Court Opinion

ID: 4162222
Source: CourtListenerOpinion
Date Created: 2017-04-21 15:04:45.684149+00
Date Added: 2024-06-11T14:23:56.680761
License: Public Domain

NOTE: This disposition is nonprecedential.

   United States Court of Appeals
       for the Federal Circuit
                       ______________________

    PAICE LLC, THE ABELL FOUNDATION, INC.,
                   Appellants

                                      v.

                   FORD MOTOR COMPANY,
                            Appellee
                     ______________________

                             2016-1411
                       ______________________

    Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in No. IPR2014-
00570.
    ---------------------------------------------------------------------------

    PAICE LLC, THE ABELL FOUNDATION, INC.,
                   Appellants

                                      v.

                   FORD MOTOR COMPANY,
                            Appellee
                     ______________________

                             2016-2033
                       ______________________
2                         PAICE LLC   v. FORD MOTOR COMPANY

    Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in No. IPR2014-
01415.
                 ______________________

                Decided: April 21, 2017
                ______________________

    RUFFIN B. CORDELL, Fish & Richardson, PC, Washing-
ton, DC, argued for appellants. Also represented by
TIMOTHY W. RIFFE, DANIEL TISHMAN, BRIAN JAMES
LIVEDALEN.

    MATTHEW J. MOORE, Latham & Watkins LLP, Wash-
ington, DC, argued for appellee. Also represented by
GABRIEL BELL; ANDREW B. TURNER, JOHN P. RONDINI,
FRANK A. ANGILERI, SANGEETA G. SHAH, Brooks Kushman
PC, Southfield, MI.
                 ______________________

    Before DYK, MAYER, and TARANTO, Circuit Judges.
TARANTO, Circuit Judge.
    Paice and The Abell Foundation (collectively, Paice)
own U.S. Patent No. 8,214,097 issued to Severinsky,
which describes and claims a control strategy for hybrid
vehicles. Ford Motor Company sought the two inter
partes reviews of the ’097 patent now before us. In one,
the Patent Trial and Appeal Board determined that
claims 1–6, 8–16, 18–26, 28–30, and 34 are unpatentable
for obviousness. Ford Motor Co. v. Paice LLC, No.
IPR2014-01415, 2016 WL 932941 (P.T.A.B. Mar. 10, 2016)
(1415 Decision). In the other, the Board determined that
claims 30–33, 35, 36, and 39 are unpatentable for obvi-
ousness. Ford Motor Co. v. Paice LLC, No. IPR2014-
00570, 2015 WL 5782083 (P.T.A.B. Sept. 28, 2015) (570
Decision). Paice appeals, arguing that the Board miscon-
strued several claim terms and made insufficiently sup-
PAICE LLC   v. FORD MOTOR COMPANY                          3

ported factual findings in arriving at the ultimate obvi-
ousness determinations. We have jurisdiction under 28
U.S.C. § 1295(a)(4)(A). We reject Paice’s arguments and
affirm.
                              I
     For present purposes, a hybrid vehicle is a vehicle
containing an electric motor (and associated battery) and
an internal combustion engine (and associated gasoline or
comparable fuel source). The ’097 patent discloses certain
processes for controlling the vehicle, focused on increasing
fuel efficiency and decreasing emissions. Two features of
the processes are key here: the vehicle’s use of the motor,
the engine, or both for propulsion is determined based on
the vehicle’s instantaneous torque requirements; and the
rate of increase of the engine’s torque output is controlled.
’097 patent, col. 15, lines 38–41; id., col. 19, lines 41–45;
id., col. 38, line 62, through col. 39, line 14. Except as
otherwise noted below, claim 1 is illustrative of the chal-
lenged claims. It states:
    1. A method for controlling a hybrid vehicle, said
    vehicle comprising a battery, a controller, wheels,
    an internal combustion engine and at least one
    electric motor, wherein both the internal combus-
    tion engine and motor are capable of providing
    torque to the wheels of said vehicle, and wherein
    said engine has an inherent maximum rate of in-
    crease of output torque, said method comprising
    the steps of:
        [a] operating the internal combustion en-
        gine of the hybrid vehicle to provide
        torque to operate the vehicle;
        [b] operating said at least one electric mo-
        tor to provide additional torque when the
        amount of torque provided by said engine
4                         PAICE LLC   v. FORD MOTOR COMPANY

