Court Opinion

ID: 3214292
Source: CourtListenerOpinion
Date Created: 2016-06-17 15:01:26.458242+00
Date Added: 2024-06-11T14:46:00.318229
License: Public Domain

NOTE: This disposition is nonprecedential.

   United States Court of Appeals
       for the Federal Circuit
                        ______________________

  GRAFTECH INTERNATIONAL HOLDINGS, INC.,
                Appellant

                                       v.

                LAIRD TECHNOLOGIES INC.,
                           Appellee
                    ______________________

                              2015-1796
                        ______________________

    Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in No. IPR2014-
00023.

---------------------------------------------------------------------------------

  GRAFTECH INTERNATIONAL HOLDINGS, INC.,
                Appellant

                                       v.

                LAIRD TECHNOLOGIES, INC.,
                           Appellee
                    ______________________

                         2015-1797, 2015-1798
                        ______________________
2          GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.

   Appeals from the United States Patent and Trade-
mark Office, Patent Trial and Appeal Board in Nos.
IPR2014-00024 and IPR2014-00025.
               ______________________

                  Decided: June 17, 2016
                  ______________________

    ERIN M. DUNSTON, Buchanan Ingersoll & Rooney PC,
Alexandria, VA, argued for appellant. Also represented
by TRAVIS WILLIAM BLISS, Wilmington, DE.

    MATTHEW L. CUTLER, Harness, Dickey & Pierce, PLC,
St. Louis, MO, argued for appellee.
                 ______________________

Before REYNA, CLEVENGER, and WALLACH, Circuit Judges.
WALLACH, Circuit Judge.
    Appellee Laird Technologies, Inc. (“Laird”) sought in-
ter parties review of various claims of U.S. Patent Nos.
6,482,520 (“the ’520 patent”), 6,982,874 (“the ’874 pa-
tent”), and 7,292,441 (“the ’441 patent”) (collectively, “the
patents-in-suit”) before the United States Patent and
Trademark Office’s Patent Trial and Appeal Board
(“PTAB”). In separate Final Written Decisions, the PTAB
found the disputed claims of the patents-in-suit invalid as
obvious. See Laird Techs., Inc. v. GrafTech Int’l Holdings,
Inc. (GrafTech I), No. IPR2014-00023, 2015 WL 1385390
(P.T.A.B. Mar. 25, 2015) (addressing the ’520 patent);
Laird Techs., Inc. v. GrafTech Int’l Holdings, Inc.
(GrafTech II), No. IPR2014-00024, 2015 WL 1385391
(P.T.A.B. Mar. 25, 2015) (addressing the ’874 patent);
Laird Techs., Inc. v. GrafTech Int’l Holdings, Inc.
(GrafTech III), No. IPR2014-00025, 2015 WL 1385392
(P.T.A.B. Mar. 25, 2015) (addressing the ’441 patent).
Appellant GrafTech International Holdings, Inc.
GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.           3

(“GrafTech”) appeals the PTAB’s decisions.           For the
reasons provided below, we affirm.
                         DISCUSSION
  I. Subject Matter Jurisdiction and Standard of Review
    We possess subject matter jurisdiction over
GrafTech’s appeals pursuant to 28 U.S.C. § 1295(a)(4)(A)
(2012). We review the PTAB’s legal conclusions de novo,
In re Elsner, 381 F.3d 1125, 1127 (Fed. Cir. 2004), and its
factual findings for substantial evidence, In re Gartside,
203 F.3d 1305, 1316 (Fed. Cir. 2000). “Substantial evi-
dence” constitutes the evidence that a reasonable mind
would accept to support a finding. See Consol. Edison Co.
v. NLRB, 305 U.S. 197, 229 (1938).
II. The PTAB Properly Found the Disputed Claims of the
                 ’520 Patent Obvious
    A patent claim would have been obvious and therefore
invalid “if the differences between the subject matter
sought to be patented and the prior art are such that the
subject matter as a whole would have been obvious at the
time the invention was made to a person having ordinary
skill in the art [(‘PHOSITA’)] to which said subject matter
pertains.” 35 U.S.C. § 103(a) (2006). 1 Obviousness is a
question of law based on underlying findings of fact.
Gartside, 203 F.3d at 1316. The underlying factual find-
ings include (1) “the scope and content of the prior art,”
(2) “differences between the prior art and the claims at
issue,” (3) “the level of ordinary skill in the pertinent art,”

