Global Tubing LLC v. Tenaris Coiled Tubes LLC, Tenaris S.a.

United States Court of Appeals
for the Federal Circuit
______________________
GLOBAL TUBING LLC,
Plaintiff-Cross-Appellant
v.
TENARIS COILED TUBES LLC, TENARIS S.A.,
Defendants-Appellants
______________________
2023-1882, 2023-1883
______________________
Appeals from the United States District Court for the
Southern District of Texas in No. 4:17-cv-03299, Judge
Keith P. Ellison.
______________________
Decided: February 26, 2026
______________________
J EFFREY A. L AMKEN, MoloLamken LLP, Washington,
DC, argued for plaintiff-cross-appellant. Also represented
by RAYINER HASHEM , WALTER H. HAWES , IV, CALEB HAYES -
D EATS , EUGENE ALEXIS SOKOLOFF ; J EFFREY A. ANDREWS ,
CHRISTOPHER J OHNSON, RICHARD P AUL YETTER , MATTHEW
ZORN, Yetter Coleman, LLP, Houston, TX.
J OHN C. O'Q UINN, Kirkland & Ellis LLP, Washington,
DC, argued for defendants-appellants. Also represented by
WILLIAM H. BURGESS , ASHLEY CADE, ERIN E LIZABETH CADY ,
ANNIE CHIANG, MEGAN M CG LYNN BUTLER, MATTHEW
SCOTT O WEN, J ASON M. WILCOX ; L ESLIE M. SCHMIDT , New
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 2
York, NY; MARK S. WIGLEY , Ward and Smith, PA, Raleigh,
NC.
______________________
Before T ARANTO, HUGHES , and STARK, Circuit Judges.
STARK, Circuit Judge.
Tenaris Coiled Tubes LLC and Tenaris S.A. (collec-
tively, “Tenaris”) appeal the district court’s grant of sum-
mary judgment to Global Tubing LLC (“Global Tubing”).
The district court determined that Tenaris committed in-
equitable conduct in obtaining U.S. Patent Nos. 9,803,256
(“’256 patent”), 10,378,074 (“’074 patent”), and 10,378,075
(“’075 patent”). Global Tubing cross-appeals the district
court’s entry of summary judgment in favor of Tenaris on
Global Tubing’s Walker Process fraud claim, which sought
to hold Tenaris liable for attempted monopolization. We
conclude that genuine disputes of material fact preclude
summary judgment in both instances. Therefore, we va-
cate and remand for further proceedings.
I
A
Coiled tubing is pliable metal pipe spooled around a
large reel. It is used predominantly in the horizontal wells
of the oil and gas industry. In the 1990s, Southwestern
Pipe, Inc. (“Southwestern”) utilized a “quench and temper”
method to treat its piping. This process involved exposing
the metal to extreme heat before quickly cooling (quench-
ing) and then reheating it (tempering). The result was a
coiled tubing product Southwestern called “CYMAX,”
which the company hoped would be stronger and more du-
rable than its jointed or rolled predecessors. Despite its
seemingly superior properties, however, CYMAX was not a
commercial success and Southwestern exited the coiled
tubing market.
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 3
In 2006, Tenaris acquired Southwestern’s assets, in-
cluding the manufacturing furnace Southwestern had used
to produce CYMAX as well as documents describing the
CYMAX production process (the “CYMAX Documents”).
The CYMAX Documents disclose a version of CYMAX,
called “CYMAX 100,” having a chemical composition that
includes 0.13-0.17 wt. % carbon and a yield strength of 100
ksi.1 J.A. 5282.
Several years later, Tenaris created its own coiled tub-
ing product, “BlueCoil,” which shares several characteris-
tics with CYMAX. One commonality is that BlueCoil is
manufactured using a “quench and temper” process. Also,
BlueCoil contains 0.17-0.35 wt. % carbon and has a yield
strength of between 95 and 140 ksi.
1
Tenaris ultimately obtained five patents relating to its
quenched-and-tempered coiled tubing product. The first of
these, the ’256 patent, lists Martín Valdez, Gonzalo Gomez,
Jorge Mitre, and Bruce Reichert as inventors. Claim 1 of
the ’256 patent recites:
A coiled steel tube having improved yield strength
and fatigue life at weld joints of the coiled tube, the
coiled steel tube comprising:
a plurality of strips welded together end to end by
a bias weld and formed into a coiled steel tube, each
of the plurality of strips having base metal regions,
bias weld joints, and heat affected zones surround-
ing the bias weld joints, each of the plurality of
welded strips comprising:
1 “Ksi” refers to kilopounds per square inch and is a
measure of yield strength; i.e., the amount of stress a ma-
terial can withstand without permanent deformation.
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 4
a yield strength greater than about 80 ksi;
a composition comprising iron and:
0.17-0.35 wt. % carbon;
0.30-2.00 wt. % manganese;
0.10-0.30 wt. % silicon;
0.010-0.040 wt. % aluminum;
up to 0.010 wt. % sulfur; and
up to 0.015 wt. % phosphorus; and
wherein the coiled steel tube has a final microstruc-
ture formed from a full body heat treatment ap-
plied to the coiled steel tube;
wherein the final microstructure comprises a mix-
ture of tempered martensite and bainite;
wherein the final microstructure of the coiled steel
tube comprises more than 90 volume % tempered
martensite in the base metal regions, the bias weld
joints, and the heat affected zones;
wherein the final microstructure across all base
metal regions, bias weld joints, and heat affected
zones is homogeneous; and
wherein the final microstructure comprises a uni-
form distribution of fine carbides across the base
metal regions, the bias weld joints, and the heat af-
fected zones.
J.A. 1090 (emphasis added).
The weight percentage range for all but one element of
the chemical composition claimed in the ’256 patent over-
laps with the corresponding ranges disclosed in the
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 5
CYMAX Documents.2 For example, claim 1 requires car-
bon in an amount of 0.17 to 0.35 wt. %, while the carbon
range taught in the CYMAX Documents is 0.13 to 0.17 wt.
%. Thus, claim 1 and the CYMAX Documents overlap at
0.17 wt. %. Similarly, the ’256 patent claims “a yield
strength greater than about 80 ksi,” while the CYMAX Doc-
uments disclose a yield strength of 100 ksi. J.A. 1090,
5282. Thus, both formulations recite a yield strength that
overlaps at 100 ksi and above.
2
Along with the application that ultimately became the
’256 patent, Tenaris submitted 573 prior art references to
the Patent and Trademark Office (“PTO”). Among them
was a 1992 paper presented at the Offshore Technology
Conference by G.B. Chitwood and three coauthors, two of
whom were Southwestern engineers, entitled “High-
Strength Coiled Tubing Expands Service Capabilities”
(“Chitwood”). Chitwood details the manufacturing and
testing processes for CYMAX and discloses coiled tubing
composed of “low-carbon 4100 series steel” having a mini-
mum of “100 ksi yield strength.” J.A. 3462-63. The parties
agree that the tubing Chitwood is referring to is CYMAX
100. Although Chitwood does not expressly disclose speci-
fications for CYMAX 100’s chemical composition, the “low-
carbon 4100 series steel” it teaches undisputedly corre-
sponds to a carbon range of at least 0.18 to 0.43 wt. %. No-
tably, the CYMAX Documents, like the Chitwood
reference, disclose that “[t]he steel sheet shall be 4100 se-
ries,” consistent with the industry standard set by the
2 Although immaterial to this appeal, the 0.025 wt. %
phosphorous specification of the CYMAX Documents is out-
side the range claimed by claim 1 of the ’256 patent, which
is “up to 0.015 wt. % phosphorous.” Compare J.A. 1090
with J.A. 5282.
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 6
American Society for Testing and Materials (“ASTM”) in
specification A-607. J.A. 5282.