       is less than the amount of torque required
       to operate the vehicle; and
       [c] employing said controller to control the
       engine such that a rate of increase of out-
       put torque of the engine is limited to less
       than said inherent maximum rate of in-
       crease of output torque, and wherein said
       step of controlling the engine such that
       the rate of increase of output torque of the
       engine is limited is performed such that
       combustion of fuel within the engine oc-
       curs at a substantially stoichiometric ra-
       tio; and comprising the further steps of:
       [d] operating said internal combustion en-
       gine to provide torque to the hybrid vehi-
       cle when the torque required to operate
       the hybrid vehicle is between a setpoint
       SP and a maximum torque output (MTO)
       of the engine, wherein the engine is oper-
       able to efficiently produce torque above
       SP, and wherein SP is substantially less
       than MTO;
       [e] operating both the at least one electric
       motor and the engine to provide torque to
       the hybrid vehicle when the torque re-
       quired to operate the hybrid vehicle is
       more than MTO; and
       [f] operating the at least one electric motor
       to provide torque to the hybrid vehicle
       when the torque required to operate the
       hybrid vehicle is less than SP.
’097 patent, col. 56, line 47, through col. 57, line 15
(bracketed letters added).
PAICE LLC   v. FORD MOTOR COMPANY                        5

                             II
    In construing the claims at issue, the Board permissi-
bly applied the broadest-reasonable-interpretation stand-
ard, and because there are no underlying factual issues
here, we review the Board’s constructions de novo, consid-
ering the usual intrinsic sources of claim meaning, e.g.,
the claims, the specification, and the prosecution history.
See D’Agostino v. MasterCard Int’l Inc., 844 F.3d 945, 948
(Fed. Cir. 2016).
    Paice argues that the Board erred in construing “set-
point” (in elements [d]–[f]) to mean a “predetermined
torque value that may or may not be reset.” 1415 Deci-
sion at *4. We recently affirmed the same construction of
“setpoint” by the Board in a related IPR proceeding in-
volving another Paice patent in the same family as the
’097 patent. Paice LLC v. Ford Motor Co., Nos. 16-1412, -
1415, -1745, 2017 WL 900062, at *3 (Fed. Cir. Mar. 7,
2017). Given the relationship of the patents, we affirm
the Board’s construction here as well.
     Paice also argues that the Board incorrectly read the
first group of claim elements, particularly [b] and [c], as
“unrelated requirements” rather than requiring “a coordi-
nated control strategy whereby the controller limits the
rate of increase of the gas engine’s output torque allowing
the gas engine to burn fuel at a substantially stoichio-
metric ratio, while at the same time, the controller con-
trols the electric motor to provide the shortfall in torque
required for propelling the vehicle.” Appellant’s Br. 32.
According to Paice, the Board implicitly rejected its con-
struction when it found that a key prior-art reference—an
earlier patent issued to Severinsky, U.S. Patent No.
5,343,970—discloses the [b] element, concerning the
motor’s providing additional torque, in its disclosure of
activating the electric motor “when torque in excess of the
capabilities of engine 40 is required.” 1415 Decision at *7
(quoting Severinsky, col. 14, lines 17–18).
6                         PAICE LLC   v. FORD MOTOR COMPANY

    But neither the language of claim 1 nor the language
of the other claims at issue requires the simultaneous
control urged by Paice so as to make the Board’s reading
incorrect under the broadest-reasonable-interpretation
standard. Claim 1 requires the step of “operating said at
least one electric motor to provide additional torque when
the amount of torque provided by said engine is less than
the amount of torque required to operate the vehicle” and
the separate step of “employing said controller to control
the engine such that a rate of increase of output torque of
the engine is limited.” ’097 patent, col. 56, lines 56–61.
That claim language does not require the Board to con-
clude that the two steps, one involving the electric motor
and one involving the gas engine, must occur at the same
time. The other independent claims at issue, claims 11,
21, and 30, do not add anything to change that conclusion.
Nor do the specification or prosecution-history passages
cited by Paice. 1
                            III
    “We review the Board’s ultimate determination of ob-
viousness de novo and its underlying factual determina-
tions for substantial evidence.” Personal Web Techs., LLC
v. Apple, Inc., 848 F.3d 987, 991 (Fed. Cir. 2017). The
factual determinations “include findings as to the scope
and content of the prior art, the differences between the
prior art and the claimed invention, the level of ordinary
skill in the art, the presence or absence of a motivation to
combine or modify with a reasonable expectation of suc-
cess, and objective indicia of non-obviousness.” Ariosa
Diagnostics v. Verinata Health, Inc., 805 F.3d 1359, 1364
(Fed. Cir. 2015). Paice’s challenges on appeal ultimately
focus on various factual findings.

