Asetek Danmark A/S

Patent Trials and Appeals Board

Aug 19, 2021

IPR2020-00524 (P.T.A.B. Aug. 19, 2021)

Trials@uspto.gov Paper 35
Tel: 571-272-7822 Date: August 19, 2021
UNITED STATES PATENT AND TRADEMARK OFFICE

BEFORE THE PATENT TRIAL AND APPEAL BOARD

COOLIT SYSTEMS, INC.,
Petitioner,
v.
ASETEK DANMARK A/S,
Patent Owner.

IPR2020-00524
Patent 9,733,681 B2

Before MICHAEL P. TIERNEY, Vice Chief Administrative Patent Judge,
KEVIN W. CHERRY, and JASON W. MELVIN,
Administrative Patent Judges.
CHERRY, Administrative Patent Judge.
JUDGMENT
Final Written Decision
Determining No Challenged Claims Unpatentable
35 U.S.C. § 318(a)
I. INTRODUCTION
A. BACKGROUND
CoolIT Systems, Inc. (“Petitioner”) filed a petition (Paper 2, “Pet.”) to
institute an inter partes review of claims 1, 4, 8, 11, 15, and 16 of U.S.
Patent No. 9,733,681 B2 (Ex. 1001, “the ’681 patent”). See 35 U.S.C.
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§ 311. Asetek Danemark A/S (“Patent Owner”) timely filed a Preliminary
Response. Paper 6 (“Prelim. Resp.”). We also authorized Petitioner to file a
Reply (Paper 8). Paper 7 (Order Authorizing Reply).
On August 24, 2020, based on the record before us at the time, we
instituted an inter partes review of all challenged claims on all grounds
alleged. Paper 9 (“Institution Decision” or “Dec.”). After we instituted this
review, Patent Owner filed a statutory disclaimer disclaiming claims 8–16
(Ex. 2015, “Statutory Disclaimer”). Thus, the only claims and ground
remaining in this proceeding are indicated in the table below.
Claim(s) challenged 35 U.S.C. § Reference(s)
1, 4 103(a)1 Duan,2 Shin,3 Cheon4
Petitioner supports its Petition with a Declaration by Marc Hodes,
Ph.D., dated February 7, 2020. Ex. 1003.
Patent Owner filed a Response in opposition to the Petition (Paper 21,
“PO Resp.”). Patent Owner supported its Patent Owner Response with the
Declaration of Donald E. Tilton, Ph.D., dated November 30, 2020

1 Because the claims at issue have an effective filing date prior to
March 16, 2013, the effective date of the applicable provisions of the Leahy-
Smith America Invents Act, Pub. L. No. 112-29, 125 Stat. 284 (2011)
(“AIA”), we apply the pre-AIA versions of 35 U.S.C. §§ 102 and 103 in this
Decision.
2 U.S. Patent Application Publication No. 2006/0185830, filed Feb. 18, 2005,
published Aug. 24, 2006 (Ex. 1005, “Duan”).
3 Japanese Published Patent Application 2002-151638, published May 24,
2002 (Ex. 1006, “Shin”). The record includes a certified English translation
of Shin. All citations will be to the certified English translation.
4 U.S. Patent No. 5,731,954, issued Mar. 24, 1998 (Ex. 1007, “Cheon”).
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(Ex. 2018). Petitioner filed a Reply in support of the Petition (Paper 25,
“Reply”). Petitioner supports the Reply with the Supplemental Declaration
of Marc Hodes, Ph.D. (Ex. 1013). Patent Owner filed a Sur-reply
responding to the Reply (Paper 28, “Sur-Reply”). Patent Owner did not
move to amend any claim of the ’681 patent.
Both parties requested an oral hearing. See Paper 31. A transcript of
the oral hearing is entered in the record. Paper 33 (“Tr.”).
We have jurisdiction under 35 U.S.C. § 6. The evidentiary standard is
a preponderance of the evidence. See 35 U.S.C. § 316(e) (2018); 37 C.F.R.
§ 42.1(d) (2019). This Final Written Decision is issued pursuant to
35 U.S.C. § 318(a) and 37 C.F.R. § 42.73.
For the reasons expressed below, we conclude that Petitioner has not
demonstrated by a preponderance of evidence that claims 1 and 4 (“the
remaining challenged claims”) are unpatentable.
B. RELATED PROCEEDINGS
The parties identify Asetek Danmark A/S v. CoolIT Systems, Inc., Case
No. 3:19-cv-00410-EMC (N.D. Cal.) (complaint served on February 7,
2019, currently pending) as a related co-pending district court litigation.
Pet. 1; Paper 4, 1. The parties also identify the following pending
proceedings for inter partes review involving patents that are related to the
’681 patent: IPR2020-00522; IPR2020-00523. Pet. 1; Paper 4, 1.
C. THE ’681 PATENT
The ’681 patent is titled “Cooling System for a Computer System.”
Ex. 1001, at [54]. The ’681 patent issued from Application Serial No.
13/861,593, filed April 12, 2013. Id. at [21], [22]. The ’593 application is a
continuation of Application Serial No. 11/919,974, filed on January 6, 2009,
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which is a U.S. national phase application of PCT/DK2005/00310, filed
May 6, 2005. Id. at [63].
The ’681 patent relates to a liquid-cooling system for a computer
system. Id. at [57]. The Specification explains that, at the time of the
invention, air cooling arrangements were the most-used cooling system for
cooling central processing units (CPUs) in computer systems. Id. at 1:17–
33. An alternative design known at the time of the invention was to use a
cooling liquid circulating inside a closed system by means of a pumping unit
with a heat exchanger past which the cooling liquid circulates. Id. at 1:34–
38. The Specification contends that liquid cooling is generally more
efficient and quieter than air cooling, but that a liquid cooling design
consists of “many components,” which increases the total installation time,
size, and risk of leakage of the cooling liquid from the system. Id. at 1:39–
49. Thus, it is one object of the invention to provide a small and compact
liquid-cooling solution, which is more efficient than existing air-cooling
arrangements, can be produced at low cost enabling high production
volumes, is easy to use and implement, can be used with existing CPU types
and computer systems, and requires a low level of maintenance or no
maintenance at all. Id. at 1:53–63.
An illustrative embodiment of such a systemis depicted in Figures 7
and 8, reproduced below.
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Figure 75 is a perspective view of the cooling system showing
reservoir housing 14 with heat exchanging surface 5 (shown in Figure 8) and
pump 21 (shown in Figure 8) inside the reservoir. Id. at 16:16–19. Figure 8
is a cut-out view into reservoir housing 14, when the reservoir, pump 21, and
heat exchanging surface 4 are situated inside the reservoir. Id. at 15:49–51.
The reservoir has tube inlet connection 15 (not shown in Figure 8) through
which the cooling liquid enters the reservoir. Id. at 15:51–53. From the tube

