Waters Technologies Corporation

Patent Trials and Appeals Board

Jun 24, 2021

2020002905 (P.T.A.B. Jun. 24, 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.
15/909,258 03/01/2018 Michael O. Fogwill W-2760-US2 6652
13871 7590 06/24/2021
WOMBLE BOND DICKINSON (US) LLP / Waters
ATTN: IP DOCKETING
P.O. BOX 7037
ATLANTA, GA 30357-0037
EXAMINER
OLAMIT, JUSTIN N
ART UNIT PAPER NUMBER
2853
NOTIFICATION DATE DELIVERY MODE
06/24/2021 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):
BostonDocket@wbd-us.com
IPDocketing@wbd-us.com
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte MICHAEL O. FOGWILL and JOSHUA A. SHREVE

Appeal 2020-002905
Application 15/909,258
Technology Center 2800
____________

Before DONNA M. PRAISS, MICHELLE N. ANKENBRAND, and
JANE E. INGLESE, Administrative Patent Judges.

PRAISS, Administrative Patent Judge.

DECISION ON APPEAL1

Pursuant to 35 U.S.C. § 134(a), Appellant2 appeals from the
Examiner’s decision to reject claims 1, 3–10, and 12–20, which constitute all
the claims pending in this application. We have jurisdiction under
35 U.S.C. § 6(b).
We AFFIRM.

1 In this Decision, we refer to the Specification filed Mar. 1, 2018 (“Spec.”),
the Final Office Action dated June 6, 2019 (“Final Act.”), the Appeal Brief
filed Oct. 31, 2019 (“Appeal Br.”), the Examiner’s Answer dated Jan. 10,
2020 (“Ans.”), and the Reply Brief filed Mar. 9, 2020 (“Reply Br.”).
2 We use the word “Appellant” to refer to “applicant” as defined in
37 C.F.R. § 1.42. Appellant identifies Waters Technologies Corporation as
the real party in interest. Appeal Br. 2.
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STATEMENT OF THE CASE
The invention relates to controlling pressure in carbon dioxide-based
chromatography systems. Spec. 1:9–10. Appellant’s Figure 3 is shown
below.

Figure 3 above depicts CO2 pump 303 upstream from column 315, back
pressure regulator (BPR) 321 downstream from the column, secondary
pressure control 327 downstream from the BPR, and detector 323
downstream from the secondary pressure control. Appeal Br. 4; Spec. 7:16–
8:5.
According to the Specification, BPRs are used in known CO2-based
chromatography systems downstream from the column and upstream of a
detector. Spec. 6:11–20. The length of tubing used between the BPR outlet
and detector can be challenging, however, because the BPR is of a
considerable size and is an appreciable distance from the detector, so the
system requires a post-column addition pump or makeup fluid pump to aid
in transporting analyte through the post-BPR tubing. Spec. 6:21–27.
Alternately, known CO2-based chromatography systems use a split-flow to
split off the detector at a point upstream from the BPR with proper restrictor
design to address the challenges encountered when interfacing a system with
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a BPR to a low-pressure detector. Id. at 7:5–15. The Specification describes
disadvantages of the split-flow design including (1) proportionally lower
sensitivity with the split-flow design due to only a portion of the analyte
being introduced to the detector, and (2) changes in the system pressure due
to the use of a fixed restrictor can result in a change in the split ratio
interfering with quantitation. Id. at 7:11–15.
Independent claims 1 and 18, reproduced below, are illustrative of the
subject matter on appeal (emphasis added).
1. A system of controlling pressure of a mobile phase, the
system comprising:
a pump for pumping a mobile phase including CO2, the
pump located upstream of a chromatography column;
a primary pressure control element located downstream
of the column and disposed to control pressure of the mobile
phase within the column, wherein the primary pressure control
element is an active back pressure regulator;
a detector located downstream of the primary pressure
control element; and
a secondary pressure control element located
downstream of the primary pressure control element and
disposed to maintain a pressure of the mobile phase above a
threshold value between an outlet of the primary pressure
control element and a point of detection within the detector.
18. A device for managing pressure within a CO2-based
chromatography system, the device comprising:
a pressure control element having a diameter between
0.1 microns and 100 microns, and a length between 0.1
microns and 100 centimeters;
a first end of the pressure control element disposed to
receive a fluid from a back pressure regulator; and
a second end of the pressure control element disposed to
transmit the fluid to a detector;
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wherein the pressure control element is disposed to
maintain a pressure of the fluid above a threshold value.
Appeal Br. 21, 24 (Claims Appendix). Claim 10, which is the other
independent claim involved in this Appeal, is directed to “[a] method
of controlling pressure of a mobile phase in a CO2-based
chromatography system” and requires a secondary pressure control
element to “maintain a pressure of the mobile phase above a threshold
value between an outlet of the primary pressure control element and a
point of detection within a detector,” similar to independent claim 1.
Id. at 22–23.

