UNITED TECHNOLOGIES CORPORATION

Patent Trials and Appeals Board

Jun 16, 2020

15027562 - (D) (P.T.A.B. Jun. 16, 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.
15/027,562 04/06/2016 Matthew A. Bennington 61680US02;
67097-2733US1
7473
54549 7590 06/16/2020
CARLSON, GASKEY & OLDS/PRATT & WHITNEY
400 West Maple Road
Suite 350
Birmingham, MI 48009
EXAMINER
EDWARDS, LOREN C
ART UNIT PAPER NUMBER
3746
NOTIFICATION DATE DELIVERY MODE
06/16/2020 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):
ptodocket@cgolaw.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte MATTHEW A. BENNINGTON
____________

Appeal 2019-006780
Application 15/027,562
Technology Center 3700
____________

Before STEFAN STAICOVICI, MICHAEL L. HOELTER, and
WILLIAM A. CAPP, Administrative Patent Judges.

STAICOVICI, Administrative Patent Judge.

DECISION ON APPEAL

STATEMENT OF THE CASE.
Appellant1 appeals under 35 U.S.C. § 134(a) from the Examiner’s
decision in the Final Office Action (dated Jan. 29, 2019, hereinafter “Final
Act.”) rejecting claims 1, 4–6, and 8–24.2 We have jurisdiction over this
appeal under 35 U.S.C. § 6(b).

1 We use the word “Appellant” to refer to “applicant” as defined in
37 C.F.R. § 1.42. United Technologies Corporation is identified as the real
party in interest in Appellant’s Appeal Brief (filed July 8, 2019, hereinafter
“Appeal Br.”) 1.
2 Claims 2, 3, and 7 are canceled. See Appellant’s Amendment (filed Mar.
21, 2019, hereinafter “Amdt.”) 2.
Appeal 2019-006780
Application 15/027,562

2

SUMMARY OF DECISION
We REVERSE.

INVENTION
Appellant’s invention relates to a casing of a gas turbine engine.
Spec. para. 3.
Claims 1, 11, and 16 are independent. Claim 1 is illustrative of the
claimed invention and reads as follows:
1. A gas turbine engine component comprising:
a casing;
an airfoil fixed to the casing to extend from a
leading edge to a trailing edge, the airfoil having a
pressure side and a suction side; and
a trench formed within the casing adjacent the
suction side of the component, the trench having a
maximum depth that is positioned at or aft of the leading
edge; and
wherein the trench is defined by a length extending
in a longitudinal direction from the leading edge to the
trailing edge and a width extending in a lateral direction
from the airfoil toward an adjacent airfoil fixed to the
casing, and wherein the width of the trench is less than a
distance between the airfoil and the adjacent airfoil.

REJECTIONS
I. The Examiner rejects claims 9, 15, and 20 under 35 U.S.C.
§ 112(a) as failing to comply with the enablement requirement.
II. The Examiner rejects claims 9, 15, and 20 under 35 U.S.C.
§ 112(a) as being indefinite.3

3 The indefiniteness rejection of claims 21, 22, and 24 is withdrawn.
Examiner’s Answer (dated Aug. 8, 2019, hereinafter “Ans.”) 7–8.
Appeal 2019-006780
Application 15/027,562

3

III. The Examiner rejects claims 1, 4–6, 8, 10–14, and 23 under 35
U.S.C. § 102(a)(1) as being anticipated by Staubach.4,5,6
IV. The Examiner rejects claims 9, 13, and 15 under 35 U.S.C.
§ 103 as being unpatentable over Staubach.7
V. The Examiner rejects claims 16–21 under 35 U.S.C. § 103 as
being unpatentable over Bunker8 and Staubach.

ANALYSIS
Rejection I
The Examiner finds the limitation of an “aerodynamic loading factor
that is greater than or equal to a value of 0.5,” as recited in each of claims 9,
15, and 20, is not enabled because “there is no upper bounds defined for this
range,” and, thus, “the aerodynamic loading factor could theoretically
approach infinity . . . and the [S]pecification fails to provide explanations of
how this would be achieved.” Final Act. 7; see also Appeal Br. 14–16
(Claims App.). According to the Examiner,
[O]ne of ordinary skill would have to greatly experiment with
the materials, geometry, etc. to achieve a large amount of the
claimed scope. Even taking the level of ordinary skill and the

Appellant’s amendment of claims 21, 22, and 24 (see Amdt. 6) was entered
by the Examiner in the Advisory Action dated April 19, 2019.
4 Staubach et al., US 2003/0170124 A1, published Sept. 11, 2003.
5 The anticipation rejection of claims 22 and 24 based upon Staubach is
withdrawn. See Ans. 3.
6 As claim 13 depends indirectly from claim 11 and includes all the
limitations of claim 11, we have included here the rejection of claim 13
under 35 U.S.C. § 102(a)(1). See Final Act. 27.
7 For simplicity, we have included here the rejection of claim 13 under 35
U.S.C. § 103. See Final Act. 27–28.
8 Bunker et al., US 6,183,197 B1, issued Feb. 6, 2001.
Appeal 2019-006780
Application 15/027,562

4

predictability of the art in a light most favorable to the
Applicant, the sheer breadth of the claims coupled with the lack
of direction and working examples throughout the scope
amounts to undue experimentation.