5 We agree with Petitioner that it appears that the Specification transposes
the description of Figure 7 with that of Figure 8. Pet. 5 n.1. We refer to the
description of “Figure 8” in the Specification in our discussion of Figure 7,
and we refer to the Specification’s discussion of “Figure 7” in our discussion
of Figure 8.
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inlet connection, the cooling liquid flows through the reservoir passing heat
exchanging surface 4 and enters the inlet of the pump. Id. at 15:54–56.
After the cooling liquid flows through the pump, the cooling liquid passes
out of the outlet of the pump and further out through tube outlet connection
16. Id. at 15:56–58. As shown in Figure 7, tube inlet connection 15 and
tube outlet connection 16 are connected to heat radiator 11 by means of
connecting tubes 24 and 25. Id. at 16:19–21. Cooling liquid flows into and
out of the reservoir and the heat radiator through connecting tubes 24 and
25, respectively. Id. at 16:21–23. The reservoir may be provided with
channels or segments for establishing a certain flow-path for the cooling
liquid through the reservoir to prevent the cooling liquid from passing the
reservoir too quickly to take up a sufficient amount of heat from the heat
exchanging surface. Id. at 16:51–62.
Within heat radiator 11 (shown in Figure 7), the cooling liquid passes
a number of channels for radiating the heat carried in the cooling fluid from
heat exchanging surface 4 (shown in Figure 8). Id. at 16:23–26. Air fan 10
(with propeller 23) of Figure 7 blows air past the channels of the heat
radiator in order to cool the radiator and thereby cool the cooling liquid
flowing inside the channels through the heat radiator and back into the
reservoir. Id. at 16:26–30.
Figures 17 and 20 show the internal structures of a preferred
embodiment of the reservoir according to the invention and are reproduced
below. Id. at 21:48–50.
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Figure 17 is an exploded perspective view of a preferred embodiment
of a reservoir, pump, and heat exchanging surface. Id. at 10:7–9. Figure 20
is a simplified schematic showing a cross-sectional view of the reservoir
along plane 20-20 of Figure 17. Id. at 10:16–17. Reservoir housing 14, as
shown in Figures 17 and 20, is in the form of a double-sided chassis having
a substantially conical, circular configuration with stiffening ribs 36
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extending axially along the exterior of the reservoir housing and configured
to mount an electrical motor. Id. at 21:49–57. Reservoir housing 14 has
recess 40 intended for accommodating stator 37 of electrical motor driving
impellor 33 of the pump, which is attached to shaft 38 of rotor 39 of the
electric motor. Id. at 21:58–22:1. The Specification explains that “a liquid-
proof division” is made between rotor 39 of the motor, which is submerged
in the cooling liquid, and stator 37 of the pump. Id. at 22:1–22:6.
The enclosed space between impeller 33 and heating exchanging
interface 4 is divided into two separate chambers by impeller cover 46A and
intermediate member 47, as shown in Figure 20. The chamber formed by
impeller 33 and impeller cover 46A is described as “pump chamber 46” and
has outlet 34. Id. at 22:64–67. A second chamber termed “thermal
exchange chamber 47A” is formed by intermediate member 47 and heat
exchanging interface 4. Id. at 23:5–11. Intermediate member 47 has two
passages through it—first passage 48 and second passage 49. Id. at 23:7–15.
First passage 48 connects to outlet 34 and provides a passage for the cooling
liquid to flow from pump chamber 46 to thermal exchange chamber 47A.
Id. Second passage 49 leads cooling liquid from thermal exchange chamber
47A to the interior of reservoir housing 14 allowing for the circulation of the
liquid out of reservoir housing 14 to heat radiator 11. Id. at 23:11–19.
Claim 1 is the sole independent claim among the remaining
challenged claims. Claim 4 depends from claim 1. Independent claim 1,
which is illustrative, recites:
1. A liquid cooling system for cooling a heat-generating
component of a computer, comprising:
a double-sided chassis adapted to mount a pump configured to
circulate a cooling liquid, the pump comprising a motor
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with a stator and an impeller, the impeller being positioned
on one side of the chassis and the stator being positioned
on an opposite side of the chassis and isolated from the
cooling liquid;
a reservoir adapted to pass the cooling liquid therethrough, the
reservoir including:
a pump chamber including the impeller; and
a thermal exchange chamber formed below the pump
chamber and vertically spaced apart from the pump
chamber, the pump chamber and the thermal
exchange chamber being separate enclosed
chambers that are fluidly coupled;
a heat-exchanging interface removably coupled to the
reservoir, the heat-exchanging interface forming a
boundary wall of the thermal exchange chamber
and configured to be placed in thermal contact with
a surface of the heat-generating component;
a heat radiator adapted to pass the cooling liquid
therethrough, the heat radiator being fluidly coupled
to the reservoir and positioned at a location
horizontally spaced apart from the heat-generating
component, the heat radiator being configured to
dissipate heat from the cooling liquid;
a fan configured to direct air through the heat radiator, the
fan being driven by a motor separate from the motor
of the pump; and
a control system configured to independently control a
speed of the pump and a speed of the fan;
wherein the pump chamber includes:
an inlet positioned below the center of the impeller
configured to enable the cooling liquid to
flow into the center of the pump chamber;
an outlet that fluidly couples the pump chamber to
the thermal exchange chamber via a first
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passage, the outlet is positioned along an
outer circumference of the pump chamber
and is configured to direct the cooling liquid
driven by the impeller through the first
passage to the thermal exchange chamber;
wherein the first passage directs the cooling liquid
into the thermal exchange chamber between
a first end and a second end of the thermal
exchange chamber;
wherein the thermal exchange chamber includes at
least one second passage configured to direct
the cooling liquid out of the thermal
exchange chamber, the at least one second
passage is positioned at either the first end or
the second end of the thermal exchange
chamber.
Ex. 1001, 28:18–67.