    1    In passing the Leahy-Smith America Invents Act
(“AIA”), Congress amended § 103. Pub. L. No. 112-29,
§ 3(c), 125 Stat. 284, 287–88 (2011). However, because
the application that led to the ’520 patent was filed before
March 16, 2013, the pre-AIA § 103 applies. Id., § 3(n)(1),
125 Stat. at 293.
4          GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.

and the presence of (4) secondary considerations of non-
obviousness such “as commercial success, long-felt but
unsolved needs, [and] the failure of others.” Graham v.
John Deere Co. of Kan. City, 383 U.S. 1, 17–18 (1966).
    The PTAB found claims 1, 2, and 21–23 of the ’520 pa-
tent obvious over various prior art references. GrafTech I,
2015 WL 1385390, at *8–15. It also found evidence as to
secondary considerations did not warrant the opposite
result. Id. at *15–19. GrafTech challenges these findings
and alleges that the PTAB afforded undue weight to
testimony from Laird’s expert witness, William Bagot, in
reaching its conclusions. We address each argument in
turn.
                    A. The ’520 Patent
     The ’520 patent “relates to a system effective for dis-
sipating the heat generated by an electronic component
using a thermal management system that includes a
thermal interface formed from a flexible graphite sheet
and/or a heat sink formed from a graphite article.” ’520
patent, Abstract. 2 The invention seeks to dissipate heat
generated from increasingly “sophisticated electronic
components . . . having smaller size and more complicated
power requirements . . . ,” such as microprocessors. Id.
col. 1. ll. 12–20. Independent claim 1 is representative
and recites:
    A thermal management system comprising a heat
    source having an external surface and an aniso-
    tropic flexible graphite sheet formed of com-
    pressed particles of exfoliated natural graphite
    and having a planar area greater than the area of

    2   After the ’520 patent issued in 2002, its claims
were amended in 2007 and 2009, respectively, as a result
of separate ex parte reexaminations. Where appropriate,
we cite the ’520 patent’s claims as amended.
GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.         5

    the external surface of the heat source, the flexi-
    ble graphite sheet having first and second major
    planar surfaces and having axes of higher thermal
    conductivity parallel to said major planar surfaces
    such that the ratio of thermal conductivity of the
    flexible graphite sheet parallel to said major pla-
    nar surfaces to the thermal conductivity of the
    flexible graphite sheet transverse to said major
    surfaces is at least about 20, one of said major
    planar surfaces being in direct operative contact
    with the heat source.
J.A.-1796, at 144 (’520 patent First Ex Parte Reexamina-
tion Certificate), col. 1 ll. 26–40. 3 Dependent claim 2
limits the “heat source” recited in claim 1 to “an electronic
component.” ’520 patent col. 13 l. 67. Claims 21–23
depend from claim 1 and provide additional limitations to
the graphite sheet used in the invention. J.A.-1796, at
144 (’520 patent First Ex Parte Reexamination Certifi-
cate), col. 2 ll. 30–39. The central issues in this appeal
concern the graphite sheet claimed in the ’520 patent.
B. The PTAB Properly Found that the Prior Art Renders
    Obvious the Disputed Claims of the ’520 Patent
    The PTAB concluded that claims 1, 2, 22, and 23 of
the ’520 patent would have been obvious over Japanese
Laid-Open Patent Application No. H10-56114 (“Inoue”),
J.A.-1796, at 1384–97, in view of the Grafoil Engineering
Design Manual (“Grafoil Manual”), J.A.-1796, at 1192–
1280. GrafTech I, 2015 WL 1385390, at *8–14. The
PTAB also found claim 21 obvious over Inoue in view of

    3   The suffix -1796 denotes the materials in Appeal
No. 2015-1796, while the suffix -1797 denotes those in
Appeal Nos. 2015-1797 and -1798. In July 2015, the court
consolidated Appeal Nos. 2015-1797 and -1798 and desig-
nated Appeal No. 2015-1796 as a companion case.
6         GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.

