Shockwave Medical, Inc. v. CARDIOVASCULAR SYSTEMS, INC., Cross-Appellant COKE MORGAN STEWART, ACTING UNDER…

United States Court of Appeals
for the Federal Circuit
______________________
SHOCKWAVE MEDICAL, INC.,
Appellant
v.
CARDIOVASCULAR SYSTEMS, INC.,
Cross-Appellant
COKE MORGAN STEWART, ACTING UNDER
SECRETARY OF COMMERCE FOR
INTELLECTUAL PROPERTY AND ACTING
DIRECTOR OF THE UNITED STATES PATENT
AND TRADEMARK OFFICE,
Intervenor
_____________________
2023-1864, 2023-1940
______________________
Appeals from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in No. IPR2019-
00405.
______________________
Decided: July 14, 2025
______________________
DAVID C. MCP HIE , Irell & Manella LLP, Newport
Beach, CA, argued for appellant. Also represented by
STEPHEN P AYNE ; MICHAEL R ICHARD F LEMING, Washington,
DC; C OOK A LCIATI, Gardella Grace PA, Washington, DC.
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GABRIEL K. BELL, Latham & Watkins LLP, Washing-
ton, DC, argued for cross-appellant. Also represented by
HANNAH FAN, MICHAEL A. MORIN, J ACOB VANNETTE .
MAUREEN DONOVAN QUELER , Office of the Solicitor,
United States Patent and Trademark Office, Alexandria,
VA, argued for intervenor. Also represented by P ETER J.
A YERS, MAI -TRANG DUC DANG, AMY J. NELSON.
______________________
Before L OURIE , DYK, and C UNNINGHAM , Circuit Judges.
DYK, Circuit Judge.
In an inter partes review (“IPR”), the Patent Trial and
Appeal Board (“Board”) determined that claims 1–4 and 6–
17 of U.S. Patent No. 8,956,371 (the “’371 patent”) were
shown to be unpatentable as obvious but that claim 5 was
not shown to be unpatentable as obvious. Patent owner
Shockwave Medical, Inc. (“Shockwave”) appeals the
Board’s determinations as to claims 1–4 and 6–17, and IPR
petitioner Cardiovascular Systems, Inc. (“CSI”) cross-ap-
peals the Board’s determination as to claim 5. We affirm
the Board’s determination that claims 1–4 and 6–17 were
shown to be unpatentable and reverse the Board’s determi-
nation that claim 5 was not shown to be unpatentable. We
accordingly affirm as to Shockwave’s direct appeal and re-
verse as to CSI’s cross-appeal.
B ACKGROUND
Shockwave owns the ’371 patent, entitled “Shockwave
Balloon Catheter System,” which is directed to the treat-
ment of atherosclerosis through intravascular lithotripsy
(“IVL”). Atherosclerosis is a common health condition
characterized by the buildup of fatty deposits in blood ves-
sels. These deposits may gradually harden into calcified
atherosclerotic plaque and restrict blood flow, causing
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coronary artery disease or vascular disease. Balloon angi-
oplasty is a well-known method of treating atherosclerosis
and involves guiding a balloon catheter to the location of
the blood vessel that contains the calcified plaque buildup:
Once in place, the balloon is inflated, widening the blood
vessel and increasing blood flow. A typical balloon catheter
is the over-the-wire balloon catheter, which consists of a
hollow carrier (called a lumen), which is inserted over a
wire to guide the balloon catheter to the correct position.
Lithotripsy is a well-known technique used in the
treatment of kidney stones. It involves sending shock-
waves—a form of high-intensity sonic wave—directly to-
ward kidney stones. These shockwaves are induced by
plasma, which is produced either by an electrical charge
(known as electrohydraulic lithotripsy) or laser (known as
laser lithotripsy). The shockwaves break up larger stones
into smaller stones, allowing them to pass through the uri-
nary system. The ’371 patent applies this technique to
breaking up calcified plaque deposits in the context of
treating atherosclerosis, disclosing a method for treating
atherosclerosis through electrohydraulic lithotripsy.