ANALYSIS
We review the appealed rejections for error based upon the issues
Appellant identifies, and in light of the arguments and evidence produced
thereon. Ex parte Frye, 94 USPQ2d 1072, 1075 (BPAI 2010) (precedential)
(cited with approval in In re Jung, 637 F.3d 1356, 1365 (Fed. Cir. 2011)
(“[I]t has long been the Board’s practice to require an applicant to identify
the alleged error in the examiner’s rejections.”)). After considering the
argued claims in light of each of Appellant’s arguments, we are not
persuaded Appellant has identified reversible error in the appealed
rejections.
The Examiner rejects claims 1, 3–10, and 12–20 as follows for the
reasons provided in the Final Office Action.3 Final Act. 6–14.

3 The Examiner interprets the following claim terms to cover the
corresponding structure described in the Specification as performing the
claimed function and equivalents thereof because they use a generic
placeholder coupled with functional language: “a primary pressure control
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Claim(s) 35 U.S.C. § Basis/Reference(s)
1, 3, 5, 7, 9,
10, 12, 15, 17 103 Kumar,
4 Fogwill5
4, 13 103 Kumar, Fogwill, Fogwill ’0006
6, 14 103 Kumar, Fogwill, Maiefski7
8, 16 103 Kumar, Fogwill, Cortes8
18, 19 103 Kumar, Cortes, Fogwill
20 103 Kumar, Cortes, Fogwill, Maiefski

Obviousness of Claim 1 over Kumar and Fogwill
Appellant argues the obviousness rejection of claims 1, 3, 5, 7, 9, 10,
12, 15, and 17 as a group. Appeal Br. 9–17. Therefore, we confine our
discussion to claim 1, which we select as representative. Claims 3, 5, 7, 9,
10, 12, 15, and 17 stand or fall with claim 1. See 37 C.F.R. § 41.37(c)(1)(iv).
The Examiner finds Kumar discloses a system for controlling pressure
of a mobile phase including claim 1’s requirements, except Kumar discloses
the primary pressure control element is a restrictor without explicitly
teaching the primary pressure control element can be a BPR. Final Act. 6
(citing Kumar Fig. 1). The Examiner determines it would have been obvious
to a person having ordinary skill in the art to substitute Kumar’s primary
structure for maintaining pressure upstream from the detector with Fogwill’s
BPR because Fogwill’s disclosure shows both are well known structures for

element,” “a secondary pressure control element,” and “a pressure control
element.” Final Act. 4 (citing 35 U.S.C. § 112(f)). Appellant does not
challenge the Examiner’s claim interpretation.
4 US 4,814,089, issued Mar. 21, 1989.
5 US 2015/0101393 A1, published Apr. 16, 2015.
6 US 2015/0301000 A1, published Oct. 22, 2015.
7 US 6,358,414 B1, issued Mar. 19, 2002.
8 US 5,340,475, issued Aug. 23, 1994.
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achieving the predictable result of maintaining pressure upstream from a
detector. Id. at 6–7 (citing Fogwill ¶ 93).
Kumar’s Figure 1 is shown below.