the Grafoil Manual and an entry from the Thermagon,
Inc. website (“Thermagon Paper”), J.A.-1796, at 1374–75.
GrafTech I, 2015 WL 1385390, at *14–15. GrafTech
challenges the PTAB’s findings.
    GrafTech first alleges that a PHOSITA “would not
have been motivated to combine Inoue with the Grafoil
Manual,” such that the PTAB erred in finding claims 1, 2,
22, and 23 of the ’520 patent obvious. Appellant’s Br.-
1796, at 4, 32 (capitalization omitted). This is so,
GrafTech argues, because Inoue requires the use of a
carbonaceous sheet with a thermal conductivity higher
than that of copper or aluminum, id. at 29–31, and the
Grafoil Manual does not disclose a sheet with such prop-
erties, id. at 31–32. 4 GrafTech argues that this discrep-
ancy demonstrates that a PHOSITA would not expect
success in combining the references. Id. at 34–35.
    As part of the obviousness inquiry, we consider
“whether a [PHOSITA] would have been motivated to
combine the prior art to achieve the claimed invention
and whether there would have been a reasonable expecta-
tion of success in doing so.” DyStar Textilfarben GmbH &
Co. Deutschland KG v. C.H. Patrick Co., 464 F.3d 1356,
1360 (Fed. Cir. 2006) (citation omitted). The answers to
these questions require producing factual findings that we
review for substantial evidence. Gartside, 203 F.3d at
1316.
    Substantial evidence supports the PTAB’s finding
that a motivation existed to combine Inoue with the

    4   According to GrafTech, the “in-plane thermal con-
ductivity of copper is 400 [watts per meter kelvin
(‘W/m∙K’)] and that of aluminum is 200 W/m∙K,” whereas
the thermal conductivity of the graphite sheets in the
Grafoil Manual “is but 140 W/m∙K.” Appellant’s Br.-1796,
at 3.
GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.         7

Grafoil Manual and that a PHOSITA would have a rea-
sonable expectation of success in combining the refer-
ences. GrafTech’s argument rests on the premise that a
PHOSITA would not have been motivated to combine
Inoue with the Grafoil Manual because doing so would not
yield an invention that meets the thermal conductivity
requirement allegedly found in Inoue, which does not
appear in the disputed claims of the ’520 patent. ’520
patent col. 13 ll. 66–67 (claim 2); J.A.-1796, at 144 (’520
patent First Ex Parte Reexamination Certificate), col. 1 ll.
26–40 (claim 1), col. 2 ll. 30–39 (claims 21–23). The PTAB
held that Inoue does not require the use of a carbonaceous
sheet with a thermal conductivity higher than that of
copper or aluminum, but instead found that “a person of
skill in the relevant technology . . . would have the requi-
site skill and creativity to select the appropriate graphite
material for the task at hand.” GrafTech I, 2015 WL
1385390, at *12. The record supports this conclusion
because Inoue discloses a carbonaceous sheet with a
thermal conductivity higher than that of copper or alumi-
num in its description of one preferred embodiment and
does not make it a requirement. J.A.-1796, at 1386–87
¶¶ 6, 8 (Inoue), 4848 (GrafTech acknowledging that “[t]he
word[] ‘must’ [is] not in either [of the relevant paragraphs
of Inoue].” (emphasis added)). An obviousness inquiry is
not limited to the prior art’s preferred embodiment. See,
e.g., Pfizer, Inc. v. Apotex, Inc., 480 F.3d 1348, 1370 (Fed.
Cir. 2007).
     GrafTech next avers that substituting the carbona-
ceous sheet disclosed in Inoue with the graphite sheet in
the Grafoil Manual would yield an inoperable product,
such that the PTAB erred in finding that a PHOSITA
would be motivated to combine them. Appellant’s Br.-
1796, at 34–37. GrafTech did not raise this argument
before the PTAB, see J.A.-1796, at 1760–1843 (GrafTech’s
Response), and accordingly GrafTech has waived it, see,
e.g., Redline Detection, LLC v. Star Envirotech, Inc., 811
8          GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.