The claimed device uses a typical over-the-wire angio-
plasty balloon catheter and adds electrodes and a pulse
generator. See ’371 patent, col. 4 ll. 10–14. The patent ex-
plains that the electrodes within the fluid-filled balloon are
attached to the pulse generator and that the electrodes pro-
duce electrical arcs that “are used to generate shockwaves
in the fluid.” ’371 patent, col. 4 ll. 17–18. These shock-
waves are conducted to the location of the vessel wall con-
taining the calcified plaque deposits, where “the energy . . .
break[s] the hardened plaque without the application of ex-
cessive pressure by the balloon on the walls of the artery.”
’371 patent, col. 4 ll. 36–41.
Claim 1 is exemplary as to the claims in Shockwave’s
appeal and recites:
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1. An angioplasty catheter comprising:
an elongated carrier sized to fit within a
blood vessel,
said carrier having a guide wire lumen ex-
tending there through;
an angioplasty balloon located near a distal
end of the carrier with a distal end of the
balloon being sealed to the carrier near the
distal end of the carrier and with a proxi-
mal end of the balloon defining an annular
channel arranged to receive a fluid therein
that inflates the balloon; and
an arc generator including a pair of elec-
trodes,
said electrodes being positioned within and
in non-touching relation to the balloon,
said arc generator generating a high volt-
age pulse sufficient to create a plasma arc
between the electrodes resulting in a me-
chanical shock wave within the balloon
that is conducted through the fluid and
through the balloon and wherein the bal-
loon is arranged to remain intact during
the formation of the shockwave.
’371 patent, col. 6 ll. 21–39.
Claim 2 depends from claim 1 and requires that the
“pair of electrodes” include a “pair of metallic electrodes.”
See id. col. 6 ll. 40–41. Claim 5 depends from claim 2 and
is the subject of CSI’s cross-appeal. Claim 5 recites:
5. The catheter of claim 2, wherein the pair of elec-
trodes is disposed adjacent to and outside of the
guide wire lumen.
Id. col. 6 ll. 46–47.
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In December 2018, CSI filed an IPR petition challeng-
ing all 17 claims of the ’371 patent as obvious over various
prior art combinations. CSI’s primary prior art reference
was European Patent Application Publication
No. EP 0571306 A1 (“Levy”), which describes using laser-
generated pulses to disintegrate plaque in blood vessels.
CSI also pointed to the ’371 patent’s disclosure of “typical
prior art over-the-wire angioplasty balloon catheters[s] . . .
[that] are usually non-compliant with a fixed maximum di-
mension when expanded with a fluid such as saline.”
J.A. 354 (quoting ’371 patent, col. 3 l. 65–col. 4 l. 2). CSI
argued that it would have been obvious to an ordinarily
skilled artisan to modify Levy with the well-known angio-
plasty balloon catheter disclosed by the applicant admitted
prior art (“AAPA”). Its proffered prior art combinations
(which are the subject of the appeal and cross-appeal) in-
volved “Levy as modified by AAPA” in combination with
other prior art references. J.A. 337–38.
In July 2020, the Board issued its Final Written Deci-
sion, finding that claims 1–4 and 6–17, but not claim 5,
were shown to be unpatentable as obvious. The Board de-
termined that AAPA qualified as “prior art consisting of
patents or printed publications” under 35 U.S.C. § 311(b).
On August 18, 2020, the Patent and Trademark Office
(“PTO”) issued binding guidance (the “AAPA Guidance”)
stating that AAPA is not “prior art consisting of patents or
printed publications” under § 311(b). J.A. 10730. The
Board thereafter initiated rehearing “to allow the panel to
consider and follow the AAPA Guidance.” J.A. 1081. In
February 2023, the Board issued its Final Decision on Re-
hearing, relying on AAPA only as evidence of the back-
ground knowledge in the art as to typical over-the-wire
balloon catheters and again determining that claims 1–4
and 6–17 had been shown to be unpatentable as obvious
but that claim 5 had not.
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Shockwave appeals, and CSI cross-appeals. We have
jurisdiction under 28 U.S.C. § 1295(a)(4)(A).