II. ANALYSIS
A. CLAIM INTERPRETATION
We interpret claims in the same manner used in a civil action under
35 U.S.C. § 282(b), “including construing the claim in accordance with the
ordinary and customary meaning of such claim as understood by one of
ordinary skill in the art and the prosecution history pertaining to the patent.”
37 C.F.R. § 42.100(b) (2019).6 When applying that standard, we interpret

6 On October 11, 2018, the USPTO revised its rules to harmonize the
Board’s claim construction standard with that used in federal district court.
Changes to the Claim Construction Standard for Interpreting Claims in Trial
Proceedings Before the Patent Trial and Appeal Board, 83 Fed. Reg. 51,340
(Oct. 11, 2018) (now codified at 37 C.F.R. § 42.100(b) (2019)). This rule
change applies to petitions filed on or after November 13, 2018. Id.
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the claim language as it would be understood by one of ordinary skill in the
art in light of the specification. In re Suitco Surface, Inc., 603 F.3d 1255,
1260 (Fed. Cir. 2010). Thus, we give claim terms their ordinary and
customary meaning as they would be understood by an ordinarily skilled
artisan. See In re Translogic Tech., Inc., 504 F.3d 1249, 1257 (Fed. Cir.
2007) (“The ordinary and customary meaning ‘is the meaning that the term
would have to a person of ordinary skill in the art in question.’” (quoting
Phillips v. AWH Corp., 415 F.3d 1303, 1313 (Fed. Cir. 2005))). Only terms
that are in controversy need to be construed, and then only to the extent
necessary to resolve the controversy. Nidec Motor Corp. v. Zhongshan
Broad Ocean Motor Co., 868 F.3d 1013, 1017 (Fed. Cir. 2017).
In the Petition, Petitioner identifies “reservoir,” “chamber,”
“impeller,” “stator,” “heat radiator,” “an inlet positioned below the center of
the impeller,” and “intermediate member” as needing construction. Pet. 14–
20. Petitioner submits that the other terms do not require construction. Id. at
20. In its Preliminary Response, Patent Owner agreed with Petitioner’s
proposed constructions for “reservoir,” “chamber,” “impeller,” and “heat
radiator.” Prelim. Resp. 21. Patent Owner disagreed with Petitioner’s
constructions of “stator,” “intermediate member,” “an inlet positioned below
the center of the impeller,” “double-sided chassis,” and “a first end or a
second end of the thermal exchange chamber.” Id. at 21. In addition, Patent
Owner proposed a construction for “the pump chamber defined by an
intermediate and double-sided chassis housing.” Id. Patent Owner
submitted that, although it disputes Petitioner’s constructions of “stator,”
“intermediate member,” “double-sided chassis,” and “a first end or a second
end of the thermal exchange chamber,” no construction of these terms was
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necessary. Id. Patent Owner further submitted that resolving the parties’
conflicting constructions of the terms “an inlet positioned below the center
of the impeller” and “the pump chamber defined by an intermediate member
and a double-sided chassis housing” would aid our institution decision. Id.
In our Institution Decision, we agreed with Patent Owner that no
construction was necessary of “reservoir,” “chamber,” “impeller,” “heat
radiator,” “stator,” “intermediate member,” “double-sided chassis,” and “a
first end or a second end of the thermal exchange chamber” for our
determination of whether to institute inter partes review. Dec. 13. We also
agreed with the parties that resolving the constructions of “an inlet
positioned below the center of the impeller” and “the pump chamber defined
by an intermediate member and a double-sided chassis housing” would be
helpful for the Institution Decision. Id. at 13–14.
At this stage of the proceeding, the parties’ sole remaining claim
construction dispute centers on the claim phrase “an inlet positioned below
the center of the impeller,” which we consider below.
1. “an inlet positioned below the center of the impeller”
In the Petition, Petitioner submitted that the phrase “an inlet
positioned below the center of the impeller” should be construed as
including an “opening for fluid near the center of the impeller along the axis
around which the impeller rotates.” Pet. 16. In its Patent Owner Response,
Patent Owner argues that the phrase should be given its plain and ordinary
meaning. PO Resp. 8. In its Reply, Petitioner offers a new construction
(“New Construction”), and argues that we should instead construe the term
to mean “on the ‘cooling liquid’ side of the impeller’s center.” Reply 1–2.
In its Sur-Reply, Patent Owner argues that we should reject this new
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construction because it is untimely and incorrect. Sur-Reply 1–9. We agree
with Patent Owner that this phrase should receive its plain and ordinary
meaning.7
We begin with the claim language. The full limitation in claim 1
states “an inlet positioned below the center of the impeller configured to
enable the cooling liquid to flow into the center of the pump chamber.”
Ex. 1001, 28:50–53. Petitioner argues that the end portion of this
limitation—“configured to enable the cooling liquid to flow into the center
of the pump chamber”—supports its new construction that “below,” recited
earlier in the limitation, refers not to a direction, but instead to the cooling
liquid side of the apparatus. Reply 1–3. However, we agree with Patent
Owner that rather than support Petitioner’s construction, this language
suggests that Petitioner’s construction is not correct. Sur-Reply 4–5. As
Patent Owner explains, the claim already recites the functional relationship
between the inlet and the coolant; namely, the inlet is “configured to enable
the cooling liquid to flow into the center of the pump chamber.” Id.
Furthermore, the claim uses the word “below” in another limitation—“a
thermal exchange chamber formed below the pump chamber and vertically
spaced apart from the pump chamber.” Petitioner’s new construction would
require us to construe the term “below” differently in different limitations.
Moreover, consistent with Petitioner’s initial construction, we agree with
Patent Owner that the claim consistently uses “below” in a directional, not
functional sense. Thus, we agree with Patent Owner that the claim language