F.3d 435, 450 (Fed. Cir. 2015) (explaining that the court
does not consider arguments not raised before the PTAB).
    GrafTech further argues that the PTAB “fell into the
hindsight trap” in reaching its obviousness conclusion
because it allegedly relied upon “modern evidence” in
reaching its conclusion that the prior art does not teach
away from the disputed claims of the ’520 patent. Appel-
lant’s Br.-1796, at 38 (capitalization altered). According
to GrafTech, the PTAB “impermissibly used knowledge of
GrafTech’s actual invention in its obviousness inquiry.”
Id. at 39 (citation omitted); see also id. at 39–43 (raising
related arguments).
     “A reference may be said to teach away when a person
of ordinary skill, upon reading the reference, would be
discouraged from following the path set out in the refer-
ence, or would be led in a direction divergent from the
path that was taken by the applicant.” Galderma Labs.,
L.P. v. Tolmar, Inc., 737 F.3d 731, 738 (Fed. Cir. 2013)
(citation omitted). In assessing whether prior art teaches
away from the claimed invention, the PTAB may consider
“only knowledge which was within the level of ordinary
skill in the art at the time the claimed invention was
made,” but may not consider the claimed invention itself.
In re McLaughlin, 443 F.2d 1392, 1395 (CCPA 1971).
Whether a reference teaches away presents a factual
question reviewed for substantial evidence. Gartside, 203
F.3d at 1316.
    GrafTech argued that the graphite sheets disclosed in
the disputed claims of the ’520 patent would not meet the
thermal conductivity requirement allegedly required by
Inoue, such that Inoue teaches away from the claims of
the ’520 patent. See GrafTech I, 2015 WL 1385390, at
*11. However, the PTAB observed that a skilled artisan
would be able to select the appropriate graphite for the
particular application, including the products in the
Grafoil Manual that were available at the time and satis-
GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.        9

fy the relevant claim elements. Id. at *12. As a result, we
disagree with GrafTech that the PTAB’s analysis rested
on impermissible hindsight.
     Finally, as to claim 21 of the ’520 patent, GrafTech
argues that the “Thermagon Paper does not remedy the
inoperative result of combining Inoue with the Grafoil
Manual.” Appellant’s Br.-1796, at 4, 43 (capitalization
omitted). As discussed above, GrafTech did not present
this argument before the PTAB and, thus, has waived any
argument that combining Inoue with the Grafoil Manual
would yield an inoperable result. In any event, the PTAB
did not cite the Thermagon Paper to remedy a problem
that would arise in combining Inoue with the Grafoil
Manual. Instead, the PTAB observed that the Thermagon
Paper teaches the limitation of claim 21 of the ’520 pa-
tent, GrafTech I, 2015 WL 1385390, at *14–15, which
requires that “the contact pressure between the flexible
graphite sheet and the heat source is less than 50 [pounds
per square inch].” J.A.-1796, at 144 (’520 patent First Ex
Parte Reexamination Certificate), col. 2 ll. 30–32 (claim
21).
 C. Substantial Evidence Supports the PTAB’s Findings
       With Respect to Secondary Considerations
    A party may counter an obviousness challenge by
demonstrating that, inter alia, “the commercial success of
[a] product results from the claimed invention.” J.T.
Eaton & Co. v. Atl. Paste & Glue Co., 106 F.3d 1563, 1571
(Fed. Cir. 1997) (emphasis added). The PTAB considered
the evidence as to commercial success, among other
objective indicia of non-obviousness, 5 and determined that

    5   Notably, GrafTech does not challenge the PTAB’s
findings as to the other objective indicia of non-
obviousness—i.e., industry praise, failure of others, and
copying. See generally Appellant’s Br.-1796. Thus, even if
10        GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.

none of the evidence established a nexus with the subject
matter claimed in the ’520 patent. GrafTech I, 2015 WL
1385390, at *15–19. GrafTech challenges the PTAB’s
conclusions as to commercial success. Appellant’s Br.-
1796, at 46–56.
    GrafTech alleges that, in finding no nexus existed be-
tween the evidence of commercial success and the disput-
ed claims of the ’520 patent, the PTAB confused
“GrafTech’s arguments about the teachings of the cited
[prior] art, specifically the Grafoil® Manual, with
GrafTech’s evidence of the commercial-successfully
[graphite sheet] being employed today.” Appellant’s Br.-
1796, at 47–48. GrafTech also asserts that it “established
the required nexus between the claimed invention and the
evidence of commercial success,” id. at 51 (capitalization
omitted), citing revenues for products such as the Apple
iPhone and the Amazon Kindle Fire HD, id. at 52–54.
    We agree with GrafTech that the PTAB applied an in-
correct analysis in assessing commercial success.
GrafTech properly notes that the PTAB compared the
teachings of the prior art to evidence of commercial suc-
cess, instead of comparing the requirements of the disput-
ed claims of the ’520 patent to evidence of commercial
success. See GrafTech I, 2015 WL 1385390, at *16–18.
The appropriate standard teaches that “[e]vidence of
commercial success . . . is only significant if there is a
nexus between the claimed invention and the commercial
success.” Ormco Corp. v. Align Tech., Inc., 463 F.3d 1299,
1311–12 (Fed. Cir. 2006) (emphasis added). “When a