DISCUSSION
“Obviousness is a mixed question of fact and law.” No-
vartis AG v. Torrent Pharms. Ltd., 853 F.3d 1316, 1327
(Fed. Cir. 2017). We review the Board’s legal conclusion of
obviousness de novo and its factual findings for substantial
evidence. Okajima v. Bourdeau, 261 F.3d 1350, 1354
(Fed. Cir. 2001). Claim construction is an issue of law that
we review de novo when based on intrinsic evidence. Per-
sonalized Media Commc’ns, LLC v. Apple, Inc., 952 F.3d
1336, 1339 (Fed. Cir. 2020). “What a prior art reference
teaches and whether a skilled artisan would have been mo-
tivated to combine references are questions of fact[]” that
we review for substantial evidence. Apple Inc. v. Samsung
Elecs. Co., 839 F.3d 1034, 1051 (Fed. Cir. 2016).
I
A
Shockwave argues that both CSI in its petition and the
Board in its final written decision improperly relied on
AAPA to supply a basis for the petition. We disagree.1
Section 311(b) of the Patent Act provides: “A petitioner
in an inter partes review may request to cancel as
1 CSI contends that that the Board’s conclusion that
the petition met the threshold requirements under § 311(b)
is not appealable under § 314(d). As we explained in Qual-
comm Incorporated v. Apple Inc., 134 F.4th 1355 (Fed. Cir.
2025), this type of § 311(b) challenge is directed to the
Board’s final written decision, not “to the Board’s determi-
nation about a run-of-the-mill statutory provision of a pro-
cedural nature regarding the threshold decision of whether
to institute an IPR.” Id. at 1364.
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unpatentable 1 or more claims of a patent only on a ground
that could be raised under section 102 or 103 and only on
the basis of prior art consisting of patents or printed publi-
cations.” 35 U.S.C. § 311(b). We have explained that
“[a]lthough the prior art that can be considered in [IPRs] is
limited to patents and printed publications, it does not fol-
low that we ignore the skilled artisan’s knowledge when
determining whether it would have been obvious to modify
the prior art.” Koninklijke Philips N.V. v. Google LLC,
948 F.3d 1330, 1337 (Fed. Cir. 2020). This is because the
obviousness analysis “requires an assessment of the . . .
‘background knowledge possessed by a person having ordi-
nary skill in the art.’” Dow Jones & Co. v. Ablaise Ltd.,
606 F.3d 1338, 1349 (Fed. Cir. 2010) (quoting KSR Int’l Co.
v. Teleflex, Inc., 550 U.S. 398, 401 (2007)).
AAPA is art referenced in a patent application that is
admitted by the applicant to be prior art. We recently ap-
proved the role of AAPA as evidence of general background
knowledge of an ordinarily skilled artisan in our decisions
in Qualcomm Incorporated v. Apple Inc., 24 F.4th 1367
(Fed. Cir. 2022) (“Qualcomm I”), and Qualcomm Incorpo-
rated v. Apple Inc., 134 F.4th 1355 (Fed. Cir. 2025) (“Qual-
comm II”).
In Qualcomm I, the IPR petitioner challenged a pa-
tent’s claims as obvious based on the patent’s description
of a prior art system in combination with a prior art patent,
and the Board found the claims to be unpatentable.
24 F.4th at 1371–72. We held that AAPA may be used as
evidence of background knowledge of an ordinarily skilled
artisan, but that AAPA cannot be the “basis” of a ground in
an IPR petition. Id. at 1377. Because the Board had not
addressed the issue whether the AAPA formed the basis of
the petition, we remanded to allow the Board to address
this issue in the first instance. See id. On remand, the
Board held that AAPA does not form the basis of a ground
in violation of § 311(b) if the ground relies on the AAPA “in
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combination with” permissible prior art patents or printed
publications. Qualcomm II, 134 F.4th at 1360. Based on
this interpretation, the Board found that the ground relied
upon by the petitioner was compliant with § 311(b). On a
second appeal, we reversed, since the IPR petitioner had
expressly labeled the AAPA as part of its “basis” for its ob-
viousness ground. Id. at 1368.
Our decisions in Qualcomm I and Qualcomm II accord-
ingly require that only patents and printed publications
form the basis of an IPR petition’s unpatentability grounds.