7 We also agree with Patent Owner’s argument that Petitioner’s new claim
construction is untimely. However, given that the issue is fully briefed and
discussed, we will consider it.
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does not support Petitioner’s new construction. See Epcon Gas Sys., Inc. v.
Bauer Compressors, Inc., 279 F.3d 1022, 1030–31 (Fed. Cir. 2002) (“A
word or phrase used consistently throughout a claim should be interpreted
consistently.” (quoting Phonometrics, Inc. v. Northern Telecom Inc., 133
F.3d 1459, 1465 (Fed. Cir. 1998))).
The written description does not compel departing from the ordinary
understanding of the word “below” as indicating a direction. As Patent
Owner explains, nothing in the written description supports reading “below”
as only describing a relationship with the cooling fluid side of the system.
Sur-Reply 6. Thus, the written description does not weigh in favor of the
construction.
Finally, Petitioner points to the testimony of Patent Owner’s expert
agreeing that the inlet is on the coolant liquid side of the apparatus. See
Reply 6 (citing Ex. 1012, 34:16–35:17). The fact that Petitioner’s new
construction is not inconsistent with the preferred embodiment does not
mean that this construction is correct. Instead, we find the claim language to
be clear on this point. Thus, we do not find the extrinsic evidence to compel
a particular construction. See Seabed Geosolutions (US) Inc. v. Magseis FF
LLC, --- F.4th ---, 2021 WL 3520472, at *3 (Fed. Cir. Aug. 11, 2021)
(“Given the clarity of the intrinsic evidence, resort to extrinsic evidence is
unnecessary.”)
In sum, we determine that the claim language is clear. The claim
already explicitly recites the functional relationship that with its new
construction Petitioner seeks to construe into the word “below.” We find the
better reading of claim 1’s usage of the term “below” to be in its ordinary
directional sense—as Petitioner originally proposed. Thus, we decline to
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adopt Petitioner’s new construction of “below,” and instead give this
limitation its plain and ordinary meaning.
We note, however, that Patent Owner additionally contends that “the
two limitations ‘a thermal exchange chamber formed below the pump
chamber’ and ‘an inlet positioned below the center of the impeller’ together
impose a positional requirement for the term ‘below’ which must be applied
consistently to both limitations.” PO Resp. 19. We begin again with the
language of claim 1. Claim 1 recites that the “thermal exchange chamber” is
“formed below the pump chamber and vertically spaced apart from the pump
chamber,” and that the “heat radiator” is “positioned at a location
horizontally spaced apart from the heat generating component.” Thus,
claim 1 contains “vertical” or “horizontal” references in addition to a
requirement that the “thermal exchange chamber” be “below” the “pump
chamber.” We find that the combination of this language suggests a specific
frame of reference for the components of the claimed system.8
Petitioner argues that Patent Owner is attempting to read the limitation
“vertically” into the term “below,” and that this would render claim 1’s
recitation of “vertically spaced apart” superfluous. Reply 9. However, we
agree with Patent Owner that it is not seeking to read the limitation

