BAKER HUGHES INCORPORATED

Patent Trials and Appeals Board

May 28, 2020

14957589 - (D) (P.T.A.B. May. 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.
14/957,589 12/02/2015 Scott G. Nelson 020569-36700
(CT4-58286)
3468
71762 7590 05/28/2020
JONES DELFLACHE LLP
1333 HEIGHTS BOULEVARD
SUITE 300
HOUSTON, TX 77008
EXAMINER
SUE-AKO, ANDREW B.
ART UNIT PAPER NUMBER
3674
MAIL DATE DELIVERY MODE
05/28/2020 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 SCOTT G. NELSON, JIMIE DEVON LEMONS,
D.V. SATYANARAYANA GUPTA, HAROLD DEAN BRANNON,
ANNA JENSEN, BENJAMIN TATUM, and ALEXANDER PIROGOV
Appeal 2019-003145
Application 14/957,589
Technology Center 3600
Before DANIEL S. SONG, JILL D. HILL, and MICHAEL L. WOODS,
Administrative Patent Judges.
SONG, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 1–11, 15, 20, and 22–30. 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(a). Appellant identifies the real party in interest as Baker Hughes
Incorporated. Appeal Br. 1.
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Application 14/957,589
2
CLAIMED SUBJECT MATTER
The claims are directed to a method of enhancing circulation during
drill-out of a wellbore barrier using dissolvable solid particulates. Claim 1,
reproduced below, is illustrative of the claimed subject matter:
1. A method of enhancing the efficiency in the removal of
debris from a wellbore penetrating a multi-zoned subterranean
reservoir wherein the debris originates, at least in part, from more
than one fluid-impermeable barrier separating perforated zones,
the method comprising:
(a) breaking a fluid-impermeable barrier which separates
two perforated zones into pieces and creating a flow path
between the perforated zones;
(b) circulating a fluid through the well bore and into the
created flow path, wherein the fluid comprises water or brine and
dissolvable solid particulates;
(c) collecting debris within the flow path in the circulating
fluid, wherein the debris includes pieces broken from the fluid-
impermeable barrier in step (a);
(d) preventing flow of the circulating fluid with the
collected debris into the perforated zones by plugging perforation
clusters with the dissolvable solid particulates;
(e) removing the circulating fluid with the collected debris
from the well bore;
(f) after removal of the collected debris from the well bore,
breaking another fluid impermeable barrier farther removed from
the wellbore into pieces and creating a flow path between
perforated zones separated by the another fluid-impermeable
barrier; and
(g) repeating steps (b) through (f).
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REFERENCES
The prior art relied upon by the Examiner is:
Name Reference Date
Ischy et al. US 5,990,051 Nov. 23, 1999
Willberg et al. US 2008/0200352 A1 Aug. 21, 2008
Williamson US 2011/0036564 A1 Feb. 17, 2011
Shkurti et al. US 2011/0259610 A1 Oct. 27, 2011
Gupta US 2013/0341025 A1 Dec. 26, 2013
REJECTIONS
The Examiner rejects various claims under 35 U.S.C. § 103 as
follows:
1. Claims 1–5, 10, 11, 15, 20, and 22–25 as unpatentable over
Williamson in view of Willberg, as evidenced by Ischy. Final Act. 3.
2. Claims 6–9 as unpatentable over Williamson in view of
Willberg, as evidenced by Ischy, further in view of Gupta. Final Act. 12.
3. Claim 30 as unpatentable over Williamson in view of Willberg,
as evidenced by Ischy, and further in view of Shkurti. Final Act. 13.
4. Claims 26–28 as unpatentable over Williamson in view of
Willberg and Shkurti, as evidenced by Ischy. Final Act. 13.
5. Claim 29 as unpatentable over Williamson in view of Willberg
and Shkurti, as evidenced by Ischy, and further in view of Gupta. Final Act.
17.
OPINION
Rejection 1: Williamson, Willberg, Ischy
The Examiner rejects claims 1–5, 10, 11, 15, 20, and 22–25 as
unpatentable over Williamson in view of Willberg, as evidenced by Ischy.
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4
Final Act. 3. The Appellant argues all of the claims in this rejection
together, and thus, we select claim 1 as representative.
As to independent claim 1, the Examiner finds that Williamson
discloses the invention substantially as claimed, including the recited steps
of “(a) breaking a fluid-impermeable barrier which separates two
perforated zones into pieces and creating a flow path between the
perforated zones.” Final Act. 3–4. The Examiner concedes that
Williamson does not describe the fluid as comprising “water or brine and
dissolvable solid particulates.” Final Act. 5. The Examiner relies on
Willberg for disclosing such a circulating fluid for well bore2 cleanout, and
concludes that it would have been obvious to one of ordinary skill in the art
to have used the circulating fluid of Willberg in Williamson for well bore
cleanout. Final Act. 5. The Examiner further explains that claim 1 is
obvious because it is
no more than the use of familiar elements (known degradable
materials as in Willberg) according to known techniques
(known milling/cleaning as in Williamson and known plugging
perforations with a cleaning fluid as in Willberg) in a manner
that achieves predictable results (known multi-zonal fracturing
treatment as in Williamson).
Final Act. 6.
The Appellant initially argues that “[t]here is no disclosure in
Williamson to the plugging of a perforation cluster” or disclosure “relating to
dissolvable solid particulates in a circulating fluid.” Appeal Br. 7, citing
Williamson ¶ 34. However, the rejection relies on Willberg for disclosing
such a fluid having dissolvable solid particulates that would plug the
perforation cluster upon circulation. Final Act. 3; see also Ans. 4 (“these