However, AAPA can be important evidence of general back-
ground knowledge, and general knowledge can be used to
supply a missing claim limitation. As we explained in
Qualcomm I, our case law has long recognized numerous
permissible uses for general background knowledge in an
IPR such as, “for example, furnishing a motivation to com-
bine, or supplying a missing claim limitation.” 24 F.4th
at 1376 (first citing Randall Mfg. v. Rea, 733 F.3d 1355,
1362 (Fed. Cir. 2013); and then citing Koninklijke,
948 F.3d at 1337–38). In Qualcomm II, we reiterated that
AAPA can be used “to indicate the general knowledge of a
person of ordinary skill in the art.” 134 F.4th at 1365.
This case is quite different from Qualcomm II, where
the petitioner expressly labeled AAPA as the “basis” for its
challenge. 134 F.4th at 1367. Here CSI used AAPA only
to show, as the ’371 patent itself acknowledged, that the
over-the-wire angioplasty balloon catheter was well known
in the prior art and that this general background
knowledge satisfied the ’371 patent’s claim limitations re-
lating to an over-the-wire configuration. See J.A. 357 (“It
would have been obvious for the POSITA to have imple-
mented and utilized the most common angioplasty catheter
and balloon design, with predictable and expected re-
sults.”). This is consistent with our decision in Koninklijke,
where we held that it is permissible for “general knowledge
to supply a missing claim limitation in an [IPR],” 948 F.3d
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at 1337–38, and our decision in Qualcomm I, where we ex-
plained it is permissible for the use of AAPA as general
knowledge “supplying a missing claim limitation,” 24 F.4th
at 1376; accord Qualcomm II, 134 F.4th at 1365.
Shockwave also urges that this case is like Qual-
comm II because the Board’s Final Written Decision uses
the word “basis” in a table describing the list of prior art
references:
Appellant’s Reply Br. 5 (citing J.A. 3–4 (alterations in orig-
inal)).
The Board’s reference table using the term “Refer-
ence(s)/Basis” does not support Shockwave’s position. It is
true that in Qualcomm II, we relied on “the statements
from the tables in [the petitioner’s] petitions clearly desig-
nat[ing] AAPA as included in the basis of Ground 2.”
134 F.4th at 1367. But our reasoning in that case was
predicated on the notion that an IPR petitioner, not the
Board, “should be held to the phrasing of its petition be-
cause [it] is the ‘master of its own petition.’” Id. (quoting
Intuitive Surgical, Inc. v. Ethicon LLC, 25 F.4th 1035, 1041
(Fed. Cir. 2022)). We have consistently explained that “it
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is the petition, not the Board’s ‘discretion,’ that defines the
metes and bounds of an [IPR].” Koninklijke, 948 F.3d
at 1336. What matters for the purposes of § 311(b) is the
grounds raised in the petition, and CSI’s petition never
phrased the AAPA in terms of constituting a basis for its
obviousness arguments. In any event, the use of the term
“references/basis” in the table suggests that it encompasses
the use of AAPA as a “reference” to establish well-known
general knowledge.
Shockwave also argues that, even if CSI did not ex-
pressly label its use of AAPA as evidence of general
knowledge of an over-the-wire balloon catheter as a basis,
in “substance” it formed the basis of the IPR petition. See
Appellant’s Br. 22. We have not previously decided
whether AAPA improperly forms the basis for a petition
when it is used to show that a claim limitation (character-
ized by the patent as not disclosed in the prior art) would
have been obvious over the prior art. That is not the case
here, where CSI properly relied on general background
knowledge to supply missing claim limitations (which
Shockwave does not argue were novel to the invention) and
used AAPA as evidence of that general background
knowledge. The IPR petition did not violate § 311(b).
B
Shockwave argues that the Board erred in denying its
construction for “angioplasty balloon” as “a balloon that
displaces the plaque into the vessel wall to expand the lu-
men of the vessel” and adopting CSI’s construction of the
term as “an inflatable sac that is configured to be inserted
into a blood vessel for use in a medical procedure to widen
narrowed or obstructed blood vessels.” J.A. 11. According
to Shockwave, the Board’s adoption of CSI’s construction
fails to give proper meaning to the word “angioplasty,” and
Shockwave urges that the Board’s construction effectively
construes angioplasty to encompass “any type of procedure
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that widens obstructed blood vessels and includes a balloon
in some capacity.” Appellant’s Br. 30.
