United States Court of Appeals
      for the Federal Circuit
                 ______________________

PLASTIC OMNIUM ADVANCED INNOVATION AND
               RESEARCH,
             Plaintiff-Appellant

                            v.

DONGHEE AMERICA, INC., DONGHEE ALABAMA,
                   LLC,
           Defendants-Appellees
          ______________________

                       2018-2087
                 ______________________

    Appeal from the United States District Court for the
District of Delaware in No. 1:16-cv-00187-LPS, Chief Judge
Leonard P. Stark.
                 ______________________

       SEALED OPINION ISSUED: November 21, 2019
       PUBLIC OPINION ISSUED: December 3, 2019 *
                ______________________

    ALEXANDER HADJIS, Oblon, McClelland, Maier and
Neustadt, LLP, Alexandria, VA, argued for plaintiff-appel-
lant. Also represented by ROBERT CARTER MATTSON,
CHRISTOPHER RICCIUTI.



   *   This opinion was originally filed under seal and has
been unsealed in full.
2        PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.




    ERIC SHUMSKY, Orrick, Herrington & Sutcliffe LLP,
Washington, DC, argued for defendants-appellees. Also
represented by MELANIE L. BOSTWICK, JEREMY PETERMAN;
ALYSSA MARGARET CARIDIS, Los Angeles, CA; EDMUND
HIRSCHFELD, New York, NY.
                ______________________

Before NEWMAN, CLEVENGER, and REYNA, Circuit Judges.

     Opinion for the court filed by Circuit Judge REYNA.

    Dissenting opinion filed by Circuit Judge CLEVENGER.

REYNA, Circuit Judge.
    Plastic Omnium Advanced Innovation and Research
appeals from a grant of summary judgment of noninfringe-
ment by the U.S. District Court for the District of Dela-
ware. The district court’s determinations on summary
judgment are consistent with its claim construction and
supported by undisputed facts in the record. We affirm.
                        BACKGROUND
                  A. The Asserted Patents
    Plastic Omnium Advanced Innovation and Research
(“Plastic Omnium”) owns U.S. Patent Nos. 6,814,921 (“the
’921 patent”) and 6,866,812 (“the ’812 patent”). The pa-
tents generally relate to manufacturing plastic fuel tanks
formed by blow molding. The fuel tanks are formed in a
way that allows accessory components to be installed in-
side the fuel tank without cutting holes in the tank wall,
which could compromise the structural integrity of the
wall. A conventional blow molding system is depicted be-
low:
PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.          3




J.A. 3482 (Appellee’s Technology Tutorial). The image
shows the general placement and geometry of the extruder
head, die, parison, and molding cavity in a conventional
blow molding process.
    The sole figure (shown below) of the ’812 patent is rep-
resentative of the disclosed system and depicts a tubular
“parison” that is formed using an extrusion head (compo-
nent 2) and circular die mounted on the extrusion head. As
the parison exits the extrusion head, a blade (component 3)
located at the exit of the die splits the parison.
4        PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.




’812 patent Fig. 1, col. 5 ll. 28–30; see also ’921 patent
col. 5 l. 25.
    Claim 1 of the ’921 patent recites the following, includ-
ing the disputed “extruded parison” limitation:
    1. A process for manufacturing plastic hollow bod-
    ies from two shells formed by molding, which are
    joined together, at least one shell being produced
    by compression-molding a portion of a plastic sheet
    between a mold and a punch and by the remaining
    portion of the sheet being blow-molded in the re-
    gion not compression-molded, characterized in that
    it is applied to the manufacture of a fuel tank and
    in the sheet is obtained in the same manufacturing
    line as the shell which will be produced from this
    sheet, by the cutting and opening an extruded par-
    ison of closed cross section.
PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.              5



’921 patent col. 5 l. 44–col. 6 l. 6 (emphasis added to dis-
puted term). Claim 32 of the ’812 patent includes a similar
disputed term: “extruding a parison.”
               B. District Court Proceedings
    On March 23, 2016, Plastic Omnium filed suit against
Donghee America, Inc., and Donghee Alabama, LLC (col-
lectively “Donghee”) in the District of Delaware, asserting
infringement of several patents. The ’921 and ’812 patents
were among the eight patents in Plastic Omnium’s
amended complaint. After claim construction, Donghee
moved for summary judgment of noninfringement as to the
asserted claims of the ’921 and ’812 patents and on other
bases not at issue in this appeal. On May 22, 2018, the
district court granted Donghee’s summary judgment mo-
tion. The district court entered final judgment on June 11,
2018.
                   1. Claim Construction
     During claim construction, the parties disputed the
meaning of the term “parison.” Plastic Omnium Advanced
Innovation & Research v. Donghee Am., Inc., No. 16-CV-
187, 

, at *3–4 (D. Del. Nov. 6, 2017)
(“Claim Construction Order”). Donghee argued that it
should be given its plain and ordinary meaning of “hollow
plastic tube exiting the die of an extrusion head.” 