8 The language of disclaimed claim 8, in contrast to the language of claim 1,
does not impose any specific particular positional/directional frame of
reference on the entire claimed cooling device, which indicates that Patent
Owner knew how to claim a device with multiple frames of reference. See
Intellectual Ventures I LLC v. T-Mobile USA, Inc., 902 F.3d 1372, 1379
(Fed. Cir. 2018) (“This shows that the patentee knew how to restrict the
resource allocator to using information obtained from layer 7. If the
patentee had intended to similarly restrict the resource allocator in claim 1, it
could have done so using the language of claim 19, but did not.”).
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“vertically” into term “below.” The frame of reference of the claims comes
from the other limitations in claim 1, which directionally orient the thermal
exchange chamber, pump chamber, and heat exchanger. Sur-Reply 9–10.
We agree with Patent Owner that its arguments arise not from importing a
limitation into “below,” but instead from applying the ordinary meaning of
“below” once that positional frame of reference in the claim is established.
See id.
On this point of whether Patent Owner is reading limitations into
“below,” Petitioner relies heavily on testimony of Patent Owner’s expert,
Dr. Tilton, where Dr. Tilton characterizes “vertically spaced apart” as
seeming “superfluous” to him. Reply 10–11 (citing Ex. 1012, 27:19–28:1,
34:16–35:17). However, we agree with Patent Owner that when this
testimony is read in context, Dr. Tilton clarifies that “vertically spaced
apart” is not “completely redundant,” Ex. 1012, 28:24–29:9, because two
things “could also be below and horizontally spaced apart, . . . meaning it
would be below it, but off to the side,” id. at 27:6–11. Thus, when read in
context, we do not agree with Petitioner’s characterization of Dr. Tilton’s
overall testimony as reading a limitation into “below.” Moreover, given the
clear and simple claim language, we do not find either parties’ extrinsic
evidence to be helpful in resolving this dispute.
We further note that the Specification is consistent with this
construction. Figures 17 and 20 and the supporting discussion are consistent
with understanding the claim language as imposing an express limitation of
the positional/directional frame in claim 1. The embodiment shown in
Figures 17 and 20 of the ’681 patent shows a device with an inlet “below”
the center of the impeller and a consistent positional frame of reference for
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the entire device. “[W]hile it is of course improper to limit the claims to the
particular preferred embodiments described in the specification, the
patentee’s choice of preferred embodiments can shed light on the intended
scope of the claims.” Astrazeneca AB v. Mut. Pharm. Co., 384 F.3d 1333,
1340 (Fed. Cir. 2004).
Accordingly, we determine that “an inlet positioned below the center
of the impeller” should be given its plain and ordinary meaning. We further
determine that Patent Owner is correct that claim 1 does have a particular
positional/directional frame of reference that is used throughout the claim.
2. Other Claim Terms
We discern no other terms in need of express interpretation.
Accordingly, we apply the legal standards set forth above when reading the
claims.
B. THE PARTIES’ POST-INSTITUTION ARGUMENTS
In our Institution Decision, we concluded that the argument and
evidence adduced by Petitioner demonstrated a reasonable likelihood that
claims 8, 11, 15, and 16, which have now been disclaimed, were
unpatentable. Dec. 31–32. We noted that Petitioner had not shown a
reasonable likelihood that claims 1 and 4 were unpatentable (id.), but we
instituted on those claims under governing precedent and guidance. See SAS
Inst., Inc. v. Iancu, 138 S. Ct. 1348, 1354, 1359–60 (2018); see also PGS
Geophysical AS v. Iancu, 891 F.3d 1354, 1360 (Fed. Cir. 2018) (interpreting
the statute to require “a simple yes-or-no institution choice respecting a
petition, embracing all challenges included in the petition”); Consolidated
Trial Practice Guide 64 (Nov. 2019), https://www.uspto.gov/TrialPractice
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GuideConsolidated (“Consolidated TPG”) (“The Board will not institute on
fewer than all claims or all challenges in a petition.”).
We must now determine whether Petitioner has established by a
preponderance of the evidence that the remaining challenged claims are
unpatentable over the cited prior art. 35 U.S.C. § 316(e) (2018). We
previously instructed Patent Owner that “any arguments not raised in the
[Patent Owner Response] may be deemed waived.” Paper 10, 8; see also In
re NuVasive, Inc., 842 F.3d 1376, 1381 (Fed. Cir. 2016) (holding that patent
owner’s failure to proffer argument at trial as instructed in scheduling order
constitutes waiver). Additionally, the Board’s Trial Practice Guide states
that the Patent Owner Response “should identify all the involved claims that