During prosecution of the ’256 patent, Tenaris submit-
ted Chitwood to the PTO but did not submit the CYMAX
Documents. In Tenaris’ view, Chitwood discloses materi-
ally the same information as the CYMAX Documents, in-
cluding a carbon range (0.18-0.43 wt. %) that overlaps with
the carbon range claimed in claim 1 of its ’256 patent (0.17-
0.35 wt. %). The specific CYMAX 100 carbon range dis-
closed in the CYMAX Documents, 0.13-0.17 wt. %, which
includes the 0.17 wt. % point of overlap with claim 1’s 0.17-
0.35 wt. % range, is not, however, disclosed in Chitwood.
A patent examiner initially rejected the proposed
claims of the ’256 patent for obviousness, finding that the
prior art taught the same structure and process used by the
patent. The examiner further determined that claimed
properties, such as yield strength, were inherent features
and were not novel.
As part of its attempt to overcome this rejection,
Tenaris filed an inventor declaration from Dr. Martín Val-
dez (the “Valdez Declaration”), which addressed purported
secondary considerations of non-obviousness relating to
claim 1. In the course of preparing the Valdez Declaration,
Tenaris’ prosecution counsel asked Dr. Valdez for evidence
that might be included. In questions embedded in a draft
of the declaration (the “Draft Declaration”), counsel specif-
ically asked Dr. Valdez: “Is there any particular evidence
of long felt need of a particular property of the coiled tube?”
“Can you provide any evidence or details of this long felt
need?” and “Do you have any evidence of people struggling
to achieve the claimed coiled tube?” J.A. 7721 (capitaliza-
tion omitted).
Dr. Valdez responded to counsel with a series of type-
written “comment bubbles” in the margins of a Microsoft
Word version of the Draft Declaration. In these comments,
Dr. Valdez noted that “[t]here was an attempt called
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 7
Cymax” which, like BlueCoil, “produce[d] 100 ksi but the
[carbon] chemistry was C:0.13-0.17[%] (which is outside
our carbon range).” Id. Dr. Valdez’s statement that
CYMAX’s 0.13-0.17 wt. % was “outside” claim 1’s carbon
range, which is 0.17-0.35 wt. %, is mistaken, given that the
ranges share the overlapping point of 0.17 wt. %.
In another part of his margin comments, Dr. Valdez re-
ferred to the CYMAX Documents and indicated he was
providing them to counsel. Dr. Valdez specifically directed
counsel’s attention to “page 30 of the Cymax pdf [in which]
you can see the spec[ification] of the CYmax 100 which was
0.13-0.17 [wt. %] Carbon.” Id.; see also J.A. 5282 (Page 30:
“Specification for CYMAX 100”). Elsewhere in this com-
ment bubble, Dr. Valdez wrote, referring to the CYMAX
Documents: “I am not sure it is a good idea to disclose this
document.” J.A. 7721.
As we have already noted, prosecution counsel did not,
at any point during the prosecution of the ’256 patent, pro-
vide the CYMAX Documents to the examiner. The exam-
iner, after receiving the Valdez Declaration and knowing
nothing of the CYMAX Documents, withdrew the rejection
and allowed the ’256 patent to issue.
3
Tenaris filed additional patent applications, each of
which claimed priority to the ’256 patent. Two “child” pa-
tents are the ’074, a continuation of the ’256 patent, and
the ’075, a divisional of it. The claims of the ’074 and ’075
patents are substantially similar to those of the ’256 pa-
tent, including in their carbon ranges (0.16-0.35 wt. %);
their differences are not material to the issues in this ap-
peal.
These child patents were prosecuted by different attor-
neys at a different law firm than the one responsible for the
prosecution of the ’256 patent. Tenaris provided the
CYMAX Documents to the new firm. In connection with
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 8
the prosecution of the ’074 and ’075 patents, the new attor-
neys informed Tenaris that “the CYMAX Documents come
close to the inventions included in the continuations, and
therefore, we need to disclose them to the patent office.”
J.A. 5542. Counsel added that if the CYMAX Documents
were cited by Global Tubing in a challenge to the validity
of Tenaris’ patents, “Global would likely prevail [and the
PTO] would invalidate the [’074 and ’075] continuations
and even perhaps the ’256 [patent itself].” Id.
Tenaris’ in-house patent counsel initially resisted sub-
mitting the CYMAX Documents to the PTO, suggesting
they did not qualify as prior art because they were never
publicly printed or disclosed. Prosecution counsel never-
theless continued to urge Tenaris to submit them, noting
“[i]t appears from the face of the [D]ocuments that they
have been disclosed [publicly] or were intended for disclo-
sure.” J.A. 5545; see also J.A. 5549 (“[T]he CYMAX refer-
ences bear several ‘earmarks’ of publication.”); J.A. 10131
(“Re-read Rule 56 . . . . Note the absence of any qualifying
language such as ‘. . . but only if you’re absolutely certain
that it qualifies as prior art.’”); J.A. 8416 (“[T]o comply with
[the] duty [of candor] to the USPTO regarding prosecution
of patents, we need [to] at least . . . [i]nterview all 4 inven-
tors to determine if they know anything about whether the
Cymax [D]ocuments were distributed publicly.”).
Ultimately, Tenaris submitted the CYMAX Documents
to the PTO as part of the prosecution of the ’074 and ’075
patents. However, it only did so by splitting apart the
pages of the CYMAX Documents and submitting them as
separate references – and never including pages 27-31
among any of them. This meant that Tenaris did not at the
time disclose to the PTO page 30 of the CYMAX Docu-
ments, which contains CYMAX 100’s chemical composition
and, in particular, the 0.17 wt. % carbon point common to
the claims of Tenaris’ ’256 (0.17-0.35 wt. %), ’074 (0.16-0.35
wt. %), and ’075 (0.16-0.35 wt. %) patents. The PTO issued
the ’074 and ’075 patents.
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 9
4
Tenaris later prosecuted “grandchild” patents of the
’256 patent, including application Nos. 16/538,326 (“’326
application”) and 16/538,407 (“’407 application”). In these
prosecutions, Tenaris finally submitted the entirety of the
CYMAX Documents to the PTO, including page 30.
Tenaris also filed terminal disclaimers, ensuring that the
claims of the patents resulting from the ’326 and ’407 ap-
plications would expire on the same date as the claims of
the ’256 patent. After Tenaris amended these grandchild
claims in ways whose relevance to this appeal is disputed,
the examiner issued notices of allowance for both applica-
tions. See infra Part III.C.2 & n.6.
B
1
Global Tubing manufactures its own quenched-and-
tempered coiled tubing product, “DURACOIL,” which it
launched in 2017, two years after Tenaris entered the mar-
ket with BlueCoil. According to Global Tubing, Tenaris
told customers at a 2017 industry trade show that
DURACOIL was a copy of BlueCoil and intimated that
Tenaris was about to sue Global Tubing for patent infringe-
ment. Rather than await litigation, Global Tubing sued
Tenaris in October 2017, seeking a declaratory judgment
that DURACOIL does not infringe the ’256 patent. Tenaris
counterclaimed, alleging DURACOIL infringes the ’256 pa-
tent as well as the ’074 and ’075 patents.
During discovery, Tenaris inadvertently produced com-
munications that had occurred among its inventors and
prosecution counsel. A magistrate judge rejected Tenaris’
efforts to “claw back” these materials, ordering their pro-
duction under the crime-fraud exception to the attorney-
client privilege. In particular, the judge found that Dr. Val-
dez’s statement in the margin of the Draft Declaration – “I
am not sure it is a good idea to disclose this document” –
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 10
was “a rare example of direct evidence of an intent to de-
fraud.” J.A. 4044. The magistrate judge further found, al-
beit in the context of a discovery dispute, that fraudulent
intent was the single most reasonable inference to be
drawn from this evidence.