Plastic Omnium argued that the patentee had acted as its
own lexicographer and that “the ’921 and ’812 patents do
not use the term ‘parison’ [in] its conventional, plain and
ordinary meaning.” 

court agreed with
Plastic Omnium and reasoned that “the patents specify
that the ‘parison’ is cut in two as it leaves the die at the end
of the extrusion head” and so “this ‘parison’ cannot be
strictly limited to a fully-formed tubular structure existing
in its entirety outside the extrusion head/die.” 

It
recognized that “the principal disagreements between the
parties [were] identifying the point at which the molten
plastic within the extrusion head becomes a ‘parison,’ and
6        PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.




identifying the location of the die.” 

court
rejected Plastic Omnium’s contention that the “claimed
process includes the splitting of molten plastic within the
extrusion head/die” based on its determination that neither
specification discloses “splitting of the tubular preform at
any stage earlier than right as the previously tubular
structure leaves the die/extrusion head.” 

tations omitted). The district court also clarified that “the
‘extruded parison’ terms should not include molten plastic
(or a tubular preform) present inside the die/extrusion
head and that the “‘die’ is located at the ‘extrusion head[’s]’
‘lowest point,’” rejecting Plastic Omnium’s contention that
the “die” could be located anywhere. 

*4 n.4 (quot-
ing ’921 patent col. 3 ll. 4–5; ’812 patent col. 2 ll. 37–38).
Accordingly, the district court construed “parison” as “re-
ferring to a plastic tube with a closed cross section that is
shaped by—and has reached the end of—a die and is split
either immediately upon exiting the die or at some point
thereafter.” 

Building upon that construction, the
district court construed “extruded parison of closed cross
section” and “extruding a [multilayered] parison” as “a tub-
ular preform with a closed cross-section that has been
forced through a die and is cut or split as it exits the die or
at some time thereafter” and “a [multilayered] tubular pre-
form with a closed cross-section that has been forced
through a die and is cut or split as it exits the die or at some
time thereafter,” respectively. 

(alterations in orig-
inal).
                   2. Summary Judgment
    Donghee moved for summary judgment of noninfringe-
ment of five asserted patents, including the ’921 and ’812
patents involved in this appeal. 1 Donghee argued that its


    1  This appeal also included U.S. Patent Nos.
7,166,253 and 9,399,327. Plastic Omnium filed a Motion to
Withdraw those patents from this appeal which we grant
PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.                7



accused product does not infringe the asserted claims of the
’921 and ’812 patents because it “does not extrude a pari-
son.” Plastic Omnium Advanced Innovation & Research v.
Donghee Am., Inc., 

, 416–17 (D. Del.
2018) (“Summary Judgment Order”). Relying on its claim
construction of the “parison” terms, the district court
granted summary judgment of noninfringement. 

literal infringement, the district court recognized
that there was no dispute that Donghee’s “‘manufacturing
process begins by forcing plastic through a circular coex-
trusion head, and then feeding the plastic that exits the
coextrusion head into a separate piece of equipment, re-
ferred to as a flat die tool,’ and that once inside ‘the flat die,
the molten plastic is cut into two streams of plastic which
are extruded as two sheets.’” 

(citing Donghee’s
brief in support of its motion for summary judgment and
Plastic Omnium’s brief in opposition). Turning to its claim
construction holdings, the district court reiterated its de-
terminations that (1) “parison” was not limited to a fully
formed tubular structure that exists entirely outside of the
extrusion head/die, i.e., the “parison” may be cut as it exits
the die at the end of the extrusion head; (2) the tubular
preform cannot be split at any stage prior to its exit of the
extrusion head/die such that molten plastic or a tubular
preform present inside the extrusion head/die is excluded
from the claim scope; and (3) the die must be located at the
extrusion head’s lowest point. 

Construc-
tion Order, 

, at *4).
    According to the district court, “[b]ecause the splitting
does not occur ‘at any stage earlier than right as the previ-
ously tubular structure leaves the die/extrusion head,’ the
claim construction makes clear that whether the extrusion
equipment consists of a single combined extrusion head


(see Conclusion) and therefore do not address those patents
in the Background.
8       PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.




with a die or a more complex extrusion head with a sepa-
rate attached die, the splitting of the molten plastic must
not occur inside any of the extrusion head/die equipment.”

omitted and emphases added). Quot-
ing Plastic Omnium’s brief in opposition of summary judg-
ment, the district court found that there was no genuine
dispute of material fact that Donghee’s accused product
does not literally infringe because “for the accused product,
it is undisputed that ‘[t]he extruded plastic parison is [ ]
cut in a separate “flat die” tool after it leaves Donghee’s
coextrusion die.’” 

alterations in origi-
nal).
     The district court also concluded that Donghee’s ac-
cused product did not infringe under the doctrine of equiv-
alents. According to the district court, “a reasonable jury
could not find [that the] cutting [of] the parison while it is
extruding within extrusion equipment is insubstantially
different than [the] cutting [of] the extruded parison out-
side the extrusion equipment.” 