Kumar’s Figure 1 above depicts column 2, downstream first restrictor
26, second restrictor 28 adapted to receive process fluid from first restrictor
26, detector means 36 for analyzing the processed fluid from second
restrictor 28, tee 46 for providing a mixing area for auxiliary carrier fluid
passed from pump 10 through second conduit means 38 to tee 46, and
control valve 52 for altering the pressure of the entering auxiliary fluid to
create a backpressure within column 2 so as to control the flow rate of the
fluid sample within column 2. Kumar 5:44–6:32.
According to Appellant, the Examiner erred in determining that
Kumar’s system as modified by Fogwill satisfies claim 1’s requirement that
the secondary pressure control element “maintain a pressure of the mobile
phase above a threshold value between an outlet of the primary pressure
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control element and a point of detection within the detector.” Appeal Br. 9–
10 (pertinent portion of claim 1 quoted). Appellant contends (1) the outlet of
Kumar’s first restrictor 26 does not flow to second restrictor 28 due to
Kumar’s tee junction and (2) it is Kumar’s auxiliary stream into the tee
junction that controls the pressure value at the outlet of the first restrictor
rather than Kumar’s second restrictor 28. Id. at 10 (citing Kumar 8:35–39).
Appellant’s arguments do not persuade us that the Examiner
reversibly erred in rejecting claim 1 as obvious over Kumar modified by
Fogwill’s teaching for essentially the reasons the Examiner provides in the
Final Office Action and the Answer. We add the following primarily for
emphasis.
The preponderance of the evidence in this Appeal record supports the
Examiner’s determination that Fogwill’s disclosure of “[a] BPR, a fixed
regulator, or a thermally modulated variable restrictor can be used to
maintain system pressure upstream of the detector” means replacing
Kumar’s primary pressure fixed regulator with a BPR would have been a
simple substitution of one known element for another to obtain the
predictable result of maintaining system pressure upstream of the detector.
Ans. 3–4 (citing Fogwill ¶ 93); see KSR Int’l Co. v. Teleflex Inc., 550 U.S.
398, 416 (2007) (“[W]hen a patent claims a structure already known in the
prior art that is altered by the mere substitution of one element for another
known in the field, the combination must do more than yield a predictable
result.”).
Appellant’s argument that Kumar’s tee junction means flow from
Kumar’s primary pressure control does not flow to Kumar’s secondary
pressure control is not persuasive of error because claim 1 does not preclude
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Kumar’s tee junction between the required primary and secondary pressure
regulators. During examination, the claims must be interpreted as broadly as
their terms reasonably allow. In re Am. Acad. of Sci. Tech Ctr., 367 F.3d
1359, 1369 (Fed. Cir. 2004). The Examiner’s interpretation of claim 1
permitting other components such as Kumar’s tee junction between the
primary and secondary pressure regulators is proper because claim 1 recites
“comprising.” Thus, claim 1 permits additional pressure regulators in the
recited system.
Appellant’s argument that Kumar’s tee junction and auxiliary flow
control the pressure value at the outlet of the first restrictor rather than
Kumar’s second restrictor 28 (Appeal Br. 10; Reply Br. 6) is not persuasive
of error because the record supports the Examiner’s finding that Kumar’s
restrictor 28 functions to maintain system pressure above a certain value.
Ans. 3 (citing Fogwill ¶ 93). Fogwill teaches this is the function of a
restrictor and claim 1 does not recite a value for the threshold. Fogwill ¶ 93.
Thus, modifying Kumar with Fogwill’s teaching meets claim 1’s
requirement that the secondary pressure control element function at a
location “between an outlet of the primary pressure control element and a
point of detection within the detector.”
Appellant’s additional argument (Appeal Br. 13) that Fogwill
discloses a BPR in a split-flow configuration making the BPR downstream
from the detector is not persuasive of error because the Examiner does not
rely on Fogwill’s system structure, but, rather, relies on Fogwill’s teaching
that a BPR or a fixed restrictor are substitutes used to maintain system
pressure upstream of the detector. Ans. 4–5. The record supports the
Examiner’s finding. Fogwell ¶ 93. Moreover, “[t]he test for obviousness is
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not whether the features of a secondary reference may be bodily
incorporated into the structure of the primary reference . . . . Rather, the test
is what the combined teachings of those references would have suggested to
those of ordinary skill in the art.” In re Keller, 642 F.2d 413, 425 (CCPA
1981); see also In re Sneed, 710 F.2d 1544, 1550 (Fed. Cir. 1983) (“[I]t is
not necessary that the inventions of the references be physically combinable
to render obvious the invention under review.”); In re Nievelt, 482 F.2d 965,
968 (CCPA 1973) (“Combining the teachings of references does not involve
an ability to combine their specific structures.”).
In sum, Appellant’s arguments are not persuasive of error in the
Examiner’s conclusion of obviousness. Accordingly, we affirm the
Examiner’s rejection of claim 1 as well as the rejection of claims 3, 5, 7, 9,
10, 12, 15, and 17 under 35 U.S.C. § 103 over Kumar and Fogwill.