are believed to be patentable and state the basis for that belief.”
Consolidated TPG at 66.
C. LEGAL STANDARDS
Petitioner challenges the patentability of claims 1 and 4 on the ground
that the claims are unpatentable as obvious over Duan, Shin, and Cheon. To
prevail in its challenge to the patentability of the claims, Petitioner must
establish unpatentability by a preponderance of the evidence. 35 U.S.C.
§ 316(e); 37 C.F.R. § 42.1(d) (2019). “In an [inter partes review], the
petitioner has the burden from the onset to show with particularity why the
patent it challenges is unpatentable.” Harmonic Inc. v. Avid Tech., Inc., 815
F.3d 1356, 1363 (Fed. Cir. 2016) (citing 35 U.S.C. § 312(a)(3) (requiring
inter partes review petitions to identify “with particularity . . . the evidence
that supports the grounds for the challenge to each claim”)). This burden
never shifts to Patent Owner. See Dynamic Drinkware, LLC v. Nat’l
Graphics, Inc., 800 F.3d 1375, 1378 (Fed. Cir. 2015) (citing Tech. Licensing
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Corp. v. Videotek, Inc., 545 F.3d 1316, 1326–27 (Fed. Cir. 2008))
(discussing the burdens of proof in inter partes review).
The Supreme Court in KSR International Co. v. Teleflex Inc., 550
U.S. 398 (2007), reaffirmed the framework for determining obviousness as
set forth in Graham v. John Deere Co., 383 U.S. 1 (1966). The KSR Court
summarized the four factual inquiries set forth in Graham that we apply in
determining whether a claim is unpatentable as obvious under 35 U.S.C.
§ 103(a) as follows: (1) determining the scope and content of the prior art,
(2) ascertaining the differences between the prior art and the claims at issue,
(3) resolving the level of ordinary skill in the pertinent art, and (4) when in
evidence, considering objective evidence indicating obviousness or
nonobviousness. KSR, 550 U.S. at 406 (citing Graham, 383 U.S. at 17–18).
In an inter partes review, Petitioner cannot satisfy its burden of proving
obviousness by employing “mere conclusory statements.” In re Magnum
Oil Tools Int’l, Ltd., 829 F.3d 1364, 1380 (Fed. Cir. 2016).
Petitioner must explain how the proposed combinations of prior art
would have rendered the challenged claims unpatentable. An obviousness
analysis “need not seek out precise teachings directed to the specific subject
matter of the challenged claim, for a court can take account of the inferences
and creative steps that a person of ordinary skill in the art would employ.”
KSR, 550 U.S. at 418; accord Translogic, 504 F.3d at 1259. Petitioner also
must articulate a reason why a person of ordinary skill in the art would have
combined the prior art references. NuVasive, 842 F.3d at 1382.
At this final stage of the proceeding, we determine whether a
preponderance of the evidence of record shows that the remaining
challenged claims would have been rendered obvious in view of the asserted
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prior art. We analyze the asserted ground of unpatentability in accordance
with these principles.
D. LEVEL OF ORDINARY SKILL
We review the grounds of unpatentability in view of the
understanding of a person of ordinary skill in the art at the time of the
invention. Graham, 383 U.S. at 17. Petitioner proposes that a person of
ordinary skill
would have been knowledgeable regarding liquid cooling
systems for computer systems, would have earned at least a
bachelor’s degree, such as an B.S. (bachelor of science), or
equivalent thereof, in electrical or mechanical engineering or a
closely-related field, and would have possessed at least two or
three years of experience in liquid cooling systems for computer
systems, or in similar systems.
Pet. 4 (citing Ex. 1003 ¶¶ 25–30). Patent Owner does not dispute this
definition of a person of ordinary skill. See generally PO Resp. Patent
Owner’s expert, Dr. Tilton, however, testifies that
A person having ordinary skill in the field of liquid cooling
systems at that time (i.e., in May 2005) would have (i) completed
college level course work in thermodynamics, fluid mechanics,
and heat transfer, and (ii) attained two or more years of
experience in designing liquid cooling systems for computers,
servers, or other electronic devices, or very similar technology.
Alternatively, a person with a more advanced degree in the above
fields may have had less practical experience and be a person of
ordinary skill in the art.
Ex. 2018 ¶ 23.
We see no meaningful distinction between these definitions relevant
to the particular issues necessary to decide this case. We adopt Petitioner’s
proposed level of ordinary skill, as it appears to be consistent with the level
of skill reflected by the Specification and in the asserted prior art references.
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See Okajima v. Bourdeau, 261 F.3d 1350, 1355 (Fed. Cir. 2001) (the prior
art itself can reflect the appropriate level of ordinary skill in the art).