Nothing in the language of the claims or specification
supports requiring that an angioplasty balloon press
plaque into the vessel wall. In fact, the specification states
that, although the balloon can be “expanded to fit snugly to
the vessel wall[,] . . . this is not a requirement.” ’371 pa-
tent, col. 5 ll. 31–33. The specification also includes exam-
ples that describe widening the blood vessel without
displacing plaque “into” the vessel wall. It explains that
the plaque is “pulverized by the shock waves,” ’371 patent
col. 5 ll. 45–46, so as to “break the hardened plaque without
the application of excessive pressure by the balloon on the
walls of the artery,” id. col. 4 ll. 39–41. These examples
contemplate situations where the balloon catheter widens
the blood vessel without needing to press the plaque into
the vessel wall.
To the extent that Shockwave urges that it “dis-
claime[d]” claim scope to overcome a prior art rejection and
that an “angioplasty balloon” thus requires displacing
plaque into the vessel, see Appellant’s Br. 32, we disagree.
Shockwave simply added the term “angioplasty” to the
claim language and on appeal does not point to any portion
of the prosecution history in which it mentioned requiring
the angioplasty balloon to displace the plaque “into the ves-
sel wall” or any equivalent language thereof.
C
Finally, Shockwave challenges three of the Board’s fact
findings: (1) that an ordinarily skilled artisan would have
been motivated to incorporate Levy’s shockwave system
into the over-the-wire balloon catheter, (2) that Levy dis-
closes shockwaves, and (3) that Shockwave’s secondary
considerations evidence did not outweigh CSI’s obvious-
ness showing. Substantial evidence supports each of these
findings.
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Shockwave’s first two challenges to the Board’s factual
findings relate to Levy. Levy discloses a method for “re-
moving plaque deposits in blood vessels” using a “pulsed
laser radiation [that] is sent to an optical fiber having a
distal end immersed in a liquid at the location of such a
deposit.” JA 1735. This “causes a cavitation of vapor
within the liquid, which results in the implosion of gas bub-
bles, the implosion causing erosion of the deposit exposed
to the cavitation phenomenon.” JA 1735. Levy builds upon
and incorporates a prior reference—U.S. Patent
No. 5,116,227 (“Levy ’227”)—which is directed to a similar
use of cavitation for cleaning tooth canals.
First, Shockwave argues that, even if CSI properly re-
lied on the general knowledge to establish the balloon cath-
eter limitations, it failed to provide any evidence or
reasoning of a motivation to combine the balloon catheter
with Levy. Appellant’s Br. 37. But the Board expressly
described at least two reasons why an ordinarily skilled ar-
tisan would combine the two: (1) “to assist a physician to
navigate the catheter to reach the area for treatment” and
(2) “to increase the types of treatments Levy could per-
form.” J.A. 39–40. The Board was also entitled to credit
CSI’s expert witness Dr. Jensen’s testimony that “[i]t
would have been obvious for the person of ordinary skill in
the art to have implemented and utilized the most common
angioplasty catheter and balloon design, with predictable
and expected results.” J.A. 1645.
Second, Shockwave argues that the Board failed to
identify evidence in the record that the cavitation disclosed
in Levy by pulsed laser radiation is a high-energy shock-
wave, as opposed to a lower-energy acoustic wave (such as
a hydraulic wave). Appellant’s Br. 44. Acknowledging that
Levy ’227 references shockwaves, Shockwave nevertheless
contends that shockwaves are only referenced with respect
to a tooth canal embodiment.