Obviousness of Claim 18 over Kumar, Cortes, Fogwill
Appellant argues the obviousness rejection of claims 18 and 19 over
the combination of Kumar, Cortes, and Fogwill as a group. Appeal Br. 17–
18. Therefore, we confine our discussion to claim 18, which we select as
representative. Claim 19 stands or falls with claim 18, from which it
depends. See 37 C.F.R. § 41.37(c)(1)(iv).
The Examiner finds Kumar discloses a device for managing pressure
within a CO2-based chromatography system as recited in claim 18 except
(1) the dimensions of the pressure control element and (2) that the first end
of the pressure control element is disposed to receive a fluid from a BPR.
Final Act. 12–13. The Examiner determines it would have been obvious to
substitute Kumar’s pressure control element with that of Cortes, which
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provides the claimed diameter and length dimensions, because both Kumar
and Cortes teach pressure control elements that are restrictors. Id. at 12. The
Examiner determines it would have been obvious for a skilled artisan to
substitute one well-known pressure control element for another to achieve
the predictable result of controlling the pressure of the mobile phase. Id. The
Examiner finds Fogwill teaches a pressure regulator that is an active BPR
for maintaining pressure upstream from a detector. Id. at 13. The Examiner
determines it would have been obvious to a person having ordinary skill in
the art to substitute Fogwill’s BPR for Kumar’s regulator because both are
well known structures for achieving the predictable result of maintaining
pressure upstream from a detector. Id.
Appellant argues we should reverse the Examiner’s rejection because
Cortes makes no mention of positioning a restrictor downstream of an active
BPR to maintain a fluid pressure above a certain threshold between a
pressure control element and a detector. Appeal Br. 17–18. Appellant
contends Cortes’ conduit 50 is part of restrictor interface 26 decompresses a
supercritical fluid and uses porous impactor 54 to dissipate kinetic energy
caused by the decompression. Id. at 18.
Appellant also argues that claim 18 requires a single flow path from
the BPR through the pressure control element and to the detector, which is
completely contrary to (1) Kumar’s use of tee 46 to control pressure because
tee 46 introduces an auxiliary stream between the two restrictors and
(2) Fogwill’s split-flow design, where a single pressure regulator is located
in a separate flow path from the detector. Id. at 18–19.
Appellant’s arguments do not persuade us that the Examiner
reversibly erred in rejecting claim 18 as obvious over Kumar modified by
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Fogwill’s and Cortes’ teachings for essentially the reasons the Examiner
provides in the Final Office Action and the Answer. We add the following
primarily for emphasis.
The preponderance of the evidence supports the Examiner’s finding
that Kumar and Cortes both teach pressure control elements that are
restrictors, and, therefore, it would have been obvious to substitute Cortes’
restrictor for Kumar’s restrictor. Final Act. 12. The preponderance of the
evidence in this Appeal record also supports the Examiner’s determination
that replacing Kumar’s primary pressure fixed regulator with a BPR would
have been a simple substitution of one known element for another to obtain
the predictable result of maintaining system pressure upstream of the
detector. Ans. 3–4 (citing Fogwill ¶ 93); see KSR, 550 U.S. at 416 (“[W]hen
a patent claims a structure already known in the prior art that is altered by
the mere substitution of one element for another known in the field, the
combination must do more than yield a predictable result.”).
Appellant’s arguments (Appeal Br. 17–19) that neither Fogwill nor
Cortes discloses a restrictor downstream from an active BPR are not
persuasive of error because the Examiner does not rely on either Fogwill or
Cortes’ system structures. Rather, the Examinerrelies on Cortes’ restrictor
dimensions for the restrictor disclosed in Kumar’s system and Fogwell’s
teaching that both BPRs and fixed restrictors can be used to maintain system
pressure upstream of a detector. Ans. 5–6; Final Act. 12. Appellant does not
dispute that Cortes and Kumar both disclose pressure control elements that
are restrictors and that Cortes’ restrictor meets the dimensions claim 18
requires.
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Appellant’s assertion that claim 18 requires a flow path that differs
from that of Kumar is not persuasive of error because, similar to claim 1,
claim 18 recites “comprising.” Thus, claim 18 also permits other
components, such as Kumar’s tee junction, between the primary and
secondary pressure regulators.
In sum, Appellant has not identified error in the Examiner’s rejection
of claim 18 over Kumar, Cortes, and Fogwill. Accordingly, we sustain the
Examiner’s rejection of claims 18 and 19.

Remaining Obviousness Rejections
Appellant argues that we should reverse the Examiner’s remaining
obviousness rejections for the same reasons discussed above in connection
with independent claims 1 and 18 because the additional references do not
cure the deficiencies of Kumar, Fogwill, and Cortes. Appeal Br. 19. Because
Appellant has not identified error in the Examiner’s rejections of claims 1
and 18, we sustain each of the Examiner’s obviousness rejections of claims
4, 6, 8, 13, 14, 16, and 20.

CONCLUSION
For these reasons and those provided in the Final Office Action and
the Examiner’s Answer, we uphold the Examiner’s rejections of claims 1, 3–
10, and 12–20.
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DECISION SUMMARY
In summary:
Claim(s)
Rejected 35 U.S.C. § Reference(s)/Basis  Affirmed Reversed
1, 3, 5, 7, 9,
10, 12, 15,
17
103 Kumar, Fogwill
1, 3, 5, 7, 9,
10, 12, 15,
17

4, 13 103 Kumar, Fogwill, Fogwill ’000 4, 13
6, 14 103 Kumar, Fogwill, Maiefski 6, 14
8, 16 103 Kumar, Fogwill, Cortes 8, 16
18, 19 103 Kumar, Cortes, Fogwill 18, 19
20 103 Kumar, Cortes, Fogwill, Maiefski 20
Overall
Outcome
1, 3–10,
12–20

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). See 37
C.F.R. § 1.136(a)(1)(iv).

AFFIRMED