MANAGED PRESSURE OPERATIONS PTE. LTD.

Patent Trials and Appeals Board

Dec 28, 2020

2020001760 (P.T.A.B. Dec. 28, 2020)

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.
15/305,349 10/20/2016 Christian LEUCHTENBERG MPO 1630 US-PAT 2759
96897 7590 12/28/2020
THOT PATENT
POSTFACH 10 17 56
RATINGEN, 40837
GERMANY
EXAMINER
GRAY, GEORGE STERLING
ART UNIT PAPER NUMBER
3676
MAIL DATE DELIVERY MODE
12/28/2020 PAPER
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.
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte CHRISTIAN LEUCHTENBERG

Appeal 2020-001760
Application 15/305,349
Technology Center 3600
____________

Before ANTON W. FETTING, MICHAEL C. ASTORINO, and
BRUCE T. WIEDER, Administrative Patent Judges.

ASTORINO, Administrative Patent Judge.

DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134(a), the Appellant1 appeals from the
Examiner’s decision to reject claims 36–44 and 47–54. We have jurisdiction
under 35 U.S.C. § 6(b).
We AFFIRM.

1 We use the word “Appellant” to refer to “applicant” as defined in
37 C.F.R. § 1.42. The Appellant identifies the real party in interest as
Managed Pressure Operations Pte. Ltd. Appeal Br. 2.
Appeal 2020-001760
Application 15/305,349

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STATEMENT OF THE CASE
Subject Matter on Appeal
The subject matter on appeal “relates to an improved method of
operating a drilling system for drilling a subsea or subterranean well bore for
oil and/or gas production.” Spec. ¶ 2.
Claims 36 and 54 are the independent claims on appeal. Claim 36,
recites:
36. A method of operating a drilling system for drilling a
subterranean bore hole, the drilling system comprising:
a drill string configured to rotate during a drilling;
a first sealing device configured to provide a
substantially fluid tight seal around the drill string while the
drill string is rotating during the drilling and to exert a sealing
pressure which is variable on the drill string when operated to
seal against the drill string; and
a second sealing device arranged above the first sealing
device, the second sealing device being configured to provide a
substantially fluid tight seal around the drill string while the
drill string is rotating during the drilling and to exert a sealing
pressure which is variable on the drill string when operated to
seal against the drill string,
the method comprising:
injecting a fluid into an annular volume around the drill
string between the first sealing device and the second sealing
device;
controlling a fluid pressure in the annular volume around
the drill string between the first sealing device and the second
sealing device so that said fluid pressure is greater than a fluid
pressure in the annular volume around the drill string directly
below the first sealing device and greater than a fluid pressure
in the annular volume around the drill string directly above the
second sealing device; and
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at least one of,
varying the sealing pressure exerted by the first
sealing device on the drill string to establish a leakage of
the fluid injected between the first sealing device and the
drill string at a desired rate, and
varying the sealing pressure exerted by the second
sealing device on the drill string to establish a leakage of
the fluid injected between the second sealing device and
the drill string at a desired rate.
Appeal Br. 21–22.
Independent claim 54 recites “[a] tangible computer readable
medium comprising instructions installed thereon which, when
executed by a processing device, cause the processing device to
perform a method of operating a drilling system for drilling a
subterranean bore hole,” where the method is the same as the method
of claim 36. Id. at 26.
References
The prior art relied upon by the Examiner is:
Name Reference Date
Knox US 2,609,836 Sept. 9, 1952
Bailey et al. (“Bailey”) US 2006/0144622 A1 July 6, 2006
Leuchtenberg
(“Leuchtenberg’149”)
US 2008/0041149 A1 Feb. 21, 2008
Hoyer et al. (“Hoyer”) US 2011/0024195 A1 Feb. 3, 2011
Gray US 2014/0069720 A1 Mar. 13, 2014
Atherton US 2014/0299210 A1 Oct. 9, 2014
Leuchtenberg
(“Leuchtenberg’690”)
WO 2011/128690 A1 Oct. 20, 2011

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Rejections
Claims 36–39, 42, and 52–54 are rejected under 35 U.S.C. § 103 as
unpatentable over Hoyer in view of Knox.2
Claims 40, 41, 43, 44, 47, and 48 are rejected under 35 U.S.C. § 103
as unpatentable over Hoyer in view of Knox and Leuchtenberg’690.
Claim 49 is rejected under 35 U.S.C. § 103 as unpatentable over
Hoyer in view of Knox, Leuchtenberg’690, and Atherton.
Claims 50 and 51 are rejected under 35 U.S.C. § 103 as unpatentable
over Hoyer in view of Knox, Leuchtenberg’690, Atherton, Gray, and
Official Notice.

