ICEOTOPE LIMITED

Patent Trials and Appeals Board

May 3, 2021

2020005945 (P.T.A.B. May. 3, 2021)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
15/416,854 01/26/2017 Daniel CHESTER 030310-000140US 1086
12075 7590 05/03/2021
Butzel Long
1909 K St. NW
Suite 500
Washington, DC 20006
EXAMINER
STCLAIR, ANDREW D
ART UNIT PAPER NUMBER
3799
NOTIFICATION DATE DELIVERY MODE
05/03/2021 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
docket@butzel.com
kamlay@butzel.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte DANIEL CHESTER, PETER HOPTON,
JASON BENT, and KEITH DEAKIN
Appeal 2020-005945
Application 15/416,854
Technology Center 3700
Before JILL D. HILL, CARL M. DEFRANCO, and LEE L. STEPINA,
Administrative Patent Judges.

DEFRANCO, Administrative Patent Judge.
DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision in the Final Office Action rejecting claims 1–20. We
have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM.
CLAIMED SUBJECT MATTER
Appellant’s claimed invention relates to a cooling system for heat-
generating electronic components, such as “computer processors and

1 We use the term “Appellant” to refer to “applicant” as defined in 37 C.F.R.
§ 1.42(a). Appellant identifies the real party in interest as Iceotope Group
Limited. Appeal Br. 1.
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motherboards.” Spec. 1:10–17. Claim 1, which is illustrative of the claimed
subject matter, recites:
1. A cooled electronic system, comprising:
a sealed container comprising: a housing; and an
electronic device immersed in a primary cooling liquid; and
a first heat transfer device for receiving a secondary
cooling liquid, the first heat transfer device being configured to
transfer heat between the primary cooling liquid and the
secondary cooling liquid;
wherein the cooled electronic system is configured to
control a flow rate of the secondary cooling liquid so as to
cause the temperature of the electronic device not to exceed a
predetermined maximum operating temperature and such that
the primary cooling liquid and the secondary cooling liquid are
maintained in a liquid state; and
wherein the primary cooling liquid is selected so that,
when the cooled electronic system is in operation, heat
generated by the electronic device is transferred to the primary
cooling liquid initially via local conduction and, subsequently
upon expansion of the primary cooling liquid, heat generated by
the electronic device is transferred to the primary cooling liquid
via convection.
Appeal Br. 9 (Claims App.).
EXAMINER’S REJECTIONS
1. Claims 1–6, 9–16, 19, and 20 stand rejected under 35 U.S.C.
§ 103(a) as unpatentable over Campbell (US 2010/0101759 A1, pub.
Apr. 29, 2010), Larson (US 5,485,671, iss. Jan. 23, 1996), and Santiago (US
2003/0085024 A1, pub. May 8, 2003). Final Act. 4–9.
2. Claims 7, 8, 17, and 18 stand rejected under 35 U.S.C. § 103(a) as
unpatentable over Campbell, Larson, Santiago, and Teneketges (US
2006/0002086 A1, pub. Jan. 5, 2006). Final Act. 10–11.
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3. Claims 9 and 19 stand rejected under 35 U.S.C. § 112, first
paragraph, as lacking written description support. Final Act. 3–4.
ANALYSIS
A. Obviousness (Claims 1–20)
Appellant argues all the claims together, noting that independent
claims 1 and 12 recites similar limitations and that the dependent claims are
patentable for “the same reasons” as the independent claims. Appeal Br. 7.
Thus, we select claim 1 as representative, with the remaining claims
standing or falling therewith. See 37 C.F.R. § 41.379(c)(1)(iv).
The Examiner finds that Campbell discloses a cooling system
substantially as claimed, but fails to disclose that the primary and secondary
cooling liquids “are maintained in a liquid state.” Final Act. 5. Although
Campbell’s first coolant indisputably remains in a liquid state, the Examiner
acknowledges that “the second coolant is a phase-change coolant,” meaning
that it changes from a vapor to a liquid at some point in the heat exchange
process. Id. (citing Campbell ¶ 27) (emphasis added). For that missing
feature, the Examiner takes two approaches.
First, the Examiner finds that Appellant’s failure to traverse the
Examiner’s previously-stated “official notice” amounts to an admission of
fact that single-phase and two-phase heat exchanger systems “are known in
the prior art as alternatives.” Final Act. 5 (citing MPEP 2144.039(C)).
Alternatively, the Examiner points to Campbell for teaching that single-
phase and two-phase systems are well-known, and Larson for teaching that
these systems are known alternatives for cooling heat-generating electronic
components despite disadvantages associated with each type of system. See
id. at 5–6 (citing Campbell ¶ 27; Larson, 2:12–3:64). Based on those
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teachings, the Examiner surmises that a skilled artisan would have known
how to modify Campbell’s second two-phase coolant circuit into a single-
phase coolant circuit as a matter of routine selection with known design
considerations and “doing so would merely amount to a simple substitution
of one known element for another with predictable results.”2 Id. at 6; see
also Ans. 3.
To begin, Appellant disputes the Examiner’s taking of official notice
that single-phase and two-phase heat exchanger systems are known
alternatives. Appeal Br. 4. Contrary to the Examiner’s assertion that “this
fact has not been traversed and is now admitted prior art” (Final Act. 5),
Appellant argues that it has “repeatedly disputed the accuracy and relevance
of such a finding.” Id. We agree with Appellant. The Examiner
misrepresents the record. From our review, the Examiner first took “official
notice” of the interchangeability of single-phase and two-phase systems in
an office action dated January 8, 2018. Appellant, in a timely response,
traversed the Examiner’s assertion, as indicated by the following statement:
Regarding the Office Action’s taking of official notice that
“single-phase and two-phase heat exchange systems are known
in the prior art as alternatives with different design
considerations and disadvantages,” Applicant respectfully
requests that the Examiner provide evidence that such systems
are known to be “simple substitutions” for each other “to