    1   Given our conclusion, we need not address Ford’s
argument that Paice failed to preserve its present simul-
taneity argument.
PAICE LLC   v. FORD MOTOR COMPANY                        7

                             A
    The Board determined that claims 1, 2, 5, 6, 8–12, 15,
16, 18–22, 25, 26, 28, and 29 would have been obvious
over a combination of the Severinsky and Anderson
references. 2 We reject Paice’s challenges.
    In challenging that determination, Paice first focuses
on claim elements exemplified by claim 1’s requirement of
“operating said internal combustion engine to provide
torque to the hybrid vehicle when the torque required to
operate the hybrid vehicle is between a setpoint SP and a
maximum torque output (MTO) of the engine.” ’097
patent, col. 57, lines 1–4. Paice argues that substantial
evidence does not support the Board’s finding that Sever-
insky discloses that element in disclosing the comparison
of the torque required to operate the hybrid vehicle to a
setpoint in order to determine when to operate the engine
versus the electric motor.
    This court’s March 2017 opinion affirmed a Board de-
termination that Severinsky discloses a claim element, in
another Paice patent, that is not materially different from
the setpoint claim element at issue here. Paice, 2017 WL
900062, at *6–7. Paice argues for a different result here
on the ground that the March opinion relied upon evi-
dence, from the Paice patent there at issue, not consid-
ered by the Board in the current case. See Letter from
Appellants to Clarify Issues in Pending Appeals, ECF No.
56. In the March opinion, this court concluded that the
Board had incorrectly “reinterpret[ed] . . . ‘road load’ as
including output torque” rather than input torque (i.e.,
the torque required to propel the vehicle), but the court

   2   “Anderson” is shorthand for Catherine Anderson
& Erin Pettit, The Effects of APU Characteristics on the
Design of Hybrid Control Strategies for Hybrid Electric
Vehicles, SAE Technical Paper 950493 (1995).
8                         PAICE LLC   v. FORD MOTOR COMPANY

nonetheless affirmed the Board’s finding. Paice, 2017 WL
900062, at *7. Passages in the Paice patent there at
issue, the court concluded, themselves indicated that the
prior-art Severinsky taught making the operating-mode
decision based on the torque required to propel the vehicle
(input torque). Id. The same result is required in this
case, because the Board’s decision here is supported by
substantial evidence independent of any passages from
the patent at issue in the March opinion.
     As the Board noted, Severinsky discloses operating
the engine “only under the most efficient conditions of
output power and speed. When the engine can be used
efficiently to drive the vehicle forward, e.g. in highway
cruising, it is so employed.” Severinsky, col. 7, lines 8–13
(emphasis added). Severinsky adds that, in determining
whether the engine is operating under its most efficient
conditions, the controller considers the vehicle’s propul-
sion requirements: “at all times the microprocessor 48
may determine the load (if any) to be provided to the
engine by the motor, responsive to the load imposed by the
vehicle’s propulsion requirements, so that the engine 40
can be operated in its most fuel efficient operating range.”
Id., col. 17, lines 11–15 (emphasis added). Severinsky
further states that the microprocessor runs the engine
“only in the near vicinity of its most efficient operational
point, that is, such that it produces 60–90% of its maxi-
mum torque whenever operated.” Id., col. 20, lines 63–67.
The Board found the lower limit of this range—60% of the
maximum torque output—to be a setpoint that is a pa-
rameter for determining the operating mode. On this
record, the Board had substantial evidence to find that
Severinsky discloses comparing the amount of torque
required to propel the vehicle to a predetermined torque
value in deciding whether to operate the engine.
    Paice also challenges the Board’s reliance on a combi-
nation of Severinsky and Anderson to meet the claim
requirement that the engine’s rate of increase of output
PAICE LLC   v. FORD MOTOR COMPANY                         9