E. CLAIMS 1, 4:
OBVIOUSNESS BASED ON DUAN, SHIN, CHEON
Petitioner argues that the combination of Duan, Shin, and Cheon
renders claims 1 and 4 unpatentable as obvious. Pet. 26–68. Claim 1 is
independent and claim 4 depends from claim 1. Ex. 1001, 28:18–67, 29:10–
14. Patent Owner argues that, given the positional frame of reference of the
claim, Petitioner’s challenge to claims 1 and 4 fails. See PO Resp. 15–21.
We have agreed with Patent Owner’s proposed construction and agree with
its effect on Petitioner’s challenge. Accordingly, as explained below, we
determine that Petitioner has not proven by a preponderance of evidence that
the combination of Duan, Shin, and Cheon renders claims 1 and 4
unpatentable as obvious.
1. Independent Claim 1
We first consider Petitioner’s argument that the combination of Duan,
Shin, and Cheon renders obvious claim 1. Pet. 26–64.
a. Duan
Duan is titled “Cooling Plate Module.” Ex. 1005, at [54]. Duan
discloses a cooling plate module for cooling a CPU. Id. ¶ 2. Duan’s system
includes a cooling plate module with a cooling plate integrally formed with a
liquid driving module such that the layout of the cooling plate module can be
minimized to reduce space. Id. ¶ 7. Figure 6, reproduced below, is a view
of the liquid cooling cyclic mechanism of Duan. Id. ¶ 17.
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Figure 6, reproduced above, shows liquid cooling cyclic mechanism
100 for cooling CPU 200. Id. ¶ 22. Liquid cooling cyclic mechanism 100
consists of cooling module 10 and water tank module 20, which is connected
with cooling plate module 10 through ducts. Id. Cooling plate module 10
includes cooling plate 1, liquid driving module 2, and heat absorbing
interface 11. Id. Heat absorbing face 11 is in contact with CPU 200 for
dissipating heat generated by CPU 200. Id. ¶ 26.
Water tank 20 includes box 5, with liquid entrance region 51 and
liquid exit region 52 on either side of box 5 and cooling stage 53 in the
center of box 5. Id. ¶ 25. Cooling stage 53 has a plurality of heat-
dissipating fins 531 arranged in rows with runners 532 defined between rows
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of heat dissipating fins 531. Id. When hot liquid in liquid entrance region
51 flows to liquid exit region 52, heat from the hot liquid dissipates through
heat-dissipating fins 531 and the resulting cool liquid flows to liquid exit
region 52. Id.
Liquid inlet 23 of cooling plate module 10 is connected to liquid
outlet 521 of liquid exit region 52 of water tank 20 through duct 6. Id.
Second liquid outlet 31 of cooling plate module 10 is connected to liquid
inlet 511 of liquid entrance region 51 of water tank 20 through duct 6, which
allows hot liquid from cooling plate module 10 to be cooled and cycled back
to cooling plate module 10. Id.
Figure 2, reproduced below, is an exploded view of cooling plate
module 10 of Duan. Id. ¶ 13.