GrafTech demonstrated reversible error as to commercial
success, that error would not disturb the substantial
evidence supporting the PTAB’s conclusion that the other
objective indicia of non-obviousness “do[] not tip the
balance in favor of [GrafTech].” GrafTech I, 2015 WL
1385390, at *19.
GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.      11

patentee can demonstrate commercial success, usually
shown by significant sales in a relevant market, and that
the successful product is the invention disclosed and
claimed in the patent, it is presumed that the commercial
success is due to the patented invention.” J.T. Eaton, 106
F.3d at 1571 (citation omitted). The patentee bears the
initial burden of demonstrating that the requisite nexus
exists. See id. Whether the requisite nexus exists raises
a factual question that we review for substantial evidence.
See Gartside, 203 F.3d at 1316.
    GrafTech failed to meet its burden of demonstrating
the requisite nexus. First, GrafTech submitted the same
evidence in each of the inter partes reviews to establish
the commercial success of the patents-in-suit. Compare
Appellant’s Br.-1796, at 45–65, with Appellant’s Br.-1797,
at 62–80. That strategy undermines its commercial
success arguments because GrafTech argues that the
patents-in-suit are directed to different inventions. See
infra Section III.A; Ormco Corp., 463 F.3d at 1311–12
(explaining that a nexus must exist “between the claimed
invention and the commercial success” (emphasis added)).
Second, GrafTech does not assert that the commercial
success of products like the Apple iPhone and the Amazon
Kindle Fire HD resulted from the products covered by the
’520 patent or that the products covered by the ’520
patent are coextensive with the Apple iPhone and Ama-
zon Kindle Fire HD; instead, GrafTech asserts that the
Apple iPhone and Amazon Kindle Fire HD used products
covered by the ’520 patent and enjoyed commercial suc-
cess. Appellant’s Br.-1796, at 52–54. Evidence of the
latter is insufficient to demonstrate the requisite nexus.
See, e.g., Demaco Corp. v. F. Von Langsdorff Licensing
Ltd., 851 F.2d 1387, 1392 (Fed. Cir. 1988) (“When the
thing that is commercially successful is not coextensive
with the patented invention . . . [,] the patentee must
show prima facie a legally sufficient relationship between
that which is patented and that which is sold.” (emphasis
12        GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.

added)); see also Ormco Corp., 463 F.3d at 1311–12 (ex-
plaining that a nexus must exist “between the claimed
invention and the commercial success” (emphasis added)).
D. Substantial Evidence Supports the PTAB’s Decision to
           Rely upon Mr. Bagot’s Testimony
    The PTAB relied upon the testimony of Mr. Bagot
throughout its obviousness analysis. See GrafTech I, 2015
WL 1385390, at *10–15. GrafTech contends that the
PTAB “erred in relying upon the testimony of Mr. Bagot
and failed to act as an impartial adjudicator.” Appellant’s
Br.-1796, at 59 (capitalization omitted). 6 “Because Mr.
Bagot is not an expert in the pertinent art,” GrafTech
continues, the PTAB “failed to uphold its ‘gatekeeping’
role.” Id. GrafTech clarifies in its reply that it contests
“the weight to be afforded Mr. Bagot’s opinions, not their
admissibility.” Appellant’s Reply-1796, at 29 (citation
omitted).
    GrafTech’s argument suffers from two flaws. First,
GrafTech’s argument asks us to reweigh the evidence,
which we may not do under the substantial evidence
standard of review. See In re NTP, Inc., 654 F.3d 1279,
1292 (Fed. Cir. 2011) (explaining that, under the substan-
tial evidence standard of review, “[t]his court does not
reweigh evidence on appeal, but rather determines
whether substantial evidence supports the [PTAB’s] fact
findings”); Nutrinova Nutrition Specialties & Food Ingre-