Thereafter, Global Tubing amended its complaint to
add the two claims at issue in this appeal: (1) inequitable
conduct; and (2) Walker Process fraud, i.e., that Tenaris
was attempting to use its fraudulently obtained patents to
monopolize the market. See Walker Process Equip., Inc. v.
Food Mach. & Chem. Corp., 382 U.S. 172, 177 (1965). The
inequitable conduct claim was based on Tenaris’ nondisclo-
sure to the PTO of the CYMAX Documents, which Global
Tubing alleged were material to patentability and were
withheld from the PTO with the intent to defraud. The
Walker Process fraud claim alleged that Tenaris misused
its “significant market share and very broad patents” to
create a “dangerous probability” that Tenaris would
achieve a monopoly. J.A. 2059.
As part of discovery, Global Tubing deposed Dr. Valdez.
During the deposition, Global Tubing’s counsel asked Dr.
Valdez what he had meant when he wrote to prosecution
counsel he was “not sure it is a good idea” to disclose the
CYMAX Documents to the PTO. J.A. 7799. Dr. Valdez re-
plied that he brought up CYMAX in response to the attor-
ney’s question about secondary considerations of non-
obviousness, because “the only reference that comes to my
mind of someone struggling to try to produce what we were
trying to do was CYMAX.” J.A. 7798 (“What trigger[ed] me
to talk about CYMAX [with our lawyer] was [Southwest-
ern’s] struggl[e] of producing quench and temper coiled
tubing. I have this idea that [CYMAX] was not a successful
product . . . [because it] died in the Nineties as it was trying
to be born.”); J.A. 7799 (“When [our lawyer] asked about
evidence of people struggling to achieve the claimed coiled
tubing, [what] would come to my mind is CYMAX.”).
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 11
Nonetheless, in Dr. Valdez’s view, CYMAX had “a dif-
ferent range of properties” than those of Tenaris’ BlueCoil
embodiment of the ’256 patent’s claims. J.A. 7799. “It’s a
different chemical composition,” he insisted. Id. He ex-
plained that in the “comment bubble” on the Draft Decla-
ration, he had “pointed to a difference that [CYMAX] has,
for example, the [lower] carbon [percentage].” J.A. 7798;
see also J.A. 7797 (“[W]e focused all of our development o[n]
our higher carbon steel . . . it’s an important part of the
[BlueCoil] product.”). According to Dr. Valdez, this differ-
ence led him to believe that “maybe [CYMAX] [i]s not use-
ful” to prosecution. J.A. 7799 (“I had the idea it wasn’t.”).
Ultimately, Dr. Valdez concluded that CYMAX “was a dif-
ferent product from the one we were claiming. So I thought
it was not a good idea” to disclose it, since “it will be con-
fusing.” Id. (“I thought maybe it was not a good idea since
it will not be aligned with the claimed coiled tubing.”).
Still, Dr. Valdez continued, “I thought I’m not sure, so I left
it also to [counsel] for his opinion,” which was “the reason
why I include[d]” the CYMAX Documents in what he pro-
duced to the attorney, “for him to have a look at the docu-
ment[s].” Id.
Dr. Valdez testified to an additional reason he was un-
sure whether the CYMAX Documents needed to be submit-
ted to the PTO. He thought the substantive content of the
CYMAX Documents had already been disclosed via Chit-
wood, because in his view “Chitwood discloses CYMAX,”
and “we disclosed Chitwood as representative of CYMAX.”
J.A. 7793 (“Chitwood was CYMAX to me.”). He elaborated:
Chitwood was the public record of what CYMAX
did. I mean, it was equivalent in content . . . . The
Chitwood paper describes a problem solve which is
the same as CYMAX, which was the need to in-
crease yield strength. [Chitwood] disclose[d] the
coiled tubing that is heat treated, CYMAX did [too].
[Chitwood] includes a reference to the chemistries
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 12
which [also in] CYMAX are included. Actually
Chitwood is broader than CYMAX.
Id.; see also J.A. 7794 (“They were equivalent for the pur-
pose of letting the examiner know that there has been a
prior attempt to heat treat coiled tubing, who did it, in
which company, which steels to obtain which microstruc-
ture. That was CYMAX and that was Chitwood.”).
2
Following the completion of discovery, the parties filed
cross-motions for summary judgment. Global Tubing
sought summary judgment on its inequitable conduct
claim, while Tenaris sought summary judgment of no lia-
bility on both Global Tubing’s inequitable conduct and
Walker Process claims. The district court granted sum-
mary judgment of inequitable conduct to Global Tubing
and granted summary judgment of no liability for Walker
Process fraud to Tenaris.
With respect to inequitable conduct, the district court
concluded there was clear and convincing evidence that Dr.
Valdez, on behalf of Tenaris, intended to deceive the PTO
by withholding the CYMAX Documents, which the court
further determined were material to patentability and not
cumulative of Chitwood. The court further reasoned that
the inequitable conduct plaguing the ’256 parent patent
also infected the ’074 and ’075 child patents, given that
Tenaris failed to disclose page 30 (and several other pages)
of the CYMAX Documents even in those latter prosecu-
tions.
With respect to Global Tubing’s Walker Process fraud
claim, the court granted summary judgment to Tenaris.
The court determined that, because Tenaris was “such a
small market player,” Global Tubing could not prove
Tenaris had market power sufficient to pose a dangerous
probability of achieving a monopoly, an essential element
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 13
of Global Tubing’s claim. J.A. 31191. This failing was, in
the court’s view, dispositive.
Tenaris now appeals the judgment of inequitable con-
duct and Global Tubing cross-appeals the judgment of no
Walker Process fraud. The district court had jurisdiction
under 15 U.S.C. § 4 and 28 U.S.C. §§ 1331, 1338(a), &
2201. We have jurisdiction under 28 U.S.C. § 1295(a)(1).
II
We apply regional circuit law to determine the stand-
ards for obtaining summary judgment. See United Servs.
Auto. Ass’n v. PNC Bank N.A., 139 F.4th 1332, 1336 (Fed.
Cir. 2025); Ericsson Inc. v. TCL Commc’n Tech. Holdings
Ltd., 955 F.3d 1317, 1324 (Fed. Cir. 2020). Summary judg-
ment is appropriate only “if the movant shows that there is
no genuine dispute as to any material fact and the movant
is entitled to judgment as a matter of law.” Fed. R. Civ. P.
56(a). “A genuine dispute of material fact exists if the evi-
dence is sufficient for a reasonable jury to return a verdict
for the nonmoving party.” Fleming v. Bayou Steel BD
Holdings II LLC, 83 F.4th 278, 293 (5th Cir. 2023) (internal
quotation marks omitted).
The party moving for summary judgment bears the
burden of demonstrating the absence of any genuine issue
of material fact. See Celotex Corp. v. Catrett, 477 U.S. 317,
323 (1986). In opposing such a motion, the nonmoving
party must “set forth specific facts showing that there is a
genuine issue for trial.” Anderson v. Liberty Lobby, Inc.,
477 U.S. 242, 248 (1986) (internal quotation marks omit-
ted). A nonmoving party may support its position by “citing
to particular parts of materials in the record, including
depositions, documents, electronically stored information,
affidavits or declarations,” or by “showing that the materi-
als cited [by the moving party] do not establish the absence
. . . of a genuine dispute.” Fed. R. Civ. P. 56(c)(1). In eval-
uating a motion for summary judgment, all reasonable
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 14
inferences must be drawn in the nonmovant’s favor. See
Anderson, 477 U.S. at 255.