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Figure 2, reproduced above, shows a detailed exploded view of
cooling plate module 10. Liquid driving module 2 of cooling plate module
10 includes accommodation chamber 21 and liquid driving unit 22 located in
accommodation chamber 21 to drive the cool liquid. Id. ¶ 23. Liquid
driving unit 22 includes coil stage 221, upper cover 222, impeller stage 223,
sealing washer 224, and lower cover 225. Id. Lower cover 225 includes
liquid inlet 23 connected with accommodation chamber 21. Id. First liquid
outlet 24 connects to the bottom of accommodation chamber 21 and is
enclosed by cap 3. Id. Cap 3 includes second liquid outlet 31, cooling plate
1 is assembled with cap 3 to define a closed space therein, and first liquid
outlet 24 is corresponding to heat-dissipating plates 12. Id. Duan explains
that liquid driving module 2 can be a reciprocating pump, centrifugal pump,
or axial-flow pump. Id.
Figure 7 of Duan, reproduced below, is a sectional view of the cooling
plate module. Id. ¶ 18.

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Figure 7, reproduced above, is a sectional view of the cooling plate
module of Duan. As shown in Figure 7, the cool liquid in water tank 20
flows to accommodation chamber 21 through duct 6 and liquid inlet 23 of
cooling plate module 10 and is driven by liquid driving unit 22. Id. ¶ 27.
The cool liquid then flows to cap 3 through first liquid outlet 24 for heat
dissipating heat-dissipating plates 12 in cap 3. Id. The cool liquid is then
heat exchanged with heat-dissipating plates 12 into hot liquid. Id. The hot
liquid then flows to liquid entrance region 51 of water tank 20 through
second liquid outlet 31 of cooling plate module 10 and another duct 6.
b. Shin
Shin is titled “Cooling device for electronic equipment.” Ex. 1006, at
[54]. Shin discloses “a cooling structure for liquid cooling of heat
generating electronic circuit components such as LSI chips installed on a
wiring board, relating in particular to a cooling structure for compactly
mounting a liquid cooled heat sink and pump.” Id. ¶ 1. Shin teaches that
“[u]sing a DC motor allows the motor speed to be easily changed by
changing the DC voltage, thus enabling control of cooling power.
Moreover, making the motor into a DC brushless motor makes it possible to
implement a pump of low noise and long service life.” Id. ¶ 19. Shin also
teaches the following:
Besides the heat generating element 1, heat generating elements
22a, 22b, 22c, such as memory LSI and driver LSI chips, which
can be cooled by air cooling, as well as an IO card, memory card,
hard disk or other card mounting board 23 are also installed on
the wiring board 2. The wiring board 2 is housed inside case 24,
which is an electronic equipment case. An air cooling fan 34 is
installed in the case 24, and the aforementioned multiple air
cooled components are air-cooled by cooling air 25.
Id. ¶¶ 23, 24.
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c. Cheon
Cheon is titled “Cooling System for Computer.” Ex. 1007, at [54].
Cheon discloses a cooling system for a computer having a heat transfer
device contacting a computer component and communicating with a liquid
coolant reservoir via first and second conduits, a radiator mounted on the
outside of the computer housing and in heat exchanging contact with the
reservoir, and a pump and brushless motor therefor mounted on the reservoir
casing. Id. at 1:5–12. Specifically, Cheon discloses such a cooling system
that has a control circuit that controls circulation of coolant based on
feedback from one or more sensors indicating the temperatures of the
components attached to the heat transfer device. Id. at 5:66–6:16.
d. Analysis
Patent Owner argues that Petitioner fails to prove the unpatentability
of claim 1 because Duan fails to disclose both an “inlet” and a “thermal
exchange chamber” that are positioned below the “pump chamber.” PO
Resp. 1. We agree.
In the Petition, Petitioner argues that Duan accounts for the limitation
“an inlet positioned below the center of the impeller configured to enable the
cooling liquid to flow into the center of the pump chamber.” See Pet. 51–53.
Petitioner submits that “Duan discloses an inlet (e.g., an opening below the
impeller that receives liquid from liquid inlet 23) positioned below the center
of the impeller (e.g., impeller stage 223) configured to enable the cooling
liquid to flow into the center of the pump chamber (e.g., accommodation
chamber 21 and lower cover 225).” Id. at 51. Petitioner provides a side-by-
side annotated comparison of Figure 7 of Duan and Figure 20 of the ’681
patent, which is reproduced below.
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Petitioner’s illustration is an annotated side-by-side comparison of
Figure 7 of Duan and Figure 20 of the ’681 patent with a red box identifying
the portion of each device, which Petitioner identifies as the “inlet below the
center of the impeller.” Pet. 52.
With respect to the limitation of claim 1 of “a thermal exchange
chamber formed below the pump chamber and vertically spaced apart from
the pump chamber, the pump chamber and the thermal exchange chamber
being separate enclosed chambers that are fluidly coupled,” Petitioner relies
exclusively on Duan and offers the following annotated version of Figure 8
of Duan to support its analysis.
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Petitioner’s illustration shows Figure 8 of Duan, as annotated by
Petitioner showing a red box around the upper part of the device, which
Petitioner identifies as the “pump chamber” and a blue box around the
bottom portion of the device, which Petitioner identifies as the “thermal
exchange chamber.” Pet. 35. Petitioner submits that the thermal exchange
chamber is shown in the blue box of this annotated version of Figure 8 and
the pump chamber is shown in the red box. Id. Petitioner further submits
that the chamber is vertically spaced apart as required by the claim. Id. at
35–36.
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As explained above in the claim construction section, claim 1 requires
a single frame of reference throughout the claim. See supra II.A.1. Given
this requirement, we determine that Petitioner has failed to establish by a
preponderance of the evidence that Duan accounts for both “an inlet
positioned below the center of the impeller configured to enable the cooling
liquid to flow into the center of the pump chamber” and “a thermal exchange
chamber formed below the pump chamber and vertically spaced apart from
the pump chamber, the pump chamber and the thermal exchange chamber
being separate enclosed chambers that are fluidly coupled.” Patent Owner’s
expert and Petitioner’s expert both agree that when a consistent frame of
reference is applied, Duan cannot teach both of these limitations. See
Ex. 2018 ¶ 40; see also Ex. 2016, 40:3–44:2, 47:6–49:14 (Petitioner’s expert
agreeing that if a single directional frame of reference is applied to all
features in Duan’s cooling device, then Duan does not teach both these
limitations). Accordingly, we agree with the expert’s testimony and
determine that Duan does not account for the limitations of claim 1, as
properly construed.
e. Conclusion
Based on our review of Petitioner’s argument and evidence of record,
and for all the reasons expressed above, we conclude that Petitioner has not
established by a preponderance of evidence that claim 1 is unpatentable as
obvious over Duan, Shin, and Cheon.

2. Dependent Claim 4
Claim 4 depends from claim 1. Petitioner provides no additional
evidence or argument as to why claim 4 should be treated differently than
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claim 1 regarding the directional limitations in claim 1. Because we have
determined that Petitioner has failed to show by a preponderance of the
evidence that claim 1 is unpatentable as obvious over Duan, Shin, and
Cheon, we also determine that Petitioner has failed to show by a
preponderance of the evidence that claim 4 is unpatentable over Duan, Shin,
and Cheon.

3. Summary
For all the reasons expressed above, we conclude that Petitioner has
failed to establish by a preponderance of evidence that the combination of
Duan, Shin, and Cheon renders claims 1 and 4 unpatentable as obvious
under § 103(a).
III. CONCLUSION
In summary,
Claim(s)
35
U.S.C. § Reference(s)
Claim(s)
Shown
Unpatentable
Claim(s) Not
Shown
Unpatentable
1, 4 103 Duan, Shin, Cheon 1, 4
Overall Outcome 1, 4
IV. ORDER
For the reasons given, it is:
ORDERED that Petitioner has not shown based on a preponderance of
evidence that claims 1 and 4 of U.S. Patent No. 9,399,531 B2 are
unpatentable; and
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FURTHER ORDERED because this is a final written decision, the
parties to this proceeding seeking judicial review of our Decision must
comply with the notice and service requirements of 37 C.F.R. § 90.2.

For PETITIONER:
Heath Briggs
GREENBERG TRAURIG, LLP
briggsh@gtlaw.com

For PATENT OWNER:

Eric Raciti
Arpita Bhattacharyya
FINNEGAN, HENDERSON, FARABOW, GARRETT & DUNNER, LLP
eric.raciti@finnegan.com
arpita.bhattacharyya@finnegan.com