Final Act. 9 (emphasis added).
Appellant argues that “one of ordinary skill in the art would recognize
that the aerodynamic loading factor has an inherent upper limit based on the
practical physical limitations and basic architecture of a bypass turbine
engine.” Appeal Br. 4 (citing Ex parte Feulner, Appeal No. 2013-010469
(PTAB Oct. 23, 2015), Ex parte Kohlenberg, Appeal No. 2017-000822
(PTAB June 8, 2018)). According to Appellant, a skilled artisan would
recognize from the description of the aerodynamic loading factor in
paragraphs 42 and 43 of the Specification that it “has an inherent practical
and physical upper limit.” Id. at 5 (emphasis added). Moreover, Appellant
notes that “[t]he Examiner’s focus on infinity with regard to enablement is
simply not supported” because in Scripps Clinic & Research Foundation v.
Genentech, Inc., 927 F.2d 1565 (Fed. Cir. 1991)9 “the Federal Circuit clearly
held that open-ended ranges may be enabled even if the inherent limit is ‘not
precisely known.’” Id. at 6 (citing Scripps Clinic, 927 F.2d at 1572).
Insofar as the enablement requirement is concerned, the dispositive
issue is whether Appellant’s disclosure, considering the level of ordinary
skill in the art as of the filing date of the application, would have enabled a
person of such skill to make and use Appellant’s invention without undue
experimentation. In re Strahilevitz, 668 F.2d 1229, 1232 (CCPA 1982).

9 Overruled on other grounds in Abbott Labs v. Sandoz, 556 F.3d 1282
(Fed. Cir. 2009).
Appeal 2019-006780
Application 15/027,562

5

Here, the Specification defines the aerodynamic loading factor as the ratio
between the difference of static pressures at an exit (PSexit) and at an inlet
(PSinlet) of the blade row and the difference between the total pressure (POexit)
at an exit and the static pressure at the inlet (PSinlet) of the blade row. See
Spec. paras. 42, 43. Although mathematically it may be true that the
resulting aerodynamic loading factor generated from the equation shown in
Appellant’s Specification may extend to infinity, the determination of
enablement is not merely a mathematical or theoretical exercise, as the
Examiner asserts. See Ans. 5 (“[R]egarding the formula provided by
Appellant, an analysis of this formula quickly concludes there is no upper
limit to the resulting values this formula produces.”). Rather, the claimed
aerodynamic loading factor must be considered in the context in which is it
is being applied, namely, highly loaded stator blades “in the compressor
section 24 and/or turbine section 28” of gas turbine engine 20. Spec.
paras. 33, 41.
Here, to approach infinity, a skilled artisan would have to reasonably
believe that the static pressure differential across a blade row would equal
infinity. Appellant is correct that “[o]ne of ordinary skill in the art would
understand the pressure differentials across the blades that would be
required within the atmosphere during engine operation makes an infinite
aerodynamic loading factor impractical.” Reply Brief (filed Sept. 17, 2019,
hereinafter “Reply Br.”) 2 (emphasis added). Although we appreciate the
Examiner’s position that “impractical is not the same as impossible” (see
Final Act. 3), nonetheless, we do not agree with the Examiner that “the
limitation requiring . . . ‘an aerodynamic loading factor that is greater than
or equal to a value of 0.5’, [reasonably] includes a value of infinity.” Ans. 6.
Appeal 2019-006780
Application 15/027,562