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The Board did not err in finding that Levy discloses the
use of shockwaves in blood vessels. There is no question
that Levy incorporates Levy ’227 by reference. Levy ’227
teaches that “cleaning of [tooth] canal 1 is achieved by
shockwaves resulting from the laser radiation pulses, pro-
ducing vapor implosions which detach debris or tissue from
the wall of canal 1,” and that this same technique “can also
be employed in the medical field for cleaning vessels, such
as blood vessels.” J.A. 3657, col. 4 ll. 64–65. In any event,
the Board found that an ordinarily skilled artisan would
have been motivated to incorporate the arc generators in
any of Japanese Laid Open Application No. JP 62-275446
A (“Uchiyama”), U.S. Application Publication
No. 2010/0036294 A1 (“Mantell”), and German Patent Ap-
plication Publication No. DE 3038445 A1 (“Willneff”) into
Levy to arrive at the claimed shockwaves. See J.A. 30–31.
Finally, Shockwave takes issue with the Board’s find-
ings that Shockwave was not entitled to a presumption of
nexus with respect to secondary considerations and that its
objective indicia evidence did not outweigh CSI’s evidence
of obviousness. Appellant’s Br. 53, 55. Before the Board,
Shockwave sought a presumption of nexus based on a sin-
gle paragraph of its expert Dr. Berger’s declaration, who
stated that “the Shockwave IVL devices include each fea-
ture recited in the claims.” J.A. 7539. The Board’s conclu-
sion that Dr. Berger’s declaration did not sufficiently link
the claims to the structure of Shockwave’s commercial de-
vice was supported by substantial evidence, see J.A. 141–
44, since Dr. Berger conceded that he had only seen Shock-
wave’s device in pictures and could not identify who pre-
pared the claim charts he cited. See Polaris Indus., Inc.
v. Arctic Cat, Inc., 882 F.3d 1056, 1072 (Fed. Cir. 2018) (ex-
plaining that a patentee is entitled to a presumption of
nexus only “when the patentee shows that the asserted ob-
jective evidence is tied to a specific product and that prod-
uct ‘embodies the claimed features’” (quoting Brown &
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Williamson Tobacco Corp. v. Philip Morris Inc., 229 F.3d
1120, 1130 (Fed. Cir. 2000)).
We also see no problem in the Board’s analysis of
Shockwave’s purported objective indicia, which it found to
be cumulatively “largely weak.” J.A. 65. This case is not,
as Shockwave contends, like Volvo Penta of the Americas,
LLC v. Brunswick Corp., 81 F.4th 1202, 1213 (Fed. Cir.
2023), where we concluded that the Board failed to conduct
a “reasoned, collective weighing” of secondary considera-
tions evidence because it assigned “only vague weights . . .
to the various factors and fail[ed] to explain its overall sum-
mation.” The Board analyzed each of the factors in detail
and explained how much weight it accorded to each of
them. See J.A. 144–59. And unlike Volvo, 81 F.4th
at 1213, the Board did explain its summation: It explained
that although Shockwave’s evidence was “voluminous,” it
was “largely weak” because it was directed to “excitement
about the potential efficacy of the Shockwave IVL or its po-
tential commercial success.” J.A. 159.
II
The sole focus of CSI’s cross-appeal is the Board’s con-
clusion that claim 5 had not been shown to be unpatentable
as obvious over Levy implemented in an over-the-wire bal-
loon catheter in view of Uchiyama. The Board found that
the prior art combination did not disclose claim 5’s limita-
tion relating to the placement of electrodes. As a threshold
matter, Shockwave argues that CSI lacks standing to pur-
sue its appeal in this court. Appellant’s Reply Br. 42.
A
“Although a party does not need Article III stand-
ing . . . to obtain a Board decision, a party must establish
Article III standing once it seeks review of a Board decision
in this Court.” Incyte Corp. v. Sun Pharm. Indus., Inc.,
136 F.4th 1096, 1099 (Fed. Cir. 2025). Parties seeking
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relief before this court bear the burden of establishing the
existence of an Article III case or controversy “at all times
throughout the appeal.” ModernaTx, Inc. v. Arbutus Bio-
Pharma Corp., 18 F.4th 1352, 1358 (Fed. Cir. 2021). When
a party challenging an IPR decision “relies on potential in-
fringement liability as a basis for injury in fact, but is not
currently engaging in infringing activity, it must establish
that it has concrete plans for future activity that creates a
substantial risk of future infringement or would likely
cause the patentee to assert a claim of infringement.” Gen.