     6   Laird alleges that GrafTech has waived this ar-
gument by failing to raise it below. Appellee’s Br.-1796,
at 43. However, Laird’s argument confuses the admissi-
bility of the testimony with the weight afforded to such
testimony. The record indicates that GrafTech argued
that the PTAB should afford no weight to Mr. Bagot’s
testimony, just as it does on appeal. See J.A.-1796, at
1907.
GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.       13

dients GmbH v. Int’l Trade Comm’n, 224 F.3d 1356, 1359
(Fed. Cir. 2000) (“Even if we might have found some of
the facts differently, or even if we might have drawn some
inferences from the facts differently, . . . that is not the
role of an appellate court.”). Second, the record does not
support GrafTech’s argument. During cross-examination,
Mr. Bagot testified that he worked extensively with
graphite and that his education in Britain is equivalent to
a bachelor’s degree in science engineering in the United
States. J.A.-1796, at 2579–80. Mr. Bagot also testified
that he possesses over five years of experience in thermal
management and electronics and that he has worked with
flexible graphite sheets for over five years. J.A.-1796, at
2581–82. These are the qualifications that GrafTech
alleged an individual should possess to qualify as an
expert. See GrafTech I, 2015 WL 1385390, at *5. Thus,
substantial evidence supports the PTAB’s decision to rely
upon Mr. Bagot’s testimony.
 III. GrafTech Does Not Demonstrate PTAB Error as to
               the ’874 and ’441 Patents
    The PTAB gives “[a] claim . . . its broadest reasonable
construction in light of the specification of the patent in
which it appears.” 37 C.F.R. § 42.100(b) (2015). 7 A speci-

    7   In In re Cuozzo Speed Techs., LLC, the Supreme
Court is considering whether the PTAB “may construe
claims in an issued patent according to their broadest
reasonable interpretation rather than their plain and
ordinary meaning.” Brief for Petitioner at *II, In re
Cuozzo Speed Techs., LLC (No. 15-446), 2016 WL 737452
(Feb. 22, 2016). Even if the Supreme Court finds that the
PTAB should construe terms consistent with their plain
and ordinary meaning, that holding would not change our
conclusion in this case because GrafTech’s proffered
construction improperly would impose an extraneous
limitation on the disputed claims, as discussed below.
14         GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.

fication “includes both the written description and the
claims” of the patent in question. In re Packard, 751 F.3d
1307, 1320 n.11 (Fed. Cir. 2014). If a specification does
not assign or suggest a particular definition to a claim
term, and the PTAB relies upon evidence extrinsic to the
specification to construe a claim, “[w]e review [the] under-
lying factual determinations concerning extrinsic evidence
for substantial evidence and the ultimate construction of
the claim de novo.” In re Cuozzo Speed Techs., LLC, 793
F.3d 1268, 1280 (Fed. Cir. 2015) (citation omitted), cert.
granted sub nom., Cuozzo Speed Techs., LLC v. Lee, 136 S.
Ct. 890 (2016).
     In separate decisions, the PTAB found claims 1–20 of
the ’874 patent and claims 1–16 of the ’441 patent would
have been obvious over various prior art references.
GrafTech II, 2015 WL 1385391, at *2 (addressing the ’874
patent); GrafTech III, 2015 WL 1385392, at *2 (address-
ing the ’441 patent). Before making its obviousness
determinations, the PTAB construed “thermal shielding”
in independent claims 1 and 11 of the ’874 patent and
independent claim 1 of the ’441 patent to mean “a struc-
ture that protects against heat.” GrafTech II, 2015 WL
1385391, at *10 (addressing the ’874 patent); GrafTech
III, 2015 WL 1385392, at *10 (addressing the ’441 patent)
(explaining that “thermal shielding” means “protection
against heat”). Because the specification does not define
“shield,” the PTAB relied upon a dictionary definition to
construe “thermal shielding.” GrafTech II, 2015 WL
1385391, at *10 (addressing the ’874 patent); GrafTech
III, 2015 WL 1385392, at *10 (addressing the ’441 patent).
    GrafTech challenges the PTAB’s construction of
“thermal shielding” in the ’874 and ’441 patents. Appel-
lant’s Br.-1797, at 39–48. Because of that allegedly
erroneous construction, GrafTech avers, the PTAB’s
obviousness determinations are necessarily defective. Id.
at 49 (The “erroneous construction of ‘thermal shield’
caused the [PTAB] to conclude that the challenged claims
GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.       15