Inequitable conduct is an issue of patent law that must
be proven according to standards set out in our own prece-
dent. See Duro-Last, Inc. v. Custom Seal, Inc., 321 F.3d
1098, 1106 (Fed. Cir. 2003). “We review the district court’s
decision to grant summary judgment for inequitable con-
duct de novo.” Leviton Mfg. Co. v. Universal Sec. Instru-
ments, Inc., 606 F.3d 1353, 1358 (Fed. Cir. 2010).
We similarly “apply Federal Circuit law, rather than
regional law, to a Walker Process claim.” Chandler v. Phoe-
nix Servs. LLC, 1 F.4th 1013, 1017 (Fed. Cir. 2021) (inter-
nal quotation marks omitted). We review summary
judgment determinations concerning a Walker Process
fraud claim de novo. See In re Indep. Serv. Orgs. Antitrust
Litig., 203 F.3d 1322, 1324-25 (Fed. Cir. 2000).
III
Tenaris appeals the district court’s grant of summary
judgment on Global Tubing’s inequitable conduct claim.
Tenaris contends the district court committed reversible
error in two respects. First, Tenaris argues that it demon-
strated a genuine dispute of material fact as to whether Dr.
Valdez acted with the specific intent to defraud the PTO.
Second, Tenaris contends that the record reveals an addi-
tional genuine dispute as to whether the withheld CYMAX
Documents are material to the patentability of the ’256,
’074, and ’075 patents, or are instead merely cumulative of
the Chitwood reference that was submitted in those prose-
cutions. We address both grounds in turn.
A
To prevail on an inequitable conduct claim, a party
must prove at least one specified individual acted with “the
specific intent to deceive the PTO” by withholding material
information. Luv n’ Care, Ltd. v. Laurain, 98 F.4th 1081,
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 15
1096-97 (Fed. Cir. 2024); see also Exergen Corp. v. Wal-
Mart Stores, Inc., 575 F.3d 1312, 1328-29 (Fed. Cir. 2009).
With respect to intent to deceive, “gross negligence or
negligence under a ‘should have known’ standard” is insuf-
ficient; instead, actual deceptive intent must be shown to
be “the single most reasonable inference able to be drawn
from the evidence.” Therasense, Inc. v. Becton, Dickinson
& Co., 649 F.3d 1276, 1290 (Fed. Cir. 2011) (en banc) (in-
ternal quotation marks omitted). Specifically, “the accused
infringer must prove by clear and convincing evidence that
the applicant knew of the [withheld] reference, knew that
it was material, and made a deliberate decision to withhold
it.” Id.
For a prior art reference to be material, it must be
shown by a preponderance of the evidence that, but-for the
reference having been withheld, the patent would not have
been granted. See Belcher Pharms., LLC v. Hospira, Inc.,
11 F.4th 1345, 1352 (Fed. Cir. 2021). “Prior art is but-for
material if the PTO would have denied a claim had it
known of the undisclosed prior art,” but it “is not but-for
material if it is merely cumulative.” Cal. Inst. of Tech. v.
Broadcom Ltd., 25 F.4th 976, 991 (Fed. Cir. 2022) (internal
citation omitted). “A reference is cumulative when it
teaches no more than what a reasonable examiner would
consider to be taught by the prior art already before the
PTO.” Regeneron Pharms., Inc. v. Merus N.V., 864 F.3d
1343, 1350 (Fed. Cir. 2017) (internal quotation marks omit-
ted).
B
We begin with intent to defraud. The district court de-
termined that Dr. Valdez’s statement in the comment bub-
ble on the Draft Declaration, “‘I am not sure it is a good
idea to disclose this document,’” proved intent. J.A. 14
(quoting J.A. 7721). The court held “there is no other rea-
sonable inference that can be drawn from Tenaris’ with-
holding the CYMAX [D]ocument[s] from the Patent Office,
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 16
other than intent to deceive.” Id. The court recognized, but
rejected, Tenaris’ argument that Dr. Valdez’s statement
should be read as expressing doubt about the relevance of
the CYMAX Documents, given his purported (mistaken)
belief that the carbon ranges did not overlap. To the dis-
trict court, this interpretation of the evidence “does not pre-
sent an equally reasonable inference to Global’s intent to
deceive argument.” Id.
In our view, the district court erred because it failed to
consider the evidence of Dr. Valdez’s intent in the light
most favorable to Tenaris, the nonmoving party. The court
neglected to draw all reasonable inferences from the record
in favor of Tenaris. Doing so now, we conclude there is a
genuine dispute as to the material fact of whether the sin-
gle most reasonable inference is that Dr. Valdez acted with
the specific intent to defraud the PTO. Summary judgment
of inequitable conduct was, therefore, improper.
1
The attorneys prosecuting Tenaris’ ’256 patent appli-
cation sent Dr. Valdez the Draft Declaration, which in-
cluded numerous questions to Dr. Valdez, including: “Do
you have any evidence of people struggling to achieve the
claimed coiled tube?” J.A. 7721. In doing so, the attorneys
were soliciting from Dr. Valdez evidence of secondary con-
siderations of non-obviousness that they could include as
part of Tenaris’ response to an office action rejection. See
id. (“Is there any particular evidence of long felt need?”).
Dr. Valdez replied to prosecution counsel by marking up
the Draft Declaration and including a “comment bubble”
along the margin that read, in full:
The claimed coiled tubing on the range of proper-
ties we are claiming ([e]specially the one we are
selling 110-125-140 ksi) was not explore[d] before[.]
There was an attempt called Cymax (I include a pa-
per/document for your reference)[.] The intention
was to go higher than 70 ksi, they produce[d] 100
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 17
ksi but the chemistry was C:0[.]13-0[.]17 (which is
outside our carbon range)[.] In page 30 of the Cy-
max pdf doc you can see the spec of the CYmax 100
which was 0[.]13-0[.]17 Carbon[.] I am not sure it
is a good idea to disclose this document.
Id. (bracketed material added).
From this evidence, Global Tubing argues that the fi-
nal part of Dr. Valdez’s comment – “I am not sure it is a
good idea to disclose this document” – is as close to an ad-
mission of fraudulent intent as one ever sees in patent liti-
gation. This is how the district court viewed the remark,
opining: “Rarely do courts come across such stark evidence
of the intent fork of inequitable conduct.” J.A. 14; see also
J.A. 4044 (“This statement, questioning whether it is a
good idea to disclose the CYMAX material, is a rare exam-
ple of direct evidence of an intent to defraud.”). And surely,
at trial, a factfinder could reasonably find that Dr. Valdez
was thinking that the CYMAX Documents disclose the
0.13-0.17 wt. % carbon range, which overlaps with the 0.17-
0.35 wt. % carbon range of the proposed claims, leading
him to fear that submitting the Documents would cause the
claims to be finally rejected as obvious based on the over-
lapping 0.17 wt. % carbon point.
Alternatively, however, and crucial at the summary
judgment stage, a reasonable factfinder, taking the evi-
dence in the light most favorable to Tenaris, could instead
credit Dr. Valdez’s testimony. Dr. Valdez explained in his
deposition that he believed the CYMAX Documents dis-
closed a “lower carbon” steel tubing range of 0.10 to 0.17
wt. %. J.A. 7797 (“So lower carbon, we are referring to the
conventional coiled tubings which are between 0.1 to 0.16,
17 percent.”). By contrast, he continued, the ’256 patent
“claimed coiled tubing included a chemistry with higher
carbon. So the chemistry with the lower carbon” disclosed
in the CYMAX Documents “was outside of the carbon range
of the claimed coiled tubing.” J.A. 7798 (“I pointed to a
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 18
difference that it has, for example, [with] the carbon.”); J.A.