Elec. Co. v. Raytheon Techs. Corp., 983 F.3d 1334, 1341
(Fed. Cir. 2020) (quoting JTEKT Corp. v. GKN Auto, LTD.,
898 F.3d 1217, 1221 (Fed. Cir. 2018)).
CSI argues that it has standing to bring its cross-ap-
peal because it has developed an IVL device that is in its
final stages, see ECF No. 20-3 (declaration of Matt Cam-
bronne), at 4, and because Shockwave’s President publicly
stated that the company would aggressively assert claim 5
of the ’371 patent against competitors in the IVL market:
We are very pleased that the [Board] validated
claim 5 of our ’371 patent, which protects the broad
embodiment of our IVL technologies. Specifically,
claim 5 describes a device that is delivered over a
guidewire and generates shockwaves with elec-
trodes inside of a balloon catheter. We believe that
any viable, much less commercially viable, IVL de-
vice must contain these elements[.] . . . We believe
that our robust portfolio of 40 issued U.S. patents
and 50 issued foreign patents captures and protects
the truly unique and sophisticated IVL technol-
ogy[.]
ECF No. 20-2, at 7 (declaration of Gabriel K. Bell). These
facts, according to CSI, demonstrate that it had concrete
plans to offer a product that would likely cause Shockwave
to assert a claim of infringement of claim 5. Shockwave
responds that at the time CSI filed its cross-appeal, CSI’s
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IVL development was not sufficiently concrete to establish
standing. See Appellant’s Reply Br. 43–44.
Shockwave’s arguments rely primarily on CSI’s repre-
sentations to the Board, well before CSI filed this cross-ap-
peal. At the time it filed the cross-appeal, however, CSI
had engaged with the Food and Drug Administration sev-
eral times and was close to initiating clinical trials of an
IVL product. ECF No. 20-3 at 4; Cross-Appellant’s Reply
Br. 5–6. At the time of the cross-appeal, CSI’s product was
near a design freeze, and “[c]hanges after this point are
typically minimal.” Id. These facts are thus not like those
in Incyte, where the party had only allocated a small
amount of funds a month before filing an appeal and was
facing “significant manufacturing, formulation, testing,
and regulatory hurdles to bring [the] product to market.”
136 F.4th at 1102. Far from merely “amount[ing] to an ex-
pression of intent” to create a potentially infringing prod-
uct, id., the circumstances here constitute sufficiently
“concrete plans.” Gen. Elec., 983 F.3d at 1341.
CSI also has established a substantial likelihood of a
suit for infringement of claim 5. Shockwave has stated
that “we believe that any viable, much less commercially
viable, IVL device must contain these elements [of
claim 5],” ECF No. 20-2, at 6, and that “[w]hile we are ex-
tremely bullish about our patent portfolio in the electrohy-
draulic lithotripsy area, . . . we’ll certainly assert that
against anybody who tries to copy what we’re doing,” id.
at 30. Although a company’s representations about its in-
tent to protect its intellectual property do not always give
rise to a substantial likelihood of litigation, Shockwave’s
President’s broad claims reflect the company’s expansive
view of claim 5 as reading broadly on IVL technology. CSI
has sufficiently shown that it is engaging in “activity that
creates a substantial risk of future infringement” that is
“likely [to] cause the patentee to assert a claim of infringe-
ment.” Gen. Elec., 983 F.3d at 1341; see also CQV Co.
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v. Merck Pat. GmbH, 130 F.4th 1344, 1349 (Fed. Cir. 2025);
Adidas AG v. Nike, Inc., 963 F.3d 1355, 1357 (Fed. Cir.
2020).
B
On the merits, CSI argues that the Board failed to con-
sider the teachings of the prior art when considered as a
whole in analyzing CSI’s proffered combination of Levy as
implemented in an over-the-wire balloon catheter in view
of Uchiyama, as well as that claim 5’s pair of electrodes
“adjacent to and outside of the guidewire lumen” was a rou-
tine design choice that would have been obvious. Cross-
Appellant’s Br. 71. We agree.