torque is limited to maintain substantially stoichiometric
combustion. 3 Paice argues that a person of ordinary skill
in the art would not have had a motivation to combine the
references and that the combination would not have
worked. The Board did and properly could find otherwise.
    Regarding a motivation to combine, the Board found
that “a skilled artisan would have been led to combine the
basic hybrid control strategy of Severinsky with the
known technique of slowing the engine transient [to
maintain substantially stoichiometric combustion 4], as
taught by Anderson, because both references share the
same fundamental goals of reducing carbon emissions by
maintaining a stoichiometric air-to-fuel ratio.”        1415
Decision at *13. Severinsky refers clearly to the aim of
reducing carbon emissions, Severinsky, col. 12, lines 13–
33, specifically by limiting the supply of air to the engine
to only “slightly in excess of the amount required for
stoichiometric combustion,” id., col. 12, lines 16–17.
Experts from both parties testified that, as a result of
regulatory standards related to emissions, a person of
skill in the art would have been focused on a stoichio-
metric strategy. The Board thus had substantial evidence

   3     Evidence that the Board could credit states that
stoichiometric combustion occurs “when there is just
enough oxygen [in the engine] for conversion of all of the
fuel,” with no excess fuel or air. J.A. 188 ¶ 69. (Except
where otherwise noted, citations to the Joint Appendix
refer to the appendix filed in Appeal No. 2016-2033.)
     4   Evidence that the Board could credit indicates
that “a transient response refers to the response of a
system to a change in its equilibrium as a result of specif-
ic, transient input,” J.A. 194 ¶ 81, and that, in this con-
text, “transient” refers to a change in the torque, power,
or speed output of an engine following changes in driver
demand, id. ¶ 82.
10                        PAICE LLC   v. FORD MOTOR COMPANY

for its finding that a person of skill in the art seeking to
reduce emissions would have been motivated to combine
the teachings of Severinsky with those of Anderson. See
KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 420 (2007)
(“[A]ny need or problem known in the field of endeavor at
the time of invention and addressed by the patent can
provide a reason for combining the elements in the man-
ner claimed.”).
    The Board also had sufficient evidence to reject
Paice’s contention that the Severinsky-Anderson combi-
nation would not have worked. See 1415 Decision at *13–
15. According to Paice, Anderson teaches that slow
transients are possible only with series hybrids, not with
parallel hybrids, which is the type of hybrid disclosed in
the ’097 patent. The Board could find otherwise.
    According to the evidence, in a series hybrid, the en-
gine-motor-wheels arrangement means that only the
motor, not the engine, is mechanically coupled to the
wheels and so only the motor, not the engine, directly
propels the vehicle; the engine supplies power for the
electric motor. In a parallel hybrid, both the engine and
motor are mechanically coupled to the wheels, so each by
itself can directly propel the vehicle. The key passage of
Anderson relied on by Paice is one describing a control
strategy, “the mode a parallel hybrid vehicle always uses,”
in which the engine must “follow the actual wheel power
whenever possible (similar to a conventional automobile)”
and, accordingly, must “perform fast power transients.”
Anderson at 67.
    The Board was not required to give that passage the
reading Paice gives it. Anderson describes that control
strategy as an example of an “extreme” strategy on the
“spectrum of control strategies,” and as not “the optimum
strategy.” Id. Earlier, Anderson says that its teachings
related to the optimum strategy are not limited to series
hybrids: after explaining the differences between series
PAICE LLC   v. FORD MOTOR COMPANY                        11

and parallel hybrids, Anderson states that “[t]he thought
processes presented in this paper are sufficiently general
that they can be applied to any type of vehicle.” Id. at 66.
And later, after explaining that fast transients cause
increased emissions, Anderson states that “[s]ome of this
effect can be reduced using a hybrid strategy that only
allows slow transients.” Id. at 69. That passage, which is
not in terms limited to series hybrids (when the very next
sentence, beginning a new paragraph, is so limited), can
be read as being of general application to hybrids. On
this evidence, we cannot say that substantial evidence is
lacking for the Board’s reading of Anderson as disclosing
the avoidance of fast transients in parallel hybrids.
    Paice further argues that even if the teachings of Sev-
erinsky and Anderson were properly combined, the refer-
ences do not disclose limiting the rate of increase of the
engine’s output torque to less than the inherent maxi-
mum rate of increase of output torque to maintain sub-
stantially stoichiometric combustion. But the Board
found that Severinsky teaches limiting the rate of in-
crease of the engine’s output torque by controlling the
rate of fuel supply to the engine and, together with An-
derson’s slow-transients teaching, would have suggested
limiting the output torque increase to less than the en-
gine’s maximum rate of increase. 1415 Decision at *7–9.
The evidence cited by the Board supports that finding.
                             B
    In the 2014-1415 IPR, Ford separately challenged
claims 3, 13, and 33 as unpatentable for obviousness over
Severinsky, Anderson, and U.S. Patent No. 5,865,263 to
12                        PAICE LLC   v. FORD MOTOR COMPANY