[would have been] obvious.” (emphasis added) (capitaliza-
tion omitted)). We address each argument in turn.
               A. The ’874 and ’441 Patents
    The ’874 and ’441 patents relate generally to a “ther-
mal solution for an electronic device, which is positioned
between a heat source and an external surface of the
electronic device and/or another component of the elec-
tronic device.” 8 ’874 patent, Abstract; ’441 patent, Ab-
stract (explaining that the invention relates to a “thermal
solution for a portable electronic device [(i.e., a cell
phone)], which is positioned between a heat source and
another component of the electronic device” (emphasis
added)). The inventions covered by the ’874 and ’441
patents “facilitate[] heat dissipation from the heat source
while shielding the external surface and/or second compo-
nent from the heat generated by the heat source.” ’874
patent, Abstract; ’441 patent, Abstract (explaining that
the invention “facilitates heat dissipation from the heat
source while shielding the second component from the
heat generated by the heat source”).
    Independent claims 1 and 11 are representative of the
’874 patent. Independent claim 1 recites:
    A thermal dissipation and shielding system for an
    electronic device, comprising:

    8    The patent application that matured into the ’441
patent was originally filed as a continuation-in-part of the
application that resulted in the ’874 patent. “[A] continu-
ation-in-part application contain[s] a portion or all of the
disclosure of an earlier application together with added
matter not present in that earlier application.” PowerOa-
sis, Inc. v. T-Mobile USA, Inc., 522 F.3d 1299, 1304 n.3
(Fed. Cir. 2008) (citation omitted).
16         GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.

        an electronic device comprising a first compo-
        nent which comprises a heat source, wherein
        the first component transmits heat to an ex-
        ternal surface of the electronic device;
        a thermal solution comprising two major sur-
        faces, the thermal solution positioned such
        that one of its major surfaces is in operative
        contact with the first component such that it
        is interposed between the first component and
        the external surface of the electronic device,
     wherein the thermal solution comprises at least
     one sheet of compressed particles of exfoliated
     graphite which thermally shields the external sur-
     face of the electronic device from heat generated
     by the first component.
’874 patent col. 16 ll. 32–46 (emphases added). Independ-
ent claim 11 is similar to claim 1, but also requires a
“second component,” and further requires the graphite
sheet disclosed in claim 1 to be interposed between the
first and second components. Id. col. 17 ll. 9–21; see also
J.A.-1797, at 189 (Certificate of Correction addressing
Claim 11). Independent claim 1 is representative of the
’441 patent and recites:
     A thermal dissipation and shielding system for a
     cell phone, comprising:
        a cell phone comprising a first component
        which comprises a heat source and a second
        component to which the first component
        transmits heat;
        a thermal solution interposed between the
        first component and the second component,
     wherein the thermal solution comprises at least
     one sheet of compressed particles of exfoliated
     graphite which thermally shields the second com-
GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.         17

    ponent from heat generated by the first compo-
    nent.
’441 patent col. 16 l. 63–col. 17 l. 6 (emphases added).
B. The PTAB Properly Construed “Thermal Shielding” in
              the ’874 and ’441 Patents
     GrafTech contests the PTAB construction of “thermal
shielding.” As an initial matter, GrafTech raises several
arguments in its opening brief that it did not present to
the PTAB. See Appellant’s Br.-1797, at 39–48. “[W]e
have often barred parties from changing the scope of their
claim construction position on appeal” because, when an
appellant fails to make an argument to the PTAB, “we do
not have the benefit of the [PTAB’s] informed judgment
on this issue for our review.” In re Watts, 354 F.3d 1362,
1368 & n.3 (Fed. Cir. 2004) (citations omitted). Before the
PTAB, GrafTech limited its argument on the construction
of “thermal shielding” as follows:
    The [PTAB] utilizes a general dictionary defini-
    tion to define “shield” as “to cover and protect,”
    and to, in turn, define “thermally shields” or
    “thermal shielding” as “any structure that pro-
    tects against heat.” Though this definition is not
    entirely inaccurate, GrafTech submits that this
    definition is somewhat incomplete as it fails to
    take into account the description of thermal
    shielding from the specification and the accepted
    definition of a thermal shield within the art. The
    disclosure of the ’874 [p]atent demonstrates that
    thermal shielding is protection of a portion of the
    device other than the heat source itself from the
    heat generated by a heat source.
    Thus, GrafTech submits that the broadest reason-
    able interpretation of [“]thermally shields” or
    “thermal shielding” as used in the ’874 [p]atent is
18         GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.