6

Furthermore, although Appellant “makes no declaration of what this
[upper] limit is” (see Ans. 5), we note that when rejecting a claim for lack of
enablement, the PTO bears the initial burden of setting forth a reasonable
explanation as to why the scope of the claim is not adequately enabled by
the description provided in the specification. In re Wright, 999 F.2d 1557,
1561–62 (Fed. Cir. 1993). Here, the Examiner has failed to present any
evidence to support a finding of an infinite aerodynamic loading factor in the
context of highly loaded stator blades of a gas turbine engine.
A skilled artisan would further recognize that there is an upper limit
less than infinity because the static and total gas pressure across the blades
of a turbine engine are determined by their configuration, i.e., geometry,
which in turn “alter[] the inner and outer surface of the flow path.” Spec.
para. 41. In particular, as the Examiner has not identified any other value
less than infinity for the aerodynamic loading factor that is not enabled,
Appellant is correct that “one of ordinary skill in the art would recognize
that the aerodynamic loading factor has an inherent practical and physical
upper limit.” Reply Br. 2 (emphasis added). In contrast to the Examiner
(see Ans. 4; Final Act. 3), such a position is similar to Feulner where in the
context of an enablement rejection the Board found that “there is an upper
limit that a skilled artisan would recognize as being less than infinity
because the hydraulic diameter is defined by actual physical parts within
. . . a turbine engine.” Feulner 9 (emphasis added).
Finally, even though determining an appropriate blade configuration
that would have an aerodynamic loading factor greater than or equal to 0.5
would require some experimentation on the part of ordinarily skilled
artisans, a disclosure may nonetheless be enabling despite the need for
Appeal 2019-006780
Application 15/027,562

7

experimentation. As noted above, the test is whether such experimentation
is undue. In re Angstadt, 537 F.2d 498, 504 (CCPA 1976). Although the
Examiner refers to the factors in In re Wands, 858 F.2d 731, 737 (Fed. Cir.
1988), the Examiner does not discuss any of these factors in establishing that
the disclosure is non-enabling. See Final Act. 4–5. As such, even though
“[t]he physical limitations of gas-turbine engines are constantly being
advanced as new materials and configurations are developed” (see Ans. 5),
Appellant is correct that the static and total gas pressures across the blades of
a turbine engine “are easily discernible by one of ordinary skill within the
mechanical working environment of a gas turbine engine.” Appeal Br. 7.
Thus, the Examiner does not set forth the requisite findings and analysis to
show adequately that a person of ordinary skill in the art would not have
been able to determine the aerodynamic loading factor by measuring static
and total gas pressures across the blades of a turbine engine; and instead
would have had to rely upon undue experimentation to do so.
In conclusion, for the foregoing reasons, we do not sustain the
rejection under 35 U.S.C. § 112(a) of claims 9, 15, and 20 as failing to
comply with the enablement requirement.

Rejection II
The Examiner finds the limitation of an “aerodynamic loading factor
that is greater than or equal to a value of 0.5,” as recited in each of claims 9,
15, and 20, is indefinite because “there is no upper bounds defined for this
range.” Final Act. 10. Thus, according to the Examiner, “the scope of the
claim[s] cannot be ascertained which renders the claim[s] indefinite.”
Ans. 7.
Appeal 2019-006780
Application 15/027,562

8

The test for definiteness under 35 U.S.C. § 112, second paragraph, is
whether “those skilled in the art would understand what is claimed when the claim
is read in light of the specification.” Orthokinetics, Inc. v. Safety Travel Chairs,
Inc., 806 F.2d 1565, 1576 (Fed. Cir. 1986). In this case, by not specifying an
upper limit to the aerodynamic loading factor of claims 9, 15, and 20, the claims
are merely broad, not indefinite. See In re Johnson, 558 F.2d 1008, 1016 n.17
(CCPA 1977) (“[B]readth is not indefiniteness”). In other words, the claims are
not made unclear simply because an upper boundary is not specified. Here, the
claims expressly reach any aerodynamic loading factor having values “greater than
or equal to a value of 0.5,” no matter how large the aerodynamic loading factor
may be. The fact that in the context of the claimed invention there may be
practical upper limits of the claimed range does not impart any indefiniteness as to
the scope of the claim because an upper limit is not explicitly claimed. “A patent
claim to a fishing pole would not be invalid on indefiniteness grounds if it
contained a limitation requiring that the pole be ‘at least three feet long,’ even
though a 50 foot long fishing pole would not be very practical.” Exxon Res. &
Eng’g Co. v. U.S., 265 F.3d 1371, 1382 (Fed. Cir. 2001).
Hence, as the scope of the claims, although it is broad, is nonetheless clear,
we do not sustain the rejection under 35 U.S.C. § 112(b) of claims 9, 15, and 20 as
being indefinite.