Yamaguchi. The Board agreed with Ford. We affirm that
determination. 5
    These dependent claims contain the additional re-
quirement that “the engine is heated prior to supply of
fuel for starting the engine.” E.g., ’097 patent, col. 57,
lines 22–23. The Board found that Yamaguchi “discloses
rotating an engine to 600 rpm before starting it, and then
starting the engine once it reaches a predetermined
temperature.” 1415 Decision at *15. Paice does not
dispute that finding. Rather, Paice argues that a person
of ordinary skill in the art would not have been motivated
to combine Severinsky, Anderson, and Yamaguchi be-
cause Severinsky expressly teaches operating the engine
at lower temperatures to decrease nitrogen oxide emis-
sions.
    Severinsky states that “the engine 40 will be operated
in lean burn mode” and that “the engine will be operated
at a lower temperature” to reduce nitrogen oxide emis-
sions that result from operating in that mode. Severin-
sky, col. 12, lines 14–20. But the Board found that this
disclosure referred to maintaining a low operating tem-
perature, not a low starting temperature. 1415 Decision
at *15. Substantial evidence supports that finding. The
language in Severinsky speaks of the temperature at
which “the engine will be operated.” And operating at a
“lower temperature” does not necessarily discourage
preheating the engine: Ford’s expert testified that a
lower temperature is not needed to reduce nitrogen oxide
emissions when starting the engine because even when
the engine is warmed before being started, it is likely
significantly cooler than it is during normal engine opera-
tion. J.A. 4031–32 ¶ 82. Therefore, the Board’s finding of

     5  We also affirm the Board’s materially indistin-
guishable determination of obviousness of claims 32 and
33 in the 2014-570 IPR.
PAICE LLC   v. FORD MOTOR COMPANY                           13

a motivation to combine was supported by substantial
evidence.
                              C
    Dependent claims 4, 14, and 24, which depend on
claims 3, 13, and 23, respectively, add the requirement of
“a fuel:air ratio of no more than 1.2 of the stoichiometric
ratio for starting the engine.” E.g., ’097 patent, col. 57,
lines 25–26. The Board determined that the Takaoka
prior-art reference 6 discloses this additional limitation
and on that basis found unpatentability. 1415 Decision at
*16–17. We affirm that determination.
     Substantial evidence supports the Board’s finding
about Takaoka and the claim element at issue. Takaoka
proposes an engine that “would operate with λ = 1 over its
entire range.” Takaoka at 54. Ford’s expert provided
undisputed testimony that “[a] person of ordinary skill in
the art knows that a lambda value of 1 (λ = 1) corresponds
[to] a[n] air:fuel ratio of 1.0 of the stoichiometric ratio.”
J.A. 434 ¶ 603. As Ford’s expert explained, “[a] stoichio-
metric ratio refers to the ideal quantity . . . of one reactant
to completely react with the other reactant in a chemical
reaction such that there are no leftover reactants after the
reaction takes place.”         J.A. 187 ¶ 67.       And “[t]he
fuel[:]air . . . ratio is the inverse of the [air:fuel] ratio.”
J.A. 188 ¶ 69. Accordingly, Takaoka’s air:fuel ratio of 1.0
is a fuel:air ratio of 1.0 of the stoichiometric ratio, and
given that the Board could credit the expert declaration
that “the entire range” covered the starting of the engine,
see J.A. 4033 ¶ 84, the Board properly found the claim
limitation met.