7799 (“[CYMAX] was a different range of properties than
[BlueCoil].”). On this point, Dr. Valdez was wrong, both as
a matter of fact and a matter of patent law. The CYMAX
Documents disclose a carbon range that overlaps at its end
point, 0.17 wt. %, with the lower bound of the claimed
range of the ’256 patent. See In re Geisler, 116 F.3d 1465,
1469 (Fed. Cir. 1997) (“[A] claimed invention [may be] ren-
dered prima facie obvious by the teachings of a prior art
reference that discloses a range that touches the range re-
cited in the claim.”).
So Dr. Valdez was mistaken, in his deposition testi-
mony and also in his comment in the margin of the Draft
Declaration, when he said the carbon ranges of the ’256 pa-
tent claims and CYMAX Documents do not overlap. What
could Dr. Valdez’s faulty insistence on this point tell a rea-
sonable factfinder? It could mean he fabricated his view
that there is no overlap; surely he knows 0.17 overlaps with
0.17, and his refusal to acknowledge that undeniable real-
ity may mean he lacks credibility and his testimony should
be rejected. On the other hand, it may mean Dr. Valdez
was genuinely confused about what the CYMAX Docu-
ments show and whether they are relevant to proving that
others tried but failed to invent what the ’256 patent
claims.
As between competing reasonable inferences that may
be drawn from the same evidence, courts are bound at sum-
mary judgment to accept those inferences that are most fa-
vorable to the nonmoving party. Thus, here, we must
credit the reasonable inference that Dr. Valdez was inno-
cently mistaken about the lack of overlap in the carbon con-
tent and the legal import of that overlap. At this stage and
on this evidence, we may not conclude that Dr. Valdez was
instead lying at his deposition and intended to deceive the
PTO.
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 19
2
Dr. Valdez further explained that he thought the
CYMAX Documents showed others trying to achieve some-
thing different than the ’256 patent’s high carbon mixture:
a low carbon formulation. J.A. 7799 (“It’s a different chem-
ical composition. So maybe it’s not useful.”). His concern,
he insisted, was that the failure depicted in the CYMAX
Documents might not be responsive to prosecution coun-
sel’s inquiry to him. Id. (“I thought maybe it was not a good
idea since it will not be aligned with the claimed coiled tub-
ing. . . . So it will be confusing.”). Counsel had told Dr.
Valdez, “we need to make sure the evidence in our declara-
tion is tied directly into our claims.” J.A. 7710. Dr. Valdez
testified that this instruction made him uncertain whether
the CYMAX Documents met this seemingly exacting stand-
ard. J.A. 7798-99.
Of course, it is possible that Dr. Valdez only said these
things as post-hoc rationalizations, because he in fact
feared the overlapping carbon range would confirm, rather
than disrupt, the obviousness rejection of the ’256 patent
claims. But viewing the evidence in the light most favora-
ble to Tenaris requires that we credit, for the purposes of
evaluating Global Tubing’s summary judgment motion, the
reasonable inference that Dr. Valdez thought the CYMAX
Documents lacked relevance because they involved a dif-
ferent carbon range. See Dig. Control, Inc. v. Charles
Mach. Works, 437 F.3d 1309, 1314 (Fed. Cir. 2006) (“[W]e
have refused summary judgment where the plaintiff sub-
mitted an affidavit that set forth a non-frivolous explana-
tion that could lead a finder of fact to determine that his
declaration to the PTO was not false or misleading, or
where the plaintiff stated facts supporting a plausible jus-
tification or excuse for the misrepresentation.”) (internal
citations, alterations, and quotation marks omitted).
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 20
3
Dr. Valdez further claimed to have believed that “Chit-
wood discloses CYMAX,” and because Tenaris had already
“disclosed Chitwood as representative of CYMAX,” he
thought there was no reason to also submit the CYMAX
Documents. J.A. 7793. He insisted that, as far as he un-
derstood, “Chitwood was the public record of what CYMAX
did. . . . [I]t was equivalent in content . . . [because] [t]he
Chitwood paper describes a problem solve which is the
same as CYMAX, which was the need to increase yield
strength.” Id.; see also J.A. 7794 (“They were equivalent
for the purpose of letting the examiner know that there has
been a prior attempt to heat treat coiled tubing, who did it,
in which company, which steels to obtain which microstruc-
ture. That was CYMAX and that was Chitwood.”). Be-
cause a reasonable factfinder could credit this testimony,
at summary judgment we must infer that Dr. Valdez’s rea-
sons for not producing the CYMAX Documents included his
belief that they were cumulative and he was not, to the con-
trary, withholding them for the purpose of deceiving the
PTO.3
Notwithstanding his doubts, Dr. Valdez provided the
CYMAX Documents to prosecution counsel. If Dr. Valdez
intended to defraud the PTO, the most likely way to ensure
the examiner would never see the CYMAX Documents
would have been to omit mention of them altogether, in-
cluding to Tenaris’ own attorneys. Instead, he produced
them to counsel and drew attention to them with his bubble
comment. See J.A. 7721 (“There was an attempt called Cy-
max (I include a paper/document for your reference).”).
That enabled counsel to make the decision about what
3 As we explain below, there is a genuine dispute of
material fact as to whether the CYMAX Documents are cu-
mulative of Chitwood. See infra, Part III.C.
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 21
needed to be disclosed to the PTO. See J.A. 7799 (“I left it
also to [him] for his opinion.”).
In sum, a reasonable factfinder could credit Dr. Val-
dez’s testimony that he was genuinely unsure as to
whether the CYMAX Documents were relevant to the pros-
ecution of the ’256 patent. Tenaris has therefore met its
burden to identify record evidence showing that Dr. Val-
dez’s intent is a genuinely disputed fact. See Paragon Po-
diatry Lab., Inc. v. KLM Labs., Inc., 984 F.2d 1182, 1190
(Fed. Cir. 1993) (“If the facts of materiality or intent are
reasonably disputed, the issue is not amenable to summary
judgment.”) (internal quotation marks and emphasis omit-
ted); see also Fed. R. Civ. P. 56(c)(1)(A) (“A party asserting
that a fact . . . is genuinely disputed must support the as-
sertion by citing to . . . depositions, documents, . . . affida-
vits or declarations.”) (subsection partition omitted).
Hence, summary judgment was not appropriate.
4
Notwithstanding the above analysis, Global Tubing ar-
gues that the district court was permitted to resolve for it-
self, by application of a “rare” Fifth Circuit exception to the
ordinary Rule 56 standard, that Dr. Valdez intended to de-
ceive the PTO. Nunez v. Superior Oil Co., 572 F.2d 1119,
1124 (5th Cir. 1978). In the Fifth Circuit, “at the summary
judgment stage a judge in a bench trial has the limited dis-
cretion to decide that the same evidence, presented to him
or her as trier of fact in a plenary trial, could not possibly
lead to a different result.” In re Placid Oil Co., 932 F.2d
394, 398 (5th Cir. 1991); see also Champagne v. A & T Mar.
Logistics Inc., 127 F.4th 620, 625 (5th Cir. 2025) (“[I]n
bench-trial cases the district court has greater discretion to
grant summary judgment.”) (internal quotation marks
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 22
omitted).4 Even in the Fifth Circuit, however, this “en-
hanced leeway,” Fleming, 83 F.4th at 294, which may in-
clude drawing inferences in favor of the moving party,
exists “only when the evidentiary facts are not disputed
and there are no issues of witness credibility,” Manson
Gulf, LLC v. Mod. Am. Recycling Serv., Inc., 878 F.3d 130,
134 (5th Cir. 2017) (internal quotation marks omitted); see
also Nunez, 572 F.2d at 1123-24. The Fifth Circuit “for-
bid[s] the judge from drawing inferences from the evidence
submitted on summary judgment . . . [when] those infer-
ences involve issues of witness credibility or disputed ma-
terial facts.” Placid Oil, 932 F.2d at 398; see also Manson
Gulf, 878 F.3d at 136 (“By adopting one side of [the wit-
ness’] story as ‘[t]he most convincing evidence’ while ne-
glecting [his own] contrary account, the court, in essence,
found one version more credible than the other. And Nunez
forbids credibility determinations on a cold summary-judg-
ment record.”).