The district
court also pointed to statements by Dr. Osswald, Plastic
Omnium’s expert, where he acknowledged differences be-
tween Donghee’s “flat die tool” and the claimed invention.

387; 431).
   Plastic Omnium appeals. We have jurisdiction under
28 U.S.C. § 1295(a)(1).
                        DISCUSSION
    We review a grant of summary judgment under the law
of the applicable regional circuit, here the Third Circuit.
ArcelorMittal Atlantique et Lorraine v. AK Steel Corp., 

, 1273 (Fed. Cir. 2018). The Third Circuit reviews
a grant of summary judgment de novo. Gonzalez v. Sec’y of
Dep’t of Homeland Sec., 

, 257 (3d Cir. 2012).
   Plastic Omnium challenges the district court’s grant of
summary judgment of no literal infringement and no
PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.             9



infringement under the doctrine of equivalents as to the
’921 and ’812 patents. We address each argument in turn.
                  A. Literal Infringement
     Plastic Omnium argues that the court granted sum-
mary judgment based on an erroneous claim construction.
Appellant Br. 32. According to Plastic Omnium, the dis-
trict court’s summary judgment improperly imposed a “cut-
ting location requirement.” 

We disagree.
     We first note that despite its argument that summary
judgment was based on an erroneous claim construction,
Plastic Omnium does not dispute the district court’s con-
struction of “extruded parison of closed cross section” as “a
tubular preform with a closed cross-section that has been
forced through a die and is cut or split as it exits the die or
at some time thereafter.” Nor does it dispute the construc-
tion of “extruding a [multilayered] parison” as “a [multi-
layered] tubular preform with a closed cross-section that
has been forced through a die and is cut or split as it exits
the die or at some time thereafter.” Rather, Plastic Om-
nium argues that the district court erred by deviating from
its claim construction order and requiring “the claimed par-
ison to be cut or split outside of the extrusion equipment.”

determine whether the correct applica-
tion of the district court’s claim construction excludes the
accused Donghee product based on the undisputed facts.
We conclude that it does.
     Claim 1 of the ’921 patent requires “cutting and open-
ing of an extruded parison of closed cross section.” ’921 pa-
tent col. 5 l. 44–col. 6 l. 5 (emphasis added). Claim 32 of
the ’812 patent requires “extruding a parison” and then
“cutting through said parison so as to form two portions
separated by a cut . . . .” ’812 patent col. 7 ll. 14–18 (em-
phasis added). In construing the “parison” terms, the dis-
trict court made clear that “extruded parison [] should not
include molten plastic (or a tubular preform) [] inside the
die [or] extrusion head” and that the “‘die’ is located at the
10       PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.




‘extrusion head[’s]’ ‘lowest point.’” Claim Construction Or-
der, 

at *4, *4 n.4. Thus, no “extruded
parison” is formed until a plastic tube, which implies some
depth, of a closed cross section passes through and exits the
die located at the lowest point of the extrusion head. The
district court rejected Plastic Omnium’s contention that
the claims included splitting plastic inside the extrusion
head or die and its contention that the die could be located
anywhere in the extrusion equipment. See 

     The district court’s determination on summary judg-
ment is consistent with its Claim Construction Order. The
district court first recognized two undisputed facts about
Donghee’s process: (1) the process begins with forcing plas-
tic into a “coextrusion head” and then feeding the plastic
into a separate “flat extrusion die;” and (2) “once inside the
flat die, the molten plastic is cut into two streams of plastic
which are extruded as two sheets.” Summary Judgment

–17 (internal quotations omit-
ted). In view of its Claim Construction Order, the district
court determined that regardless of Plastic Omnium’s ar-
gument that the “coextrusion head” was itself a “die,” the
claim construction “makes clear” that “the splitting of the
molten plastic must not occur inside any of the extrusion
head/die equipment.” 

In other
words, the claims require that the extruded parison is split
after passing through the extrusion head and die.
     It is undisputed that Donghee’s accused product is
manufactured by a process where two separate plastic
sheets are extruded from the die located at the lowest point
of the extrusion head using what is referred to as a “flat die
system.” Appellant Br. 40 (citing J.A. 710–11, 736–38,
784); see also 

The flat die does not produce an
extruded parison as required by the claims, but two
separate plastic sheets, which are not cut at the point of
exiting the die or thereafter. Instead, in the accused
system, molten plastic is injected directly from the
extrusion head into the die mounted directly on the
PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.           11



extrusion head where it is split into two sheets and formed
in the die as shown in the images below.