2 The record utilizes the terms “well bore” and “wellbore” interchangeably.
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5
limitations are taught by Willberg.”); Willberg, Abstract, ¶¶ 33, 35.
“Non-obviousness cannot be established by attacking references individually
where the rejection is based upon the teachings of a combination of
references.” In re Merck, 800 F.2d 1091, 1097 (Fed. Cir. 1986); In re
Keller, 642 F.2d 413, 425 (CCPA 1981).
The Appellant also argues that “Williamson relates to removing the
plugs intact in a single step.” Appeal Br. 10; see also Reply Br. 3
(“Williamson teaches a mechanical device which enables the removal
(retrieval) of all of the plugs in tandem upon completion of stimulation.”).
Accordingly, the Appellant argues that “the circulating fluid of Williamson
would not flow ‘past the removed plug down to the next plug,’” and that
Williamson “only discloses a circulating fluid as the fluid which removes
debris prior to movement of the barrier downward to the lower barrier.”
Appeal Br. 8–9.
These arguments are unpersuasive because the Appellant only focuses
on a typical mode of operation disclosed in Williamson, and does not
address the rejection, which is based on Williamson’s additional teaching of
milling the plug if it is stuck. In particular, as the Examiner points out and
explains, Williamson discloses that “[a]s an added advantage, the plug’s
components in this set condition are prevented from rotating, which can
make milling of the plug 100 easier if needed when the plug 100 is stuck or
the like.” Williamson ¶ 46; Final Act. 3; Ans. 5. Thus, the rejection is
based on Williamson’s disclosure of milling of the plug, not on its tandem
removal of the plugs.
The Appellant further argues that milling of the plug disclosed in
Williamson “does not suggest or imply that a flow path is created as
claimed,” and that “[t]here simply is no reason to conclude that the upper
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6
plug of Williamson is milled into pieces to the extent the barrier is broken or
removed such that a flow path is created.” Appeal Br. 10, 11. The
Appellant asserts that milling in Williamson “only relates to the plugging of
the zones during the stimulation operation.” Reply Br. 5. We do not find
these arguments persuasive. To the contrary, we agree with the Examiner’s
finding that:
“Milling of the plug” refers to, e.g., “In milling, a milling cutter is
used to grind the tool, or at least the outer components thereof, out of
the well bore” (see Shkurti [0010]). Appellant even uses the same
meaning for “milling” in the Specification (e.g., [0004] “In drill-out,
the barrier is first milled leaving behind debris, such as rubber and
metal”).
Ans. 5.
Indeed, Shkurti clearly evidences that “milling of plugs” as used in the
art of well bore drilling, refers to the process of removing the plugs from the
well bore, and the evidence further indicates that such milling of the plugs is
a well-known practice in the art of drilling well bores. See Shkurti ¶ 10 (“In
milling, a milling cutter is used to grind the tool, or at least the outer
components thereof, out of the well bore.”); ¶ 59 (“during a drilling/milling
process, i.e. drilling/milling the frac plug out of the casing, the cones 110,
112, element barrier assemblies 116, and sealing element 114 are more
easily and quickly drilled out, because the components do not spin relative to
one another.”); ¶ 105 (“it may be more economical to drill out or mill out the
frac plug, and the designs and materials of each component of the frac plug
may be chosen with this end in mind.”).
Accordingly, based on the preponderance of the evidence, we agree
with the Examiner that Williamson “disclose[s] milling/drilling/breaking
into pieces the plug, as claimed.” Ans. 5. Moreover, based on the
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preponderance of the evidence, we further agree with the Examiner that it
does not make sense that “a milling cutter could grind the plug out of the
well bore and yet the plug would not be broken or removed such that a flow
path is created,” and find that such a flow path would be created upon
milling. Ans. 6; see also In re Jacoby, 309 F.2d 513, 516 (CCPA 1962) (an
artisan must be presumed to know something about the art apart from what
the references disclose); Randall Mfg. v. Rea, 733 F.3d 1355, 1362–63 (Fed.
Cir. 2013) (prior art of record not specifically relied upon in the rejection
considered as evidence of the state of the art, common knowledge, and
common sense of one of ordinary skill in the art). The Appellant has not
provided any persuasive evidence or argument that establishes the contrary.
The Appellant also argues that Williamson “do[es] not reference
milling of the plug and then clearing debris prior to releasing the upper
plug,” and “does not disclose removing the plug in between the clearing
away of debris from two zones.” Reply Br. 7. These arguments are again
unpersuasive in view of the above discussion. In accordance with the
disclosure of Williamson, debris is initially cleared from the plug, for
example, the upper plug, so that it can be removed. However, if the plug is
stuck, it is milled, and thus, removed. Milling of the plug results in the
adjacent perforated zones previously separated by the plug to be fluidically
connected such that the debris of the milled plug now resides in the two