2 The Examiner also finds that Santiago teaches the claim limitation that the
system controls a flow rate of the secondary coolant liquid so as to regulate
the temperature within a predefined limit and that a skilled artisan would
have known to do this “for the purpose of protecting the computer from
temperature damage and/or ensure optimum.” Final Act. 6. Appellant does
not dispute this finding. See Appeal Br. 3–5. Not being apprised of error
with this aspect of the Examiner’s rejection, we need not address it further.
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obtain predictable results,” as would be necessary for this taking
of official notice . . . .
Amendment After Final (dated Mar. 26, 2018), at 12.
And that was not the only time Appellant traversed the Examiner’s
taking of official notice. For instance, in responding to a renewed assertion
by the Examiner of official notice, Appellant again states unequivocally that
it “respectfully disagrees” with that assertion and proceeds to explain why.
Compare Non-Final Act (dated Mar. 20, 2019), at 6, with Amendment
(dated July 22, 2019), at 13–14. Thus, the Examiner’s position that the
“taking of official notice was not traversed” strains credulity. Ans. 3. As
such, we see clear error in the Examiner’s finding that the noticed facts were
admitted by Appellant.
We turn now to the Examiner’s finding that the references themselves
nonetheless teach that single-phase and two-phase heat exchanger systems
are known alternatives. See Final Act. 5–6; see also Ans. 4–5
(“Additionally, even if it is determined that the admitted prior art should not
be considered, the additional evidence in the record is sufficient to support
the finding that single-phase and two-phase coolant systems are well
known.”). Appellant disputes that finding by submitting an “expert
declaration” purporting to show that “Campbell’s cooling system would
have to be entirely redesigned in order to use coolants that are ‘maintained
in a liquid state’ as recited in independent claim 1.” Appeal Br. 3–4
(emphasis added). In support, Appellant submits an “expert declaration”
from one of its employees, declaring:
A single-phase (liquid) coolant would not work in [Campbell’s]
system. The Campbell system relies on the vapor pressure to
create a thermal syphon around the system. The vapor or gas
expands, thereby causing a rise in pressure. The vapor will be
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forced along the upper flexible tubing 244 into the chassis level
manifold 240. If the coolant remained in a single phase, there
would be some circulation due to convection flows caused by the
raising and lowering in temperature. However, this would create
local convection flows and eddies. Most likely there would be
localized convection below the baffle 213 and above the baffle
213. This would not force coolant along the upper flexible tubing
244 into the chassis level manifold 240 and “heat transfer
device”, thereby preventing heat transfer in Campbell’s system.
Therefore, I would not expect Campbell’s system to operate
properly and provide adequate cooling if a single-phase coolant
was used as the second coolant.
Appellant’s Declaration under 37 C.F.R. § 1.132 (dated July 19, 2019) ¶ 8
(emphases added).
Neither Appellant’s arguments nor its expert declaration persuades us
of error in the Examiner’s rationale for combining the teachings of the
asserted references. That is because they do not accurately reflect the
proposed modification of Campbell put forth by the Examiner. More
specifically, Appellant’s arguments and declaration merely address what
would happen if a single-phase coolant alone was incorporated into
Campbell’s system. But the Examiner does not propose to merely
incorporate a single phase coolant into the two-phase cooling circuit of
Campbell, which necessarily requires condensation and evaporation of the
coolant. Instead, the Examiner’s proposed modification includes replacing
the entire two-phase coolant circuit of Campbell’s system with a single-
phase coolant circuit as taught by Larson. Thus, even accepting the facts in
Appellant’s declaration as true, it fails to account for how the Examiner
actually proposes to modify Campbell’s system. As such, we are not
apprised of error in the Examiner’s rationale for combining the teachings of
Campbell, Larson, and Santiago.