4 Global Tubing’s argument is premised on inequitable
conduct being tried to a judge, not a jury, which is normally
the case. See, e.g., Agfa Corp. v. Creo Prods. Inc., 451 F.3d
1366, 1371 (Fed. Cir. 2006). Here, however, the parties
have contemplated that if both inequitable conduct and
Walker Process fraud have to be tried – which our disposi-
tion of this appeal may require – portions of that trial will
be to a jury, including with respect to issues of intent. See
id. at 1372 (“[A] trial judge could not conduct a bench trial
(and preclude a jury trial) on equitable declaratory relief
claims where that trial would resolve ‘common’ issues with
a claim subject to jury resolution.”); see also Beacon Thea-
tres, Inc. v. Westover, 359 U.S. 500, 503-04 (1959). It may
be, then, that the Fifth Circuit’s exception to Rule 56 is in-
applicable for the further reason that at least some aspects
of inequitable conduct will not be the subject of a bench
trial in this case.
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 23
The circumstances here, then, do not come within the
Fifth Circuit’s “rare” exception. Determining whether Dr.
Valdez, when he wrote his comment on the Draft Declara-
tion, was acting with the specific intent to deceive the PTO
– or was instead mistaken about the carbon content range
disclosed in the CYMAX Documents, confused about the
patent law doctrine of secondary considerations of non-ob-
viousness, and of the (reasonable) belief that the CYMAX
Documents were merely cumulative of the already-dis-
closed Chitwood reference – is a highly disputed, material
matter whose resolution turns on the factfinder’s assess-
ment of Dr. Valdez’s credibility. Because the evidentiary
facts are disputed and there are issues of witness credibil-
ity, the district court here could not invoke the “enhanced
leeway” that is sometimes permitted at summary judgment
in non-jury cases under Fifth Circuit law.
Global Tubing additionally suggests that our own
caselaw permits a district court reviewing a motion for
summary judgment of inequitable conduct to draw infer-
ences against the nonmoving party, as the district court did
here. This is incorrect. The cases on which Global Tubing
relies, all of which were issued prior to our decision in The-
rasense (and, hence, under an outdated legal standard), do
not support Global Tubing’s position. See Ferring B.V. v.
Barr Labs., Inc., 437 F.3d 1181, 1192 n.13 (Fed. Cir. 2006)
(“Credibility . . . become[s] an issue once a party offers a
declarant’s testimony in support or in opposition to sum-
mary judgment.”); Paragon, 984 F.2d at 1190 (“If the facts
of materiality or intent are reasonably disputed, the issue
is not amenable to summary judgment.”) (internal quota-
tion marks omitted); Cargill, Inc. v. Canbra Foods, Ltd.,
476 F.3d 1359, 1367 (Fed. Cir. 2007) (applying now-inap-
plicable pre-Therasense standard for materiality of
whether applicant “should have known” examiner would
find reference pertinent to patentability).
Contrary to Global Tubing’s suggestion, “our precedent
urges caution in the grant of summary judgment
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 24
respecting a defense of inequitable conduct.” Paragon, 984
F.2d at 1190. “[A] grant of summary judgment on the issue
of inequitable conduct is permissible, but uncommon. Gen-
erally, the concerns attendant to awards of summary judg-
ment on inequitable conduct relate to the inherently
factual nature of the issue of intent.” Dig. Control, 437
F.3d at 1317; see also Poller v. Columbia Broad. Sys., Inc.,
368 U.S. 464, 473 (1962) (“[S]ummary procedures should
be used sparingly in complex [] litigation where motive and
intent play leading roles.”). These general observations
confirm our conclusion that summary judgment of inequi-
table conduct was not warranted in the specific circum-
stances of this case.5
C
1
Whether the CYMAX Documents are material to pa-
tentability, or are instead cumulative of the Chitwood ref-
erence, presents another genuine dispute of material fact
and, hence, another reason summary judgment should not
have been granted on Global Tubing’s inequitable conduct
claim.
Materiality is a question of fact. See Belcher Pharms.,
11 F.4th at 1352. “[T]he scope and content of prior art and
what the prior art teaches are questions of fact.” Dig. Con-
trol, 437 F.3d at 1319. “Prior art is but-for material if the
5 Because the district court granted summary judg-
ment that inequitable conduct was committed by Dr. Val-
dez, it did not reach Global Tubing’s claims that other
individuals also committed inequitable conduct; nor did it
reach Tenaris’ denials of these claims. See generally Ex-
ergen, 575 F.3d at 1328-29 (holding that inequitable con-
duct claim must identify “a specific individual” who
purportedly committed it). These matters may need to be
resolved on remand.
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 25
PTO would have denied a claim had it known of the undis-
closed prior art. Prior art is not but-for material if it is
merely cumulative.” Broadcom, 25 F.4th at 991 (internal
citation omitted).
It is Global Tubing’s burden to prove, by a preponder-
ance of the evidence, that the withheld CYMAX Documents
are but-for material to patentability. See Regeneron, 864
F.3d at 1350. To prevail on its motion for summary judg-
ment, then, Global Tubing needed to show that a reasona-
ble factfinder, viewing the evidence in the light most
favorable to Tenaris, could only have found that Global
Tubing met this burden. The record does not permit this
conclusion.
A reasonable factfinder could find that Chitwood,
which Tenaris provided to the examiner, discloses a “low-
carbon” steel with a specific chemistry overlapping what
was taught by the undisclosed CYMAX Documents. J.A.
3462-63. Chitwood expressly states that “[t]he material
chosen, a low-carbon 4100 series steel, has sufficient har-
denability to achieve the uniform, martensitic microstruc-
ture from heat treatment,” and it specifically discloses a
yield strength of 100 ksi. J.A. 3463; see also J.A. 11691,
11694. While the district court correctly noted that
“Tenaris fails to identify any part of the Chitwood [article]
that includes the precise chemical specification that the
CYMAX brochure included at page 30,” Tenaris produced
evidence showing that a skilled artisan could have dis-
cerned that specific chemistry from Chitwood and publicly
available sources. J.A. 13. Dr. Valdez spoke to this point
in his deposition, testifying that “Chitwood states the type
of steel you use,” i.e., “low-carbon 4100 series steel.” J.A.
7793; see also J.A. 3463. He continued: “It makes reference
to the ASTM, American Society for Testing and Material[s]
A606 and also for the type of steel used, which are publicly
available to come from a chemical composition.” Id.; see
also J.A. 6978 (“[I]f you look up 4100 series there is a list
of chemistries and the ranges to be included in the ASTM
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 26
4100 series.”). From this information, a person of ordinary
skill in the art would, Dr. Valdez explained, know she could
reference a published trade table of “low-carbon 4100 series
steel,” and thereby discern that the steel used in Chitwood
contains percentage weight components that match those
disclosed at page 30 of the CYMAX Documents.
To be sure, a reasonable factfinder could well reject this
chain of inferences. But they are not unreasonable, and at
summary judgment we must draw all reasonable infer-
ences in the nonmovant’s favor. A reasonable factfinder
could credit Dr. Valdez’s explanation, and doing so would
lead to the conclusion that the CYMAX Documents are cu-
mulative of Chitwood and, therefore, not but-for material.
Summary judgment of materiality is, accordingly, unwar-
ranted.