connected perforated zones. In seeking to remove the subsequent lower
plug, the debris stemming from the milled plug is also cleared from the
lower plug. Thus, milling of the upper plug would necessarily precede
circulating fluid to clear debris from the subsequent lower plug, and the
Examiner is correct that “the debris is also removed from the 2nd plug after
the removal of the uppermost bridge plug by milling, as claimed.” Ans. 6;
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see also Ans. 4 (“(a) milling of the plug . . . . precedes (b) circulating fluid to
clear debris. . . . Williamson plainly discloses washing the plug of debris,
removing the plug, washing the next plug of debris, removing the next plug,
etc. Appellant has not actually provided any evidence otherwise.”).
The Appellant also asserts that “the milling of the plug referenced by
Williamson does not occur during the retrieval process of the plug.” Reply
Br. 8. We find no basis for this assertion, and the relevance thereof is not
readily apparent considering that as discussed above, the teachings of
Williamson results in the recited steps of claim 1.
The Appellant further argues that in the claimed invention, the
collected debris “includes pieces from the barrier (plug). Williamson doesn’t
reference removing debris originating from the plug with the circulating
fluid. The debris removed in Williamson is the debris from the fracturing
operation.” Appeal Br. 11. Likewise, the Appellant argues that “Willberg
provides no indication that a fluid containing a degradable material could be
circulated into the wellbore after breaking apart a fluid-impermeable barrier.
Neither does Willberg provide any indication for the removal of collected
debris from the wellbore in the fluid.” Appeal Br. 14–15; see also Reply Br.
9. These arguments are unpersuasive because the debris from Willberg’s
milled plug would not have anywhere to go except into the circulating fluid.
The circulated fluid cannot distinguish the types of debris so as to remove
only the debris from fracturing at the exclusion of debris from milling.
Accordingly, we agree with the Examiner that “the milled plug debris in
Williamson would also necessarily be swept away by the circulated fluid.”
Ans. 7.
The Appellant also argues that there is no motivation to modify
Williamson in the manner suggested because “[n]othing in Williamson
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Application 14/957,589
9
suggests breaking apart the bridge plug or removal of the bridge plug, much
less creating a flow path between two perforated zones.” Appeal Br. 12–13.
This argument is unpersuasive for the reasons already addressed above in
that no modification is needed except for the use the fluid of Willberg for
well bore cleanout.
The Appellant further argues that the claimed method is continuous
and repetitive. Appeal Br. 13. However, the Examiner is correct that
“Williamson plainly discloses ‘These steps are repeated to retrieve other
bridge plugs (i.e., 100A) lower downhole.’” Ans. 7, quoting Williamson
¶ 38. Indeed, it would have been obvious to one of ordinary skill in the art
to have repeated the above discussed steps in accordance with Williamson if
multiple plugs were stuck. See also Ans. 6.
The Appellant also argues that in the claims, “the barriers are removed
in a sequential order but not in a single step,” whereas “[i]n Williamson, the
fluid-impermeable barrier is removed from the wellbore in tandem in a
single step.” Appeal Br. 14; see also Reply Br. 3. Again, while this may be
applicable to the typical mode of operation disclosed in Williamson, it is not
pertinent to the rejection that is based on the disclosure in Williamson of
milling a stuck plug.
The Appellant further argues that the Examiner’s rejection engages in
impermissible hindsight. Appeal Br. 18. However, this argument is also
unpersuasive because as discussed above, the Examiner’s rejection is based
on the actual disclosure of Williamson.
Therefore, in view of the above, it is apparent that Appellant’s
arguments do not fully consider the method steps that result from the
teachings of Williamson and how these steps satisfy the claim language.
Accordingly, we affirm the Examiner’s rejection of independent claim 1. As
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Application 14/957,589
10
noted, the Appellant argues all of the claims in this rejection together. Thus,
we likewise affirm the Examiner’s rejection of claims 2–5, 10, 11, 15, 20,
and 22–25 as well.

Rejections 2–5
The Appellant argues that Rejections 2–5 should be reversed because
the tertiary references relied upon by the Examiner in these rejections do not
cure the deficiencies of the combination of Williamson and Willberg as
applied in Rejection 1. Appeal Br. 19. However, having found no
deficiencies as to Rejection 1, we affirm Rejections 2–5 as well.
CONCLUSION
The Examiner’s rejections are affirmed.
DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
1–5, 10,
11, 15, 20,
22–25
103 Williamson,
Willberg
1–5, 10, 11,
15, 20, 22–
25

6–9 103 Williamson,
Willberg, Gupta
6–9
30 103 Williamson,
Willberg, Shkurti
30
26–28 103 Williamson,
Willberg, Shkurti
26–28
29 103 Williamson,
Willberg, Shkurti,
Gupta
29
Overall
Outcome
1–11, 15,
20, 22–30

Appeal 2019-003145
Application 14/957,589
11
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). See 37 C.F.R.
§ 1.136(a)(1)(iv).
AFFIRMED