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Appellant’s remaining argument centers on the assertion that the
Examiner’s proposed modification “would cause a significant change to the
principle of operation” of Campbell’s system. Appeal Br. 4–5. According
to Appellant, “Larson as relied upon by the Examiner also demonstrates that
it would require a significant change to the principle of operation of
Campbell's system to make the proposed modifications, in order to account
for the very different disadvantages and needs of the two types of systems.”
Id. at 5.
We disagree. As the Examiner correctly explains, the principle of
operation of Campbell’s system is to cool an electronic subsystem, such as a
processor module, without relying on air-moving devices such as fans or
blowers. See Campbell ¶¶ 3, 7. Contrary to Appellant’s argument,
Campbell is not focused exclusively on the goal of causing a phase change
in a liquid-coolant, but rather highlights more generally that “liquid cooling
of selected components is an attractive technology to manage the higher heat
fluxes” of microprocessors. See id. ¶ 4. As such, Campbell begins by
describing its cooling system in more general terms of “any heat exchange
assembly through which a first coolant and a second coolant can circulate.”
Id. ¶ 27. Construing the principle of operation of Campbell’s system so
narrowly as to require every aspect of the disclosed exemplary embodiment
would effectively nullify the obviousness inquiry of how a skilled artisan
would have understood the reference as whole. See KSR Int’l Co. v. Teleflex
Inc., 550 U.S. 398, 420–21 (2007) (a skilled artisan has “ordinary creativity”
and is not an “automaton”). And, in any event, Larson indicates that a
single-phase technique entails a simpler operation where the coolant
“remains in the liquid phase over the normal and expected system operating
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temperature,” as opposed to the more complex operation of a two-phase
technique where the coolant “changes from the liquid phase to the vapor
phase during at least one point in the normal operating temperature range”
before “travel[ing] to a condenser section of the system, where the coolant
vapor is converted back into a liquid . . . [and] returned by some means to
the heat dissipating component.” Larson, 2:12–22, 2:64–3:5.
In sum, we discern no error in the Examiner’s reasoning for
combining the teachings of Campbell, Larson, and Santiago. Rather,
because the Examiner provides sufficient reasoning with rational
underpinning for why a skilled artisan would choose to replace Campbell’s
two-phase circuit for the second coolant with a single-phase circuit,
including all necessary modifications involved in that choice, we sustain the
rejection of claim 1 as obvious over the combined teachings of Campbell,
Larson, and Santiago. And because Appellant does not argue claims 2–20
separately from claim 1, we likewise sustain the Examiner’s rejection of
those claims. See Appeal Br. 7.
B. Lack of Written Description Under 35 U.S.C. 112
Appellant’s argument challenging the Examiner’s written description
rejection is based on the misperception that dependent claims 9 and 19
“were submitted in their current form with the initial filing of the present
application,” in other words, that they are original claims. Appeal Br. 7.
However, according to the Examiner, “claims 9 and 19 were added via
[Appellant’s] amendment of September 28, 2017, which was filed after the
Non-Final Rejection of August 31, 2017.” Ans. 6. Appellant neither
disputes that contention, nor otherwise points us to any portion of the
Specification in support of dependent claims 9 and 19. See Appeal Br. 7–8;
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Reply Br. 1–4. Because Appellant does not apprise us of error in the
Examiner’s finding that claims 9 and 19 do not benefit from the presumption
of an adequate written description typically accorded original claims, we
sustain the Examiner’s rejection of claims 9 and 19 under 35 U.S.C. § 112,
first paragraph.
CONCLUSION
Claim(s)
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
1–6, 9–16,
19, 20
103(a) Campbell, Larson,
Santiago
1–6, 9–16,
19, 20

7, 8, 17,
18
103(a) Campbell, Larson,
Santiago, Teneketges
7, 8, 17,
18

9, 19 112 Written Description 9, 19
Overall
Outcome
1–20

TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv).

AFFIRMED