     protection of a region other than the heat source
     itself from heat generated by the heat source.
J.A.-1797, at 1160–61 (citations omitted); see also J.A.-
1797, at 5314–15 (where GrafTech presents nearly identi-
cal arguments as to the construction of “thermal shield-
ing” in the ’441 patent). As a result, our analysis focuses
on the limited question of whether the PTAB erred by not
including the clause “other than the heat source itself”
when it construed “thermal shielding” to mean “a struc-
ture that protects against heat.” See Appellant’s Br.-
1797, at 40, 48 (where GrafTech presents the argument
that was raised before the PTAB).
    The PTAB’s construction of “thermal shielding” in
claims 1 and 11 of the ’874 patent and claim 1 of the ’441
patent does not suffer from error because adopting
GrafTech’s proffered construction would introduce an
extraneous limitation into the claims’ terms. “If we need
not rely on a [proffered] limitation to interpret what the
patentee meant by a particular term or phrase in a claim,
that limitation is ‘extraneous’ and cannot constrain the
claim.” Renishaw PLC v. Marposs Societa’ per Azioni, 158
F.3d 1243, 1249 (Fed. Cir. 1998) (citations omitted). The
challenged claims already explicitly require a graphite
sheet to shield a component other than the heat source
itself from the heat generated by that source. Specifically,
claim 1 of the ’874 patent requires a graphite sheet to
“shield[] the external surface of the electronic device from
the heat generated by the first component,” thus protect-
ing a portion of the device (external surface) that is not
the heat source (first component). ’874 patent col. 16 ll.
45–46. Claim 11 of the ’874 patent similarly requires a
graphite sheet to “shield[] [a second component] of the
electronic device from heat generated by the first
com[p]onent,” thus protecting a portion of the device
(second component) that is not the heat source (first
component). Id. col. 17 ll. 20–21. And claim 1 of the ’441
patent requires a graphite sheet to “shield[] the second
GRAFTECH INT’L HOLDINGS, INC. v. LAIRD TECHS. INC.      19

component from heat generated by the first component.”
’441 patent col. 17 ll. 5–6. Thus, we find no error in the
PTAB’s construction of the challenged claims.
C. The Court Need Not Address the PTAB’s Obviousness
     Determinations as to the ’874 and ’441 Patents
    GrafTech alleges that the “erroneous construction of
‘thermal shield’ [in the ’874 and ’441 patents] caused the
[PTAB] to conclude that the challenged claims [would
have been] obvious.” Appellant’s Br.-1797, at 49 (capitali-
zation omitted) (emphasis added). Because we conclude
that the PTAB did not err in its construction of “thermal
shield,” we need not address GrafTech’s conditional
arguments as to the PTAB’s obviousness determinations. 9
                        CONCLUSION
   We have considered GrafTech’s remaining arguments
and find them unpersuasive. Accordingly, the Final
Written Decisions of the United States Patent and
Trademark Office’s Patent Trial and Appeal Board are
                       AFFIRMED

    9   GrafTech challenges the PTAB’s analysis of com-
mercial success and the weight that the PTAB afforded to
Mr. Bagot’s testimony in finding the disputed claims of
the ’874 and ’441 patents invalid as obvious. It raises
arguments nearly identical to those that it raised in its
challenge to the PTAB’s obviousness determination as to
the ’520 patent. Compare Appellant’s Br.-1796, at 45–65,
with Appellant’s Br.-1797, at 62–80. We reject them for
the same reasons that we reject GrafTech’s appeal as to
the ’520 patent.