2
The record contains additional evidence that could sup-
port a finding that the claims of ’256 patent, as well as the
claims of the ’074 and ’075 patents, would have been
granted even had Tenaris disclosed the entirety of the
CYMAX Documents during prosecution. Specifically, dur-
ing the prosecution of the grandchild ’326 and ’407 applica-
tions, Tenaris submitted the entirety of the CYMAX
Documents in exactly the form in which they originally ex-
isted (i.e., not divided, or with page 30 missing, as occurred
in the ’074 and ’075 prosecutions), and the PTO still
granted the claims in those applications.
From this evidence, a reasonable factfinder could find
that the PTO would have granted the ’256, ’074, and ’075
patents, even had the examiner been aware of the CYMAX
Documents, because the closely related grandchild patents
were granted in substantially similar circumstances. To
support the reasonableness of such inferences, Tenaris pro-
duced an expert report from former Commissioner of Pa-
tents Robert L. Stoll, who opined that the grandchild
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 27
prosecutions are “strong evidence that CYMAX is not but-
for material to the ’256, ’074, or ’075 Patents.” J.A. 5104.6
Alternative inferences would also be reasonable. As
Global Tubing emphasizes, the claims of the grandchild pa-
tents were initially rejected and were granted only after
they were amended. Global Tubing insists that these
amendments, which add unrelated limitations (such as an
austenitization cycle performed at 900 degrees Celsius or
higher), were necessary to the patentability of the grand-
child claims, and because those limitations are missing
from the claims of the ’256, ’074, and ’075 patents, these
latter claims never would have issued if the examiner had
the CYMAX Documents. This view of the record may well
be credited at trial. But at the summary judgment stage,
we are obligated to credit the contrary reasonable view of-
fered by Tenaris, as the nonmoving party.
3
Dr. Valdez testified that he believed Chitwood included
all of the relevant information contained in the CYMAX
Documents. He further explained that, in his view,
6 A magistrate judge recommended that the Stoll re-
port be excluded, largely based on the view that “the
Grandchildren patents are not at issue in this case” and are
not “relevant to the issues in this dispute.” J.A. 19. The
district court did not rule on Tenaris’ objection to this rec-
ommendation or otherwise weigh in on the magistrate
judge’s relevance observation, as it was unnecessary to do
so given its other conclusions. On appeal, we treat the Stoll
report as part of the summary judgment record, as counsel
for Global Tubing agreed we should. See Oral Arg. at
42:40-43:37, available at
https://www.cafc.uscourts.gov/oral-arguments/23-1882_06
062025.mp3. We express no view on the merits of Global
Tubing’s motion to exclude the report.
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 28
Chitwood disclosed a broader chemistry than the CYMAX
Documents and Chitwood’s range came closer than
CYMAX’s to the specific chemistry of the ’256 patent
claims. While there is certainly record evidence that can
reasonably be viewed as undermining Dr. Valdez’s testi-
mony,7 at the summary judgment stage the record here re-
veals a genuine dispute of material fact on this issue.
For this reason, as well, the district court should not
have granted summary judgment of inequitable conduct.
We vacate that judgment and remand for further proceed-
ings.8
7 For instance, the record includes an email to Dr. Val-
dez from Dr. Bruce Reichert, a co-inventor of the ’256 pa-
tent, stating that “the chemistries (page 30 for instance for
CYMAX 100) . . . is essentially our chemistry for HS90 [i.e.,
the ’256 patent]. I would not think there is enough carbon
to be hardenable.” J.A. 7656. Dr. Valdez replied, “I have
the same observation.” Id. At trial, the factfinder might
conclude that Valdez’s response indicates that he knew the
CYMAX Documents disclosed the chemistry of the ’256 pa-
tents. Alternatively, however, a reasonable interpretation
of this same passage could be that Dr. Valdez was merely
agreeing that the CYMAX formulation lacked sufficient
carbon by weight to achieve the desired tensile strength.
8 Global Tubing also alleges inequitable conduct based
on affirmative “egregious misconduct,” which is conduct so
severe it excuses the claimant from showing materiality of
a withheld reference (although the claimant must prove
that what was submitted to the PTO was “unmistakably
false”). Apotex Inc. v. UCB, Inc., 763 F.3d 1354, 1362 (Fed.
Cir. 2014) (“[E]gregious misconduct [is] such that materi-
ality could have been presumed.”); see also Therasense, 649
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 29
IV
We turn next to Global Tubing’s cross-appeal, which
seeks to vacate the district court’s grant of summary judg-
ment to Tenaris on Global Tubing’s Walker Process fraud
claim. That claim accuses Tenaris of unlawfully attempt-
ing to monopolize the coiled tubing market through the
fraudulent assertion of the ’256, ’074, and ’075 patents.
Here, again, we conclude that genuine disputes of material
fact preclude summary judgment. Thus, we vacate the
trial court’s judgment.
A
“To succeed on a Walker Process claim, a plaintiff must
prove (1) that the antitrust-defendant obtained the patent
by knowing and willful fraud on the patent office and main-
tained and enforced that patent with knowledge of the
fraudulent procurement, and (2) that the plaintiff can sat-
isfy all other elements necessary to establish a Sherman
Act monopolization claim.” Chandler, 1 F.4th at 1014 (in-
ternal quotation marks omitted).
As to the first prong, “the showing required for proving
inequitable conduct and the showing required for proving
the fraud component of Walker Process liability may be
nearly identical.” TransWeb, LLC v. 3M Innovative Props.
Co., 812 F.3d 1295, 1307 (Fed. Cir. 2016). Here, although
we have vacated the judgment of inequitable conduct, the
record evidence could support a finding that Dr. Valdez
withheld a material prior art reference from the PTO and
did so with the intent to deceive that office. Global Tubing
has demonstrated that a genuine dispute of material fact
F.3d at 1292. For the reasons we explained in connection
with the specific intent element of Global Tubing’s inequi-
table conduct claim, whether the Valdez Declaration is “un-
mistakably false” presents a genuine dispute of material
fact not amenable to resolution at summary judgment.
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 30
exists with respect to the first prong of its Walker Process
fraud claim.
With respect to the second prong, the elements neces-
sary to prove an attempted monopolization claim under § 2
of the Sherman Act are “(1) that the defendant has engaged
in predatory or anticompetitive conduct with (2) a specific
intent to monopolize and (3) a dangerous probability of
achieving monopoly power.” Spectrum Sports, Inc. v.
McQuillan, 506 U.S. 447, 456 (1993). The genuine disputes
of material fact we outline below render summary judg-
ment for Tenaris of no Walker Process fraud improper.
B
At the conclusion of oral argument on the Walker Pro-
cess cross-motions, the district court announced its decision
granting summary judgment to Tenaris, stating:
I’m going to have to grant the motion for summary
judgment. I think that it would be legal error to
hold that such a small market player [Tenaris] was
engaged in attempted monopolization. I think the
acts alleged as constituting an attempt at monopo-
lization are insufficient to create a genuine issue of
material fact.
J.A. 31191; see also J.A. 31151 (“I’m still troubled by the
notion that a patent which gave rise to a suggestion of mar-
ket domination would be a threat of monopoly power when
the market player who had the patent was such a small
percentage of the market.”).
“As a threshold issue in any monopolization claim, the
court must identify the relevant market.” IGT v. All. Gam-
ing Corp., 702 F.3d 1338, 1344 (Fed. Cir. 2012). As specif-
ically related to Walker Process fraud, “[t]o establish
monopolization or attempt to monopolize a part of trade or
commerce under § 2 of the Sherman Act, it [is] necessary to
appraise the exclusionary power of the illegal patent claim
in terms of the relevant market for the product involved.”
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 31
Walker Process, 382 U.S. at 177. “Without a definition of
the relevant market, the anticompetitive effects of an im-
properly obtained patent are impossible to measure.”
Delano Farms Co. v. Cal. Table Grape Comm’n, 655 F.3d
1337, 1351 (Fed. Cir. 2011); see also Walker Process, 382
U.S. at 177 (explaining “there is no way to measure” likeli-
hood of monopoly without defining relevant market).