Rejection III
Each of independent claims 1 and 11 requires, inter alia, a “trench”
having a width extending “from” an airfoil towards an adjacent airfoil.
Appeal Br. 14, 15 (Claims App.).
Appeal 2019-006780
Application 15/027,562

9

The Examiner finds Staubach discloses a gas turbine engine
component including, inter alia, a trench adjacent suction side 22 of the
component 10, extending from airfoil 14 to an adjacent airfoil 14, and
having a width less than a distance between adjacent airfoils 14. Final Act.
11. The Examiner explains that the trench in Staubach is the portion of
trough 30 located below the dotted line in Staubach’s Figure 2, and which
does not include sections 37 and 38. In order to better illustrate, the
Examiner provides an annotated Figure 2 of Staubach, as shown below:

The Examiner’s annotated Figure 2 of Staubach illustrates a “trench” located
below the dotted line and having a width that does not include portions 37,
38. Id. at 12. In other words, we understand the Examiner’s position to be
that central concave portion 36 of trough 30 in Staubach’s Figure 2
constitutes the claimed “trench.”
Appeal 2019-006780
Application 15/027,562

10

Appellant argues that “Staubach discloses a trough 30 that spans the
entire distance between adjacent airfoils [14]” because trough 30 includes
central concave portion 36 and convex portions 37, 38. Appeal Br. 9
(emphasis added) (citing Staubach, para. 14). According to Appellant, the
Examiner’s arbitrary selection of Staubach’s central concave portion 36 of
trough 30 as the claimed “trench” is merely “an attempt to read on the
language of claim[s] 1” and 11. Reply Br. 3.
In response, the Examiner asserts that the area noted as “trench” in the
above annotated Figure 2 of Staubach “is consistent with the definition of
trench provided by Appellant’s Specification because it is shown . . . to be a
width extending in a lateral direction between two adjacent airfoils.” Ans. 9
(emphasis added) (citing Spec. paras. 5, 45).
We do not agree with the Examiner’s finding that central concave
portion 36 of trough 30 in Staubach’s Figure 2 constitutes a “trench,” as
called for by each of independent claims 1 and 11. In particular, we note
that claims 1 and 11 do not require the trench width to extend between two
adjacent airfoils, as the Examiner asserts, but rather that it extend from an
airfoil to an adjacent airfoil.
Claim language should be read in light of the Specification, as it
would be interpreted by a person of ordinary skill in the art. In re Suitco
Surface, Inc., 603 F.3d 1255, 1260 (Fed. Cir. 2010). Here, an ordinary and
customary usage of the preposition “from” is to indicate “a starting point in
measuring.”10 As such, in each of claims 1 and 11, the trench width starts at
an airfoil and then extends towards an adjacent airfoil. Such a construction

10 See https://www.merriam-webster.com/dictionary/from (last visited June
9, 2020).
Appeal 2019-006780
Application 15/027,562

11

is consistent with Appellant’s Specification, which describes trench 84 as
having “a width 94 that extends from the suction side 72 of the blade 60 and
terminates prior to reaching a pressure side 74 of an adjacent blade 60.”
Spec. para. 47 (emphasis added).
In contrast, the width of Staubach’s central concave portion 36 of
trough 30, which the Examiner equates with the claimed “trench,” does not
start at airfoil 14, but rather somewhere between adjacent airfoils 14, 14.
See Staubach, Fig. 2. Therefore, Staubach’s central concave portion 36 of
trough 30 does not have a width that extends “from” an airfoil to an adjacent
airfoil, as called for by each of independent claims 1 and 11.
Accordingly, as Staubach fails to disclose a “trench” having a width
extending “from” an airfoil towards an adjacent airfoil, we do not sustain the
rejection under 35 U.S.C. § 102(a)(1) of independent claims 1 and 11, and
their respective dependent claims 4–6, 8, 10, 12–14, and 23, as anticipated
by Staubach.

Rejections IV and V
These rejections rely on the same erroneous finding that Staubach
discloses a “trench” having a width extending “from” an airfoil towards an
adjacent airfoil. See Final Act. 17–28. Accordingly, because neither the
Examiner’s modification of Staubach, as per Rejections IV, nor the use of
the disclosure of Bunker, as per Rejection V,11 remedy the deficiency
discussed supra, we also do not sustain Rejections IV and V.

11 Similar to independent claims 1 and 11, independent claim 16 also
requires a “trench” having a width extending “from” an airfoil towards an
adjacent airfoil. Appeal Br. 16 (Claims App.).
Appeal 2019-006780
Application 15/027,562

12

CONCLUSION

Claim(s)
Rejected
35 U.S.C. § Reference(s)/
Basis
Affirmed Reversed
9, 15, 20 112(a) Enablement 9, 15, 20
9, 15, 20 112(b) Indefiniteness 9, 15, 20
1, 4–6, 8,
10–14, 23
102(a)(1) Staubach 1, 4–6, 8, 10–14,
23
9, 13, 15 103 Staubach 9, 13, 15
16–21 103 Bunker,
Staubach
16–21
Overall
Outcome
1, 4–6, 8–21, 23

REVERSED