Uchiyama is a printed Japanese Patent Application di-
rected to a “[d]ischarge lithotriptor” that is used “to break
a renal calculus formed in a kidney or a urinary duct in a
body cavity with impact waves generated by electric dis-
charge.” J.A. 1783. This lithotriptor was composed of a
pair of electrodes on a tube, with the electrodes located in
a fluid-inflatable balloon such that they generated a shock-
wave through the fluid of the inflated balloon. Uchiyama
taught that placing the electrodes within the balloon would
prevent discharge sparks from directly hitting human tis-
sue and thus that the shockwaves could be used to disrupt
calcifications without damaging surrounding human tis-
sue. J.A. 1785.
In its IPR petition, CSI argued that it would have been
obvious to an ordinarily skilled artisan to implement the
features of Uchiyama to provide Athat the electrodes are
radially spaced away from the lumen tube and that this
would be a routine design choice well within the ordinary
skill of the art. J.A. 364. CSI’s expert Dr. Jensen testified
that this modification would be beneficial because an ordi-
narily skilled artisan “would have understood that calcifi-
cations are not distributed uniformly within the
circumference of a vessel,” that “Uchiyama taught that the
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electrodes did not need to be centered within the balloon,”
and that an ordinarily skilled artisan would thus “have un-
derstood from Uchiyama that the electrodes could be dis-
place[d] radially away from the lumen to, for example,
permit the shockwaves to obtain greater lateral (i.e., side-
ways) coverage.” J.A. 4071. The Board found that CSI had
failed to demonstrate the placement of electrodes claimed
by claim 5 was obvious, on the ground that the electrodes
in Uchiyama itself were not placed both adjacent to and ra-
dially away from the lumen, a finding we do not disturb
here. J.A. 69–70.
The problem with the Board’s analysis is that it was
predicated on its finding that Uchiyama alone did not dis-
close that the electrodes were positioned “adjacent to and
outside of the guidewire lumen,” since the argument raised
by CSI before the Board was based on the combined teach-
ings of Levy as modified by an over-the-wire catheter bal-
loon and Uchiyama. The standard for obviousness requires
consideration of the prior art combination taken as a whole.
In re Mouttet, 686 F.3d 1322, 1331 (Fed. Cir. 2012).
The Board’s failure to consider the combined teachings
of the prior art led it to improperly discount CSI’s argu-
ment in its petition that modifying Uchiyama to place the
electrodes outside the lumen would have been a routine de-
sign choice. “When there is a design need or market pres-
sure to solve a problem and there are a finite number of
identified, predictable solutions, a person of ordinary skill
has good reason to pursue the known options within his or
her technical grasp.” KSR, 550 U.S. at 421. We explained
in Uber Technologies, Inc. v. X One, Inc., 957 F.3d 1334,
1338–40 (Fed. Cir. 2020), that when there are a limited
number of well-known design choices in the prior art it
would have been obvious to substitute one for the other.
Such is the case here: CSI’s expert Dr. Jensen testified
that “it would have been obvious to a person of ordinary
skill in the art to implement the features of Uchiyama to
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provide the pair of electrodes that are disposed radially
spaced away from the lumen tube” and that “[s]uch an im-
plementation is a routine design choice and well within the
knowledge and know-how of the person of ordinary skill in
the art.” See J.A. 1653. Shockwave did not present con-
trary evidence.
The only argument that Shockwave made before the
Board against CSI’s proposed placement of the electrodes
in Levy was that it would have been located too close to the
tissue and caused damage. The Board rejected that exact
same argument in making its other obviousness findings
as to claim 1. There was thus no evidence in the record
supporting the Board’s obviousness finding as to claim 5,
and reversal rather than vacatur is thus appropriate.
C ONCLUSION
We have considered Shockwave’s remaining argu-
ments and find them unpersuasive. We accordingly affirm
the Board’s determinations as to claims 1–4 and 6–17 in
Shockwave’s direct appeal and reverse the Board’s deter-
mination as to claim 5 in CSI’s cross-appeal.
AFFIRMED-IN-PART AND REVERSED-IN-PART
C OSTS
Costs to cross-appellant CSI.
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