Identifying the relevant market requires determining
both the relevant product and the relevant geography. See
Spectrum Sports, 506 U.S. at 459 (“[D]emonstrating the
dangerous probability of monopolization in an attempt case
also requires inquiry into the relevant product and geo-
graphic market.”); see also DSM Desotech Inc. v. 3D Sys.
Corp., 749 F.3d 1332, 1339 (Fed. Cir. 2014) (“The relevant
product market consists of all products that are reasonably
interchangeable by consumers for the same purposes.”) (in-
ternal quotation marks omitted). “Definition of the rele-
vant market is a question of fact.” IGT, 702 F.3d at 1344;
see also C.E. Servs., Inc. v. Control Data Corp., 759 F.2d
1241, 1245 (5th Cir. 1985) (describing “determination of
relevant market” as inherently “fact-specific” exercise).
The parties here advanced competing market defini-
tions. Global Tubing sought to define the relevant market
narrowly, as limited to the United States and quenched-
and-tempered coiled tubing. J.A. 5993-95 (“Q&T coiled
tubing constitutes [the] relevant product market.”); J.A.
6010 (“[I]t is effectively a United States relevant geo-
graphic market.”). Tenaris, by contrast, proposed that the
relevant market be defined as the global market for all
types of coiled tubing, including conventional, quenched-
and-tempered, and “stick pipe.” J.A. 5785-93. Both parties
introduced evidence that, if credited by a reasonable jury,
would support its market definition. Compare, e.g., J.A.
5993-95 (Global Tubing expert opining that proper market
is quenched-and-tempered coiled tubing sold in U.S.) with
J.A. 5785-93 (Tenaris expert opining that proper market is
worldwide market for quenched-and-tempered,
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 32
conventional, and “stick pipe” coiled tubing). The parties’
competing evidence as to the relevant product and geo-
graphic market created genuine disputes of material fact.
Rather than evaluate whether the contested record ev-
idence revealed a genuine dispute of material fact, the dis-
trict court determined that Tenaris is “a small market
player” posing no dangerous probability of monopolizing
the market. J.A. 31191. It did so without defining the rel-
evant market, either in terms of product or geography, and
without confirming the lack of a genuine dispute on these
material issues.
The district court did not cite any authority, and we are
aware of none, holding that an alleged attempted monopo-
list must hold a minimum market share in order for a Sher-
man Act violation to be proven. See, e.g., Domed Stadium
Hotel, Inc. v. Holiday Inns, Inc., 732 F.2d 480, 490 (5th Cir.
1984) (“[W]e must be particularly wary of the numbers
game of market percentage when considering an attempt
to monopolize suit.”) (internal quotation marks omitted);
see also C.A.T. Indus. Disposal, Inc. v. Browning-Ferris In-
dus., Inc., 884 F.2d 209, 211 (5th Cir. 1989) (per curiam)
(“[T]he exact market share percentage necessary to prove
an attempt to monopolize may vary under different market
conditions.”). Given the genuine disputes as to the mate-
rial facts of the relevant product and geographic markets,
we are not persuaded that, as a matter of law, Tenaris’ al-
leged 29% market share is per se too small to create a “dan-
gerous probability” that Tenaris might obtain a monopoly.
See Domed Stadium, 732 F.2d at 490 (“[A] share of less
than the fifty percent generally required for actual monop-
olization may support a claim for attempted monopoliza-
tion if other factors such as concentration of market, high
barriers to entry, consumer demand, strength of the com-
petition, or consolidation trend in the market are pre-
sent.”); see also Dimmitt Agri Indus., Inc. v. CPC Int’l Inc.,
679 F.2d 516, 533 n.18 (5th Cir. 1982) (“Relative to market
share requisites for the completed monopolization offense,
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 33
minimum market shares for the attempt offense are much
more unsettled.”).
C
There is a further genuine dispute as to the material
fact of whether Tenaris “has engaged in predatory or anti-
competitive conduct.” Spectrum, 506 U.S. at 456. Taking
the evidence in the light most favorable to Global Tubing,
a reasonable factfinder could find that Tenaris did so. One
could reasonably reach this conclusion based on record ev-
idence suggesting that Tenaris intended to sue Global Tub-
ing for infringement of the (allegedly) fraudulently
acquired ’256 patent.
A Global Tubing employee, Garry McClelland, testified
in deposition that, at a trade show in 2017, Tenaris’ chief
technology officer (and coinventor on the ’256 patent),
Bruce Reichert, said to him: “I can tell you right now we’re
probably going to court.” J.A. 10830. McClelland added
that he was repeatedly asked by customers at that same
show, “Are you getting sued? Are you being sued? What
about Tenaris’ patent?” J.A. 10831. McClelland’s under-
standing was that “someone at Tenaris call[ed] [Global
Tubing’s] DURACOIL a copycat” of BlueCoil. J.A. 10830.
There is also evidence that, around this same time in
March 2017, preparations were being made at Tenaris to
sue Global Tubing for infringement of the ’256 patent. See,
e.g., J.A. 10869 (Tenaris employees anticipating “future le-
gal battle ahead” in connection with DURACOIL); J.A.
10873 (coinventor of ’256 patent proposing strategy for “de-
fending [our] patent and reflect[ing] that we cover what
[Global] do[es]”); see also J.A. 10874 (“[G]iven the permea-
bility of this market and the speed at which those who copy
move, we must make an effort to stop them with our [pa-
tent] rights.”).
Because a reasonable factfinder, taking the record evi-
dence in the light most favorable to Global Tubing as the
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 34
non-movant, could find that Tenaris threatened and in-
tended to sue Global Tubing on its patents, and could fur-
ther find that those patent rights were obtained by
committing fraud on the PTO, Tenaris was not entitled to
a grant of summary judgment on the Walker Process fraud
claim.
D
There may be yet another genuine dispute of material
fact. This one relates to the proper date at which to meas-
ure Tenaris’ share of the relevant market, however that
market is defined. “[W]e look to the defendant’s conduct
and the market at the time the conduct occurred, rather
than evaluating the conduct’s effects after-the-fact.” Tay-
lor Pub. Co. v. Jostens, Inc., 216 F.3d 465, 475 (5th Cir.
2000); see also United States v. Am. Airlines, Inc., 743 F.2d
1114, 1118 (5th Cir. 1984) (“When evaluating the element
of dangerous probability of success, we do not rely on hind-
sight but examine the probability of success at the time the
acts occur.”). Global Tubing argues that the district court
wrongly evaluated Tenaris’ market share as of 2019, after
a third party, Quality Tubing, had entered the quenched-
and-tempered coiled tubing market. According to Global
Tubing, the court should have instead looked to the state
of the market in 2017, when Tenaris’ alleged misconduct –
the assertion of its allegedly fraudulently-obtained patents
– began. The district court may have to evaluate the merits
of this argument on remand.
For at least these reasons, summary judgment should
not have been granted to Tenaris on Global Tubing’s
Walker Process fraud claim.
V
We have considered the parties’ remaining arguments
and find them unpersuasive. Accordingly, we vacate the
district court’s grant of summary judgment to Global Tub-
ing on its inequitable conduct claim, as well as the grant of
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GLOBAL TUBING LLC v. TENARIS COILED TUBES LLC 35
summary judgment to Tenaris on Global Tubing’s Walker
Process fraud claim. We affirm the district court’s denial
of summary judgment to Tenaris of no inequitable conduct,
since the evidence could support a finding of intent to de-
fraud the PTO by withholding a material prior art refer-
ence. We remand for further proceedings consistent with
this opinion.
AFFIRMED-IN-PART AND VACATED-AND-
REMANDED-IN-PART
COSTS
Each party to bear its own costs.
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