ANALYSIS
The Appellant argues that the teachings of Hoyer and Knox cannot be
combined as proffered by the Examiner to teach the “varying the sealing
pressure” recitation of independent claims 36 and 54; i.e.,
at least one of,
varying the sealing pressure exerted by the first sealing
device on the drill string to establish a leakage of the fluid
injected between the first sealing device and the drill string at a
desired rate, and
varying the sealing pressure exerted by the second
sealing device on the drill string to establish a leakage of the
fluid injected between the second sealing device and the drill
string at a desired rate.
Appeal Br. 10 (emphasis omitted); see id. at 12–15; Reply Br. 6–10. The
Appellant acknowledges that the Examiner’s rejection relies on Hoyer’s

2 The Examiner finds that Hoyer incorporates by reference
Leuchtenberg’149 and Bailey. Final Act. 3 (citing Hoyer ¶ 17).
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teaching of a rotating control device for drilling wells having two sealing
elements (Appeal Br. 10–12 (citing Hoyer, Fig. 9)), but asserts that
“nowhere does Hoyer expressly teach or suggest the use of two (2) active
sealing elements and none of the embodiments described by Hoyer have
such a combination” (id. at 12). The Appellant’s assertion is not persuasive
of Examiner error.
The Examiner correctly finds that Hoyer teaches the use of two active
sealing elements for the embodiment of Figure 9. See Final Act. 3–4;
Ans. 14. The Examiner explains, “Hoyer specifically indicates, for all
embodiments of Figs. 7–17B, that ‘it is contemplated that passive sealing
elements and active sealing elements may be used interchangeably’ and,
also, that plural active sealing elements are contemplated.” Ans. 14 (citing
Hoyer ¶ 88).
The Appellant contends Hoyer does not teach the “varying the sealing
pressure” recitation of claims 36 and 54. Appeal Br. 13–14. Notably,
however, the Examiner relied on Knox to teach the “varying the sealing
pressure” recitation of claims 36 and 54 and the combined teachings of
Hoyer and Knox to reject these claims. See Final Act. 5–6; Ans. 15.
The Appellant asserts that Hoyer does not teach “intentionally
establish[] a leak rate,” rather “Hoyer expressly teaches the exact opposite
when it describes pressurizing active sealing element 190 ‘to increase
sealing with drill string DS if the PLC [(i.e., programmable logic controller)]
222 determines leakage between the tubular and active sealing element
190.’” Appeal Br. 14 (quoting Hoyer ¶ 91); see also Hoyer ¶ 40. According
to the Appellant,
[b]y varying the pressure exerted by a sealing element on a drill
string to at best prevent leakage, rather than allowing a leakage
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to occur, Hoyer expressly teaches away from the concept of
varying the sealing pressure exerted by the sealing device on
the drill string to establish an intentional leakage at a desired
rate.
Appeal Br. 14; see Reply Br. 10. On this basis, the Appellant argues that the
Examiner’s proffered combination constitutes improper hindsight reasoning.
Appeal Br. 15. The Appellant’s argument is not persuasive of Examiner
error.
A reference teaches away “when a person of ordinary skill, upon
reading the reference, would be discouraged from following the path set out
in the reference, or would be led in a direction divergent from the path that
was taken” in the claim. Galderma Labs., L.P. v. Tolmar, Inc., 737 F.3d
731, 738 (Fed. Cir. 2013). A reference that “merely expresses a general
preference for an alternative invention but does not criticize, discredit, or
otherwise discourage investigation into” the claimed invention does not
teach away. Id.
The sentence of Hoyer that the Appellant quotes from paragraph 91
recites, with italics added, “[a]ctive sealing element 190 may be pressurized
to increase sealing with drill string DS if the PLC 222 determines leakage
between the tubular and active sealing element 190.” This sentence teaches,
by use of the word “may,” that pressurizing the active sealing element to
increase sealing if leakage is determined is permissive, i.e., not mandatory.
In the Examiner’s words, “increasing the sealing pressure as a reaction to
leakage (i.e. stopping the leakage) across the active sealing element is stated
as an optional course of action which ‘may’ be chosen for a particular
circumstance.” Ans. 14–15 (italics added). Moreover, the Examiner
explains that the sentence “is not a statement indicating that leakage is
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undesirable in all circumstances, such that a person of ordinary skill in the
art would avoid establishing leakage for useful purposes.” Id. at 15. We
determine that one of ordinary skill in the art would not be discouraged from
following the path in Hoyer or be led in a direction divergent from the path
taken in the disputed claims. In other words, we determine that Hoyer does
not teach away from the concept of varying the sealing pressure exerted by
the sealing device on the drill string to establish an intentional leakage at a
desired rate.
We have considered the Appellant’s remaining points raised in the
Appeal Brief at pages 12–15 and the Reply Brief at pages 6–10 and
determined that they are not persuasive of Examiner error.
Thus, we sustain the Examiner’s rejection of independent claims 36
and 54, and dependent claims 37–39, 42, 52, and 53.
The Appellant provides separate headings for each of the remaining
rejections on appeal. Appeal Br. 15–19. The arguments for each of the
remaining rejections are similar; the Appellant reiterates the argument for
claim 36 and adds that the additional cited prior art (i.e., Leuchtenberg’690,
Atherton, Gray, and/or Official Notice) does not cure the alleged deficiency
in the rejection of claim 36. See id. As discussed above, the argument
against the Examiner’s rejection of claim 36 is not persuasive and, therefore,
the Appellant’s subsequent argument that the additional prior art does not
cure the alleged deficiency in the rejection of claim 36 is also not persuasive.
Thus, we sustain the Examiner’s rejection of dependent claims 40, 41,
43, 44, and 47–51.

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CONCLUSION
In summary:
Claims
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
36–39, 42,
52–54
103 Hoyer, Knox 36–39,
42, 52–54

40, 41, 43,
44, 47, 48
103 Hoyer, Knox,
Leuchtenberg’690
40, 41, 43,
44, 47, 48

49 103 Hoyer, Knox,
Leuchtenberg’690,
Atherton
49
50, 51 103 Hoyer, Knox,
Leuchtenberg’690,
Atherton, Gray,
Official Notice
50, 51
Overall
Outcome
36–44,
47–54

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