims to the allegedly infringing device or method. Cybor Corp. v. FAS Techs., Inc., 138 F.3d 1448, 1454 (Fed. Cir. 1998) (en banc) . Claim construction . . . is a matter of law . . . . Lockheed Martin Corp. v. Space Svs./Loral, Inc., 249 F.3d 1314, 1323 (Fed. Cir. 2001). The comparison of claims to the accused device or method, and the corresponding determination of infringement, whether literal or under the doctrine of equivalents, is a question of fact. Tanabe Seivaku Co. v. United State Int'l Trade Comm'n, 109 F.3d 726, 731 (Fed. C i r . 19 97).
J & M Corp. v . Harlev-Davidson, Inc., 269 F.3d 1360, 1366 (Fed.
Cir. 2001) (parallel citations omitted).
A. Claim Construction
This case presents two issues of claim construction: (1)
whether the claimed "cavity" in the electrode's holder is limited
to a hole that extends only partway through the holder, or may
consist of a hole that goes all the way through; and (2) whether
the claimed "sleeve" must separate the emissive insert from the
holder at all possible points of contact, or may separate the
emissive insert and the holder at some but not all possible
18 points of contact. According to Centricut, the term "cavity"
does not include a bore or through-hole, and the term "sleeve"
does not include anything that does not provide total separation
between the emissive insert and the holder.
"It is well-settled that, in interpreting an asserted claim,
the court should look first to the intrinsic evidence of record,
i.e., the patent itself, including the claims, the specification
and, if in evidence, the prosecution history." Vitronics Corp.
v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996)
(citing Markman v. Westview Instruments, Inc., 52 F.3d 967, 979
(Fed. Cir. 1995) (in banc), aff'd 517 U.S. 370 (1996)). When
examining the intrinsic evidence, the court should first "look to
the words of the claims themselves, both asserted and
nonasserted, to define the scope of the patented invention."
Vitronics, 90 F.3d at 1582 (citing Bell Communications Research,
Inc. v. Vitalink Communications Corp., 55 F.3d 615, 620 (Fed.
Cir. 1995)). When doing so, the court must bear in mind the
"heavy presumption in favor of the ordinary meaning of claim
language." Kraft Foods, Inc. v. Int'l Trading Co., 203 F.3d
1362, 1366 (Fed. Cir. 2000) (quoting Johnson Worldwide Assocs.,
19 Inc. v. Zebco Corp., 175 F.3d 985, 989 (Fed. Cir. 1999)). After
considering the ordinary meaning of the claim language, the court
should "review the specification to determine whether the
inventor has used any terms in a manner inconsistent with their
ordinary meaning," Vitronics, 90 F.3d at 1582, but "any special
definition given to a word must be clearly defined in the
specification," Kraft Foods, 203 F.3d at 1266 (quoting Markman,
52 F.3d at 980). Finally, "the court may also consider the
prosecution history of the patent, if in evidence." Vitronics,
90 F.3d at 1582 (citing Markman, 52 F.3d at 980; Graham v. John
Deere C o ., 383 U.S. 1 (1966)). However, while "the written
description may aid in the proper construction of a claim term,
limitations, examples, or embodiments appearing only there may
not be read into the claim." Kraft Foods, 203 F.3d at 1366
(citing Comark Communications, Inc. v. Harris Corp., 156 F.3d
1182, 1186-87 (Fed. Cir. 1998)).
1. Cavity
With respect to the proper construction of the cavity
element of the patent claims, both parties rest on the arguments
in their summary judgment papers. According to Centricut, the
20 '425 patent claims a cavity, which necessarily has an open outer
end and a closed inner end.7 Centricut further argues that the
distinction it draws between a cavity (with an open outer (or
front) end and a closed inner (or back) end) and a through-hole
or bore (with an open outer end and an open inner end) is
supported by the ' 425 patent itself, which uses the term "cavity"
to describe the recess filled by a sleeved emissive insert and
the term "bore" to describe certain open passageways, elsewhere
in the electrode, designed to permit the flow of gas or water.
See, e.g., '425 patent, col. 4, 11. 64-66, col. 5, 11. 50-52.
According to Esab, Centricut's proposed construction is
unavailing because: (1) the distinction between a blind cavity
(i.e., one with a single opening) and a cavity with more than one
opening is immaterial when, as here, the cavities in question are
both completely filled (with an emissive insert); (2) Centricut
limits the term cavity to include only blind cavities by
impermissibly treating as a claim limitation a physical
characteristic drawn from one of the preferred illustrative
embodiments in the specification; and (3) Centricut's distinction
7 Centricut contrasts the cavity claimed in the '425 patent with the analogous feature in the accused electrodes, which it characterizes as a through-hole or bore, which has an open outer end and an open inner end.
21 between a cavity and a bore ignores the dictionary definition of
"bore" as "an interior lengthwise cylindrical cavity."
The term "cavity," as used in the '425 patent, encompasses
both blind cavities and those with openings at both ends. The
relevant claims in the patent all disclose a metallic holder with
a front end and a cavity in the front end. See '425 patent, col.
7, 11. 27-28, 11. 48-48, col. 8, 11. 29-36. In other words, a
cavity is an open space formed (and subsequently filled) in the
front end of the metallic holder.8 Whether such an opening
continues through to the back end or terminates somewhere short
of the back end is not asserted in the claim. See Vitronics, 90
F.3d at 1582 (explaining that proper claim construction takes
into account the words of the claim "both asserted and
nonasserted) (citation omitted). The plain language of the
patent does not limit the claim to blind cavities. Because the
relevant claims recite the element of a cavity in the front end,
and because a holder with a through-hole meets the limitation of
having a cavity in its front end, the cavity element may not be
8 A definition of the term "cavity" that refers exclusively to the front end of the electrode is entirely consistent with the electrode's function, given that the front end is the part of the electrode to which the electrical arc attaches.
22 construed with the additional limitation urged by Centricut,
which it reads into the claim from other parts of the patent.
See Kraft Foods, 203 F.3d at 1366 (limitation appearing only
elsewhere in the patent may not be read into the claim). In
short, for purposes of construing the '425 patent, the term
"cavity" includes both blind cavities and through-holes.9
2. Sleeve
As with the cavity element, both parties rest on the
arguments in their summary judgment papers. According to
Centricut, the '425 patent claims a sleeve, which necessarily
separates the emissive insert from the holder at all possible
points of contact.10 Esab counters that: (1) the claimed sleeve
9 While there is some logic to Centricut's argument that the patent specification uses the term cavity to describe the space filled by the emissive insert and the term bore to describe a cylindrical passageway open on both ends, the force of that argument is substantially diminished by the fact that the cavities in the specification are all filled while the bores identified in the specification remain open for the transmission of gas or water. In other words, to the extent the '425 patent includes a meaningful distinction between cavities and bores, the distinction is based not on the number of openings (one versus two), but, instead, on whether the space has been filled (as with the cavities) or remains open (as with the bores).
10 Centricut contrasts the sleeve claimed in the '425 patent, which it likens to a top hat, with the analogous feature in the accused electrodes, which it characterizes as a washer and
23 need not enclose the emissive insert on all sides to separate it
from the holder; and (2) Centricut impermissibly incorporates a
"complete encirclement" limitation into the claims from language
elsewhere in the specification describing one of the preferred
embodiments.
The term "sleeve," as used in the '425 patent, encompasses
both sleeves that separate the emissive insert from the holder by
completely encircling it and those that separate the emissive
insert from the holder by partially encircling it, so long as the
emissive insert is entirely encircled by the sleeve at its front
end and has a radial thickness of at least about 0.01 inches.11
The electrodes disclosed in claims 1 and 2 have
a sleeve surrounding said emissive insert so as to separate said emissive insert from contact with said holder, said sleeve having a radial thickness of at
likens to the brim of a top hat. (In the '425 patent, the "brim" of the top hat is called the "annular flange," '425 patent, col. 3, 1. 52, and the "stovepipe" portion of the hat is called the "peripheral wall," '425 patent, col. 3, 1. 49.)
11 "Encircled" may not be the most apt term to describe a three-dimensional object that is surrounded on all sides, to the extent a circle (as opposed to a sphere) is a two-dimensional geometric figure. Nevertheless, when the court refers to the emissive insert as being "encircled," the intent is to refer to all three dimensions.
24 least about 0.01 inches at said front end . . . whereby said sleeve acts to resist movement of the arc attachment point from said insert to said holder.
'425 patent, col. 7, 11. 32-33, 44-46. The electrode disclosed
in claim 8 has
a sleeve positioned in said cavity coaxially about said emissive insert, said sleeve having a radial thickness of at least about 0.01 inches at said front end . . . whereby said sleeve acts to resist movement of the arc attachment point from said insert to said holder.
'425 patent, col. 8, 11. 47-50, 11. 59-61.
Nowhere do claims 1, 2, or 8 limit the patented invention to
a sleeve that fully surrounds the emissive insert. Rather, the
sleeve surrounds the emissive insert (or is positioned about it)
by virtue of separating the emissive insert from the holder, for
the purpose of resisting movement of the arc from the emissive
insert to the holder. Because the arc attachment point is
necessarily on the front end of the emissive insert (or, in the
case of electrode failure, on the front end of the holder), and
because the only dimensions in claims 1, 2, or 8 that pertain to
the sleeve specify its radial thickness at the front end, it
necessarily follows that the emissive insert is surrounded.
25 within the meaning of the '425 patent, when the sleeve (or other
analogous element) has a radial thickness of at least about 0.01
inches and as much depth as is necessary to allow the sleeve to
resist the movement of the arc attachment point from the emissive
insert to the holder. In other words, the term "sleeve," as used
in the '425 patent, includes both long sleeves that run the full
length of the emissive insert and short sleeves that run only
part of the length of the emissive insert.
B. Literal Infringement
Centricut argues that the accused electrodes do not
literally infringe the '425 patent because: (1) they do not have
a cavity; (2) they do not have a sleeve; and (3) even if the
washer in the Centricut electrode is a sleeve, or equivalent to
the sleeve claimed in the '425 patent, there is no evidence
showing that the washer in the Centricut electrode is made from a
metallic material with a higher work function than the metallic
material of the emissive insert. Esab counters that the
Centricut electrode has both a cavity and a sleeve, within the
meaning of the '425 patent as properly construed.
26 "A claim is literally infringed when the accused device
literally embodies each limitation of the claim." Kraft Foods,
203 F.3d at 1370 (citing Pall Corp. v. Micron Separations, Inc.,
66 F .3d 1211, 1217 (Fed. Cir. 1995))
For reasons given above, the court construes the term
"cavity" to include both blind cavities, as depicted in Figure 1
of the '425 patent, and through-holes such as those in the
Centricut electrode. Similarly, the court construes the term
"sleeve" to include both long sleeves, as depicted in Figure 1 of
the '425 patent, and short sleeves, such as the washer in the
Centricut electrode. Because the Centricut electrode has a
cavity, within the meaning of the '425 patent, and because the
undisputed factual record does not demonstrate that the Centricut
washer has a radial thickness of less than about 0.01 inches,
Centricut has failed to demonstrate that Esab cannot prove that
the Centricut electrode embodies the "cavity" and "sleeve"
elements of claims 1, 2, and 8 of the '425 patent. Furthermore,
while Centricut has produced facts supporting the possibility
that the material from which its washers are made could have a
work function lower than the work function of the material from
27 which its emissive inserts are made, that is not enough to
prevent Esab from proving that Centricut's washers have a higher
work function than its emissive inserts,12 and Esab has produced
evidence suggesting that there would be no reason for Centricut
to use a washer in its electrode unless it was made from a
material with a higher work function than the emissive insert.
Accordingly, Esab has demonstrated the existence of a triable
issue of material fact relative to the work function of the
material from which Centricut makes the washers for its
electrodes, thus precluding summary judgment for Centricut on the
issue of literal infringement.
Because Esab has made a showing sufficient to resist summary
judgment on the issue of literal infringement, Centricut's motion
for summary judgment, as to that issue (which is raised in both
Count I of its amended complaint and Count I of Esab's amended
12 Centricut devotes considerable energy to showing that not all silver has the same work function, due to variables such as crystalline structure, surface treatment, and the like. However, the mere fact that a person cannot know the work function of a piece of metal simply by knowing that the metal is silver does not mean that the work function of any particular piece of silver cannot be ascertained either through testing or knowledge of its crystalline structure, surface treatment, and other physical characteristics .
28 counterclaim), is denied. Esab has not moved for summary
judgment on its infringement claim, but at this juncture the
court makes the following observations: (1) given the court's
construction of the term "cavity," there would appear to be no
triable issue of material fact to preclude a finding that the
accused electrode embodies the cavity element of the disputed
claims; (2) the only issue of material fact pertaining to
embodiment of the sleeve element is whether Centricut's short
sleeve is long enough to resist movement of the arc attachment
point from the emissive insert to the holder; and (3) the only
issue of material fact related to the work-function limitation is
whether Centricut's sleeves are made from a metallic material
with a work function higher than that of the metallic material
from which its emissive inserts are made.
C. Infringement under the Doctrine of Eguivalents
In addition to claiming that the accused electrode does not
literally infringe the '425 patent, Centricut argues that the
electrode is not an infringing equivalent. Esab disagrees, and
suggests - without so moving - that it is entitled to summary
judgment on the issue of infringement by equivalents. Because
29 Centricut is not entitled to summary judgment as to literal
infringement, thus leaving open the possibility that Esab could
prevail on that claim, there is no occasion to decide the issue
of infringement by equivalents. See Graver Tank & Mfg. Co. v.
Linde Air Prods. Co., 339 U.S. 605, 607 (1950) ("If accused
matter falls clearly within the claim, infringement is made out
and that is the end of it."). Accordingly, Centricut's motion
for summary judgment on the issue of infringement by equivalents
(as raised in both Count I of Centricut's amended complaint and
Count I of Esab's amended counterclaim) is denied because the
question of infringement by equivalents is not ripe for decision
unless and until the court decides that Centricut's electrodes do
not literally infringe the '425 patent.
Conclusion
For the reasons given, Centricut's motion for summary
judgment (document no. 25) is denied. The '425 patent retains
the presumption of validity, and the case shall remain on the
trial calendar.
30 SO ORDERED.
Steven J. McAuliffe United States District Judge
February 7, 2002
cc: Edward A. Haffer, Esq. Micheal J. Bujold, Esq. Neal E. Friedman, Esq. John R. Hughes, Jr., Esq. Bias P. Arroyo, Esq.