J.A. 451.
     As seen in the images, Donghee’s own product
literature refers to the plastic entering the flat die tool as
a “parison.” But the district court correctly determined in
its claim construction—accepting Plastic Omnium’s
arguments—that the patentee gave the term “parison” a
special definition, and the patents “do not use the term
‘parison’ [in] its conventional, plain and ordinary
meaning.” Claim Construction Order, 

,
at *4. Thus, the patentee’s definition of “parison” in the
specification and as construed by the court—not Donghee’s
12       PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.




product literature—controls whether the accused product
falls withing the scope of the claim. See Martek Biosciences
Corp. v. Nutrinova, Inc., 

, 1380 (Fed. Cir.
2009); see also Phillips v. AWH Corp., 

, 1316
(Fed. Cir. 2005) (en banc) (“[O]ur cases recognize 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. In such cases, the inventor’s
lexicography governs.”). Thus, despite the fact that
Donghee’s product literature uses the term “parison” to
refer to plastic at the inlet of the flat die, it does not depict
that an “extruded parison” as defined by the patentee
acting as its own lexicographer and construed by the
district court has formed at that point. Donghee’s product
literature does not show a tubular structure as required by
the Claim Construction Order. And as noted above, it is
undisputed that the plastic passing into the flat die is
molten, which the Claim Construction Order specifically
excludes.
     Plastic Omnium argues that the district court’s
quotation of its brief in opposition to summary judgment
shows that the district court concluded that there was no
dispute that an “extruded plastic parison” exits Donghee’s
“coextrusion die.”      See, e.g., Appellant Br. 38; Oral
Argument          at       3:55–4:31,       available        at
http://www.cafc.uscourts.gov/oral-argument-recordings
(citing J.A. 20). This argument is contrary to the record
because, at oral argument, Donghee disputed Plastic
Omnium’s contention. See Oral Argument at 45:56–47:09.
The district court recognized that the heart of the dispute
was whether a parison is extruded at all: “Donghee argues
that the accused product does not infringe the Parison
Claims because it does not extrude a parison.” Summary
Judgment 

(footnote removed)
(emphasis added). The district court further characterized
“the parties’ dispute [as] center[ing] on whether (1) the first
piece of equipment, the ‘coextrusion head,’ is or has a die,
PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.            13



and (2) the extruded parison may continue to be located in
the second piece of equipement, the ‘flat die,’ and still be
held to infringe.” 

s removed).
Further, the district court’s Claim Construction Order also
recognized that “the principal disagreements between the
parties seem to be identifying the point at which the molten
plastic within the extrusion head becomes a ‘parison,’ and
identifying the location of the die.” Claim Construction
Order, 

, at *4.
    We are thus not persuaded by Plastic Omnium’s
contention that the district court’s citation and quoation of
Plastic Omnium’s opposition brief shows that the district
court determined that it was undisputed that an “extruded
parison” leaves the “coextrusion die.” The district court
understood that the claims require a parison to be extruded
from a die located at the lowest point of the extrusion
equipment and that the splitting of the plastic must not
occur inside the die. See Summary Judgment 

(“[T]he claim construction makes clear
that whether the extrusion equipment consists of a single
combined extrusion head with a die or a more complex
extrusion head with a separate attached die, the splitting
of the molten plastic must not occur inside any of the
extrusion head/die equipment.” (emphasis added)).

     Plastic Omnium’s arguments rely heavily on recasting
the “coextrusion head” in the accused system as a “coextru-
sion die,” and Plastic Omnium contends that the plastic
melt flowing from the extrusion head and directly into the
flat die satisfies the extruded parison limitation. Appellant
Br. 40. But “extrusion head” and “die” as used in the as-
serted patents are distinct terms. E.g., ’812 patent col. 2
ll. 35–38 (stating “an extruder whose head is terminated by
the die”); id at col. 2 ll. 46–48 (“In accordance with the pro-
cess according to the invention, at least one cut is made in
the parison leaving the die mounted on the extrusion
head.”); 

ll. 23–30 (“The tubular multilayer extru-
date (1) . . . leaves the extrusion head (2) and is separated
14      PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.




into two sheets (1), using two steel blades (3) placed at 180˚
to each other, at the exit of the circular die mounted on the
extrusion head (2).”); ’921 patent col. 3 ll. 2–5 (“One exam-
ple is that of a sheet produced by extrusion, in an extruder
placed vertically, the extrusion head which includes the die
being located at the lowest point.”). The court’s claim con-
struction order similarly uses “extrusion head” and “die” as
distinct terms. Claim Construction Order, 

, at *3–4 (“[T]he patents specify that the ‘parison’
is cut in two as it leaves the die at the end of the extrusion
head.”). Thus, the claims require that the extrusion head
and die are distinct components that the “parison” must
pass through before it is split.
    Dr. Osswald admitted that the patents disclose that
there is “a die mounted on the extrusion head” but still took
the position that there is actually no die mounted on “an
extrusion head or a co-extrusion die or a co-extrusion head,
whatever you want to call it.” J.A. 1926 (Osswald Dep. Tr.
151:11–152:15.). He justified the apparent contradiction of
his position by asserting that the language of the patents
“may just be a poor choice of words.” 