    6  “Takaoka” is shorthand for Toshifumi Takaoka et
al., A High-Expansion-Ratio Gasoline Engine for the
TOYOTA Hybrid System, 47 Technical Rev. 53 (1998).
14                       PAICE LLC   v. FORD MOTOR COMPANY

                            D
     The Board determined that claims 30 and 34 are un-
patentable for obviousness over Severinsky and Takaoka.
1415 Decision at *17–18. Paice challenges the determina-
tion by disputing the motivation to combine Severinsky
and Takaoka and also the Board’s reading of Takaoka as
disclosing limiting the rate of change of torque produced
by the engine so that fuel combustion occurs at a substan-
tially stoichiometric ratio. We reject the challenge. 7
    Paice contends that the Board’s rationale for combin-
ing Severinsky and Takaoka was insufficiently supported.
The Board found that a person of ordinary skill in the art
would have been motivated to combine these references
because they are both “concerned with improving fuel
economy and reducing emissions in hybrid vehicles.”
1415 Decision at *18. In reaching this finding, the Board
adopted as its own Ford’s reasoning regarding a motiva-
tion to combine, id., which included argument and evi-
dence that “’[m]aximum fuel efficiency’ requires complete
combustion of the fuel, which can only be achieved if the
engine is operating at a substantially stoichiometric
ratio.” J.A. 152 (citing J.A. 470 (expert testimony)). As
discussed in the previous section, Takaoka was concerned
with a potential solution for achieving substantially
stoichiometric combustion. And Ford’s expert testified
that implementing Takaoka’s control strategy would
require nothing more than altering an algorithm. In sum:
both references involved the problems of reducing emis-
sions in hybrid vehicles and maximizing fuel efficiency,
Takaoka disclosed a potential solution, and there is

     7  Paice also argues that the combined references do
not teach the controller limitations under its proposed
construction related to certain steps being performed
simultaneously. Because Paice’s proposed construction is
incorrect, we need not consider that argument.
PAICE LLC   v. FORD MOTOR COMPANY                         15

evidence suggesting that Takaoka’s solution was relative-
ly simple to implement. That is enough.
    Paice also contends that Takaoka fails to disclose a
controller that limits the rate of change of torque pro-
duced so that fuel combustion occurs at a substantially
stoichiometric ratio, arguing that Takaoka discloses an
engine design, not a hybrid-control strategy. The Board
disagreed, finding that “Takaoka discloses expressly a
control scheme for lowering the emission levels of the
engine.” 1415 Decision at *17. That finding is supported
by substantial evidence. Although Takaoka does disclose
a “newly developed gasoline engine,” Takaoka at 53, that
disclosure hardly precludes a finding that Takaoka also
discloses achieving the stated goals through use of a
control strategy. And Takaoka in fact repeatedly discuss-
es controlling the engine. See, e.g., id. at 57 (“[T]he en-
gine is controlled so that the intake valve closing is
advanced when the load requirements are high.”); id. at
58 (“By allocating a portion of the load to the electric
motor, the system is able to reduce engine load fluctua-
tion under conditions such as rapid acceleration.”); id. at
60 (“Emissions levels much lower than the current stand-
ard values were attained by optimum control of the motor
and engine.”). It was reasonable for the Board to find that
Takaoka discloses a control strategy for limiting engine
torque, particularly where it credited Ford’s expert testi-
mony that “a mechanical component alone (e.g., an en-
gine) is not capable of such control.” 1415 Decision at *17
(quoting J.A. 4042).
                             E
    In the 2014-570 IPR, the Board determined that de-
pendent claim 33 would have been obvious. Claim 33
requires that the “fuel and air are supplied to said engine
at a fuel:air ratio of no more than 1.2 of the stoichiometric
ratio for starting the engine.” ’097 patent, col. 60, lines
36–38. Paice challenges the obviousness ruling on the
16                          PAICE LLC   v. FORD MOTOR COMPANY

ground that U.S. Patent No. 4,707,984 to Katsuno, which
the Board relied on to disclose this additional limitation,
teaches an air:fuel correction amount, not an actual
air:fuel ratio for starting the engine. We reject the chal-
lenge.
     According to Paice’s expert, “Katsuno describes an
air[:]fuel ratio correction routine that adjusts the air[:]fuel
ratio via an air[:]fuel ratio correction amount . . . based on
information received from . . . air ratio sensors.” Appeal
No. 2016-1411, J.A. 3771 ¶ 125. An air:fuel correction
amount is allegedly different from an actual air:fuel
ratio—the air:fuel ratio correction amount is a “correction
factor by which the air[:]fuel ratio is adjusted towards a
stoichiometric ratio.” Id. The Board did not dispute that