cited no
contrary evidence and merely speculated that the die is not
a separate part mounted on the extrusion head in the pa-
tents.
     Dr. Osswald also asserted that “if there’s nothing that
comes after [the extrusion head in Donghee’s accused prod-
uct], you extrude a tube or tubular parison.” J.A. 1926
(Osswald Dep. Tr. 151:18–20) (emphasis added). Plastic
Omnium argues that this testimony demonstrates that the
accused product satisfies the extruded parison limitation.
It is undisputed, however, that in Donghee’s accused prod-
uct, the “flat die” comes after the extrusion head. See J.A.
262 (“Donghee’s process utilizes a separate ‘flat die tool’
that forms two sheets of plastic . . . .”). The flat die is
mounted directly on the extrusion head, and thus no tube
or tubular parison is extruded from the extrusion head.
That molten plastic may pass through a “spiral mandrel”
PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.           15



in the bottom of the extrusion head as it passes directly into
and is split within the flat die is not sufficient. Donghee’s
system thus does not satisfy the “extruded parison” limita-
tion under the district court’s claim construction.
    In summary, Donghee’s accused product is different
from the claimed system. The asserted claims require that
a tubular parison is first extruded and cut at the point of
extrusion or sometime thereafter. In the accused system,
the plastic is split and formed within the die, and what is
extruded is two formed plastic sheets, not a parison. Ac-
cordingly, we affirm the district court’s grant of summary
judgment of no literal infringement.
   B. Infringement Under the Doctrine of Equivalents
    Plastic Omnium argues that the district court erred in
granting summary judgment of noninfringement under the
doctrine of equivalents by improperly reading in a cutting
location requirement and ignoring that the steps in the
claimed process and in the accused product are the same
no matter where the splitting of the parison occurs. Appel-
lant Br. 41–42.
    “A finding of infringement under the doctrine of equiv-
alents requires a showing that the difference between the
claimed invention and the accused product or method was
insubstantial or that the accused product or method per-
forms the substantially same function in substantially the
same way with substantially the same result as each claim
limitation of the patented product or method.” AquaTex
Indus., Inc. v. Techniche Sols., 

, 1326 (Fed.
Cir. 2007). “The function, way, result inquiry focuses on an
examination of the claim and the explanation of it found in
the written description of the patent.” 

tions omitted).
    While the district court provided little analysis or sup-
port as to its determination of no infringement under the
doctrine of equivalents, “we review judgments, not
16      PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.




opinions.” Bruno Indep. Living Aids, Inc. v. Acorn Mobility
Servs., Ltd., 

, 1354 (Fed. Cir. 2005) (citing
Black v. Cutter Labs., 

, 297 (1956)). We must
therefore determine whether the record supports the dis-
trict court’s determination that no reasonable jury could
find that Donghee’s accused product infringes under the
doctrine of equivalents.
    The district court’s limited citations to the record in-
clude a report and testimony from Dr. Osswald admitting
that “Donghee’s flat die tool may offer improvements (e.g.,
independent wall thickness manipulation) over the blade
and roller cutting system of the Asserted Patents.” J.A. 387
¶ 36; see also J.A. 430–31 (“Q: So I believe in your reply
report you believe that Donghee’s flat die would offer some
improvements over cutting -- over other methods of cutting
where you maybe have a knife . . . A: Well, I mean, I say it
right there. Like, independent wall thickness manipula-
tion. That’s one.”). Further, Dr. Osswald referred to this
ability to control the wall thickness as “an invention” dis-
tinct from the asserted patents. J.A. 431.
     As such, Dr. Osswald conceded that Donghee’s prod-
ucts differed from the patented invention because
Donghee’s process allowed for the advantageous capability
of independent wall thickness manipulation resulting from
the way plastic is split. The question is whether Plastic
Omnium presented evidence that this conceded advantage
is an “insubstantial difference.” AquaTex 

(quoting Texas Instruments, Inc. v. Cypress Semi-
conductor Corp., 

, 1567 (Fed. Cir. 1996)).
     Plastic Omnium’s arguments and the patents’ written
descriptions tout uniform wall thickness as a feature of the
patents. In its opening brief, Plastic Omnium states that
its inventions “avoid[] the prior ‘drawback of having to po-
sition two extrusion heads and/or extruders capable of sim-
ultaneously producing two flat sheets, the thickness
uniformity and the production uniformity of which are
PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.         17



[required to be] constant from one sheet to another and at
any point on each of the sheets.’” Appellant Br. 11 (quoting
the ’812 patent col. 1 ll. 42–46) (emphasis added). Dr.
Osswald conceded that, in contrast, independent wall
thickness manipulation is an advantage of the Donghee
system. Plastic Omnium failed to present evidence as to
why the differences between the touted advantage of uni-
form wall thickness in the ’812 and ’921 patents and the
capability of independent wall thickness manipulation in
the accused product were insubstantial. See Appellant Br.
41–42; Appellant Reply Br. 22–23. Plastic Omnium there-
fore failed to demonstrate a genuine dispute of material
fact that would prevent the grant of summary judgment as
to the doctrine of equivalents.
                       CONCLUSION
     The district court’s grant of summary judgment of no
literal infringement was consistent with its Claim Con-
struction Order based on undisputed differences between
the asserted patents and the accused product. The district
court’s grant of summary judgment of no infringement un-
der the doctrine of equivalents was correct in light of the
conceded differences between the claimed process in the as-
serted patents and process of the accused product. Because
we affirm based on the “parison” limitations, we need not
reach the issue of whether Plastic Omnium preserved the
“preassembled structure” claim construction issue concern-
ing the ’812 patent. We grant Plastic Omnium’s pending
Motion to Withdraw U.S. Patent Nos. 7,166,253 and
9,399,327 (ECF No. 47).
                       AFFIRMED
                          COSTS
   Each party shall bear its own costs.
  United States Court of Appeals
      for the Federal Circuit
                  ______________________

PLASTIC OMNIUM ADVANCED INNOVATION AND
               RESEARCH,
             Plaintiff-Appellant

                             v.

DONGHEE AMERICA, INC., DONGHEE ALABAMA,
                   LLC,
           Defendants-Appellees
          ______________________

                        2018-2087
                  ______________________

    Appeal from the United States District Court for the
District of Delaware in No. 1:16-cv-00187-LPS, Chief Judge
Leonard P. Stark.
                 ______________________
CLEVENGER, Circuit Judge, dissenting.
     The majority frames the parties’ dispute as one focused
on the meaning of the term “extruded parison.” The major-
ity concludes, as the district court did, that such a dispute
cannot preclude summary judgment because the patentee
acted as his own lexicographer when he defined the term
“extruded parison” in one of the asserted patent specifica-
tions. According to the majority, the district court correctly
construed the term in accordance with the patentee’s defi-
nition, and then simply applied that construction to the ac-
cused device, which did not include the claimed parison. To
both the district court and the majority, the claimed ex-
truded parison cannot exist in Donghee’s process because
2        PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.




the plastic is cut inside of a “die,” contravening the district
court’s construction. But by blessing the district court’s
analysis, the majority commits the same error. Both rely
on Donghee’s nomenclature—the fact that its cutting struc-
ture is called a “die”—to find no infringement. That anal-
ysis elides the key factual dispute: Does Donghee’s accused
process have more than one die? The real dispute therefore
is not over an extruded parison and what it takes to create
one—in fact, the parties agree on that front—but is instead
over the term “die” and whether Donghee’s extrusion head
contains one. Plastic Omnium presented sufficient evi-
dence to create a material factual dispute over the struc-
ture of Donghee’s extrusion head, and I therefore
respectfully dissent from the majority’s decision.
                               I
    The patents at issue in this case claim an improvement
on the standard manufacturing process used to create plas-
tic motor-vehicle fuel tanks. U.S. Patent No. 6,866,812
(“the ’812 patent”), Abstract (“Process for manufacturing
hollow plastic bodies, especially motor-vehicle fuel tanks.”);
U.S. Patent No. 6,814,921 (“the ’921 patent), Abstract
(“Process for manufacturing a plastic fuel tank.”). Specifi-
cally, claim 1 of the ’812 patent discloses in relevant part
“[a] process of manufacturing a hollow body for receiving a
liquid, comprising the steps of: extruding a parison; cutting
through said parison so as to form two portions separated
by a cut . . . .” ’812 patent, col. 5, ll. 43–47. Claim 1 of the
’921 patent similarly recites in relevant part:
    A process for manufacturing plastic hollow bodies
    from two shells formed by molding, which are
    joined together, at least one shell being produced
    by compression-molding a portion of a plastic sheet
    . . . characterized in that it is applied to the manu-
    facture of a fuel tank and in the sheet is obtained
    in the same manufacturing line as the shell which
PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.            3



    will be produced from this sheet, by the cutting and
    opening an extruded parison of closed cross section.
’921 patent, col. 5 ll. 44–col. 6 ll. 5.
    The patentee defined the term “extruded parison” in
the ’812 patent as “the product obtained by passing,
through a die, a composition of at least one thermoplastic
melt homogenized in an extruder whose head is terminated
by the die.” ’812 patent, col. 2, ll. 35–40. In its Markman
order, the district court construed “extruded parison” con-
sistent with the ’812 patent’s definition as “a tubular pre-
form with a closed cross-section that has been forced
through a die, and is cut or split as it exits the die or at
some time thereafter.” J.A. 946. The district court ex-
plained further that, while the claimed process could not
“include[] the splitting of molten plastic within the extru-
sion head/die,” splitting could occur “right as the previously
tubular structure leaves the die/extrusion head.” J.A. 948.
The district court was never asked to construe the “die”
term, but in its Markman order, the district court disa-
greed with Plastic Omnium’s argument that the parison-
creating die could be located anywhere within the extru-
sion head because “[b]oth patents specify that the ‘die’ is
located at the ‘extrusion head[’s] lowest point.” J.A. 948 n.4
(quoting ’921 patent, col. 3, ll. 4–5).
     Besides the location of the die as either “mounted on
the extrusion head,” “located at the lowest point” of “the
extrusion head,” ’921 patent, col. 3, ll. 4–5, or being what
“terminate[s]” the head of the extruder, ’812 patent, col. 2,
ll. 37–38, the specification is mostly silent on its structure
and function. The specifications of both the ’921 and ’812
patents do, however, describe the die as “circular.” ’921 pa-
tent, col. 3, ll. 4–5.
                                II
    By the Markman hearing, Plastic Omnium was already
teeing up its argument that, in addition to Donghee’s flat
4        PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.




die tool, Donghee’s process involved another die at the bot-
tom of its extrusion head, or “coextrusion die tool,” as
Donghee refers to it in its literature. J.A. 711. During the
hearing, Plastic Omnium told the district court judge “[i]t
probably bears mentioning, I don’t know if it was apparent
in the briefing what the real dispute is between the parties
here, and I think what Donghee may say is they don’t have
a circular die. I think that’s where the dispute is going to
be.” J.A. 1523.
    Then, in its summary judgment briefing, Plastic Om-
nium supported its argument with its expert report that
identified the relevant die at the bottom of Donghee’s coex-
trusion die tool:
    The coextrusion die’s bottom includes the spiral
    mandrel and an outer body that surrounds the spi-
    ral mandrel, which together define an annular
    channel through which the extruded materials are
    forced to obtain the tubular preform. The structure
    that forms this annular channel, through which
    the molten material is forced before exiting the bot-
    tom of the coextrusion die, is a “die” as that term is
    used in general and as it is used in the asserted Pa-
    tents.
J.A. 264. Plastic Omnium’s expert made clear that he was
not “argu[ing] that some amorphous melt inside of
Donghee’s extrusion equipment is a parison.” J.A. 383. In-
stead, he was arguing that a parison is the tubular preform
created by the die at the bottom of Donghee’s coextrusion
die tool, which is fed into Donghee’s flat die tool, where the
extruded parison is cut. 

also pointed the district court to
Donghee’s own documentation, which stated that the “in-
let” to its flat die tool is a “round 6-layers [sic] parison,” and
that the flat die tool functions to “cut[] . . . the parison in
two halves.” J.A. 738. Thus, Plastic Omnium’s argument
all along was that Donghee’s flat die tool is essentially
PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.             5



irrelevant to the infringement analysis. What mattered,
Plastic Omnium explained, was that Donghee’s extrusion
head included a parison-creating die at its terminus, and
therefore “the plastic exiting Donghee’s coextrusion die
(with the spiral mandrel), and which is fed into the flat die
tool, is the claimed parison.” J.A. 383. Because the claimed
parison is formed in Donghee’s process and cut thereafter,
Plastic Omnium argued that Donghee clearly infringed the
claims of the ’812 and ’921 patents, as construed by the dis-
trict court.
     In its summary judgment opinion, the district court
clearly recognized that there was a dispute over whether
Donghee’s coextrusion head “is or has a die.” J.A. 19. Yet,
it granted summary judgment of noninfringement without
ever considering Plastic Omnium’s double-die argument.
It reasoned that there can be no literal infringement be-
cause “the splitting of the molten plastic must not occur in-
side any of the extrusion head/die equipment,” and it was
“undisputed that the extruded plastic parison is [] cut in a
separate flat die tool after it leaves Donghee’s coextrusion
die.” J.A. 20 (internal quotation marks omitted).
     The error that the district court committed, and that
the majority approves, stems from the assumption that the
relevant die for purposes of infringement is Donghee’s flat
die tool. Both rely on Donghee’s chosen nomenclature for
its cutting tool, i.e., “flat die tool,” to find that Donghee’s
process involves cutting molten plastic inside of a “die,” in-
stead of upon or after extrusion from the “die.” Because the
claims require cutting a parison, and a parison cannot be
cut before it is formed by being forced through a die, the
district court and the majority believe that there cannot ex-
ist the claimed parison in Donghee’s process. But just be-
cause Donghee calls its cutting tool a “die” does not mean
it is the relevant die for purposes of the infringement anal-
ysis.
6       PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.




    The only die that matters under the district court’s con-
struction of “extruded parison” is the die through which the
plastic is forced to form a parison. The district court’s con-
struction never required that such a die be the only die in
the process or the last die in the process. The fact that the
district court’s construction does not contemplate splitting
the tubular preform before it is at least partially extruded
from a die at the end of an extrusion head does not support
the broader conclusion, adopted by the majority, that the
patents require the tubular preform to be partially ex-
truded outside of all of the extrusion equipment, including
Donghee’s flat die tool, before being cut. Thus, if Plastic
Omnium is correct that Donghee’s accused process includes
an extrusion head that is terminated by a die, then such a
structure, under the court’s construction, would be suffi-
cient to create the claimed parison. Further, that parison
would be split by the flat die tool, which is outside of the
relevant extrusion head/die equipment, in keeping with the
district court’s construction.
    The majority discredits the evidence in support of Plas-
tic Omnium’s double die theory by relying on the fact that
the patentee acted as his own lexicographer when using the
“parison” term. According to the majority, the fact that
Donghee’s documentation refers to the plastic extruded
from Donghee’s extrusion head as a “parison” does not
mean that Donghee intended to use that word as it is used
in the patents. But the majority misunderstands how the
patentee changed the meaning of “parison” by defining it
in the ’812 specification.
    There was no disagreement between the parties here
that the “ordinary and customary” meaning of “parison” is
“a hollow plastic tube exiting the die of an extrusion head.”
J.A. 946. The district court determined, however, that the
’921 and ’812 patents do not use “parison” in the ordinary
sense. The district court found convincing Plastic Om-
nium’s argument that, while traditionally a parison is a
“plastic test-tube like structure” “formed outside of the
PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.            7



extrusion head/die,” the parison described in the ’921 and
’812 patents cannot be formed entirely outside of the extru-
sion head/die because the parison described in the patents
is split or cut into two sheets of plastic as it is being ex-
truded. J.A. 947. Thus, the district court’s construction did
nothing to undermine the plain and ordinary meaning of
the term “parison” insofar as the term refers to something
that is formed by exiting the die of an extrusion head. In-
stead, the construction clarified that the term in the con-
text of the patent could refer to a tubular preform structure
that exists only momentarily after exiting the die at the
bottom of the extrusion head, but before being split in two
sheets by the blades placed at the exit of the die. The ma-
jority is therefore wrong to discount the Donghee’s docu-
mentation supporting Plastic Omnium’s argument because
both the patent and a person of ordinary skill in the art use
the term to refer to a structure that is created when molten
plastic exits a die at the end of an extrusion head.
    Moreover, the fact that the patentee acted as his own
lexicographer does nothing to undermine Plastic Omnium’s
double die argument. In defining “extruded parison,” the
patentee never limited the mechanisms by which the
claimed parison can be cut. Further, in construing “ex-
truded parison,” the court put no restrictions on where or
how the parison must be cut, only that it occur “as [the par-
ison] exits the die or at sometime thereafter.” J.A. 946.
Nothing prevents the claimed parison, under the district
court’s construction and the patent’s definition, from being
cut within a structure such as Donghee’s flat die tool, so
long as it is created by a die before it is cut. Under Plastic
Omnium’s double die argument, a parison would be created
by the die at the bottom of Donghee’s coextrusion die tool,
satisfying that requirement.
                             III
    The district court took its eye off the ball. It knew for
sure that the big question in this case is whether Donghee’s
8       PLASTIC OMNIUM ADVANCED v. DONGHEE AMERICA, INC.




accused structure includes a separate die that creates an
extruded parison which is cut after it emerges from the ex-
trusion die. And we have to assume it knew about the evi-
dence from Plastic Omnium’s expert (Dr. Osswald), whose
credibility and credentials are unchallenged. Dr. Osswald
pointed to the spiral mandrel at the bottom of Donghee’s
extrusion head as the die that creates the extruded parison
which is cut in Donghee’s flat tie tool. Donghee may disa-
gree with Dr. Osswald, but by any count, the district court
left unresolved a material factual dispute over the struc-
ture of Donghee’s accused device, a material factual dis-
pute the majority is unwilling to confront. The district
court deprived Plastic Omnium of its day in court, and the
majority perpetuates that error.
    A material factual dispute prevents summary judg-
ment. See Dorel Juvenile Grp., Inc. v. Graco Children's
Prod., Inc., 

, 1047 (Fed. Cir. 2005) (vacating
grant of summary judgment of noninfringement because a
material factual dispute existed over how the accused prod-
uct functioned); Hilgraeve Corp. v. McAfee Assocs., Inc., 

, 1353 (Fed. Cir. 2000) (“These differences in the
experts’ descriptions of [the allegedly infringing process’s]
operation raise a genuine issue of material fact.”). This
court should vacate the district court’s summary judgment
of noninfringement, and remand the case for resolution of
the dispositive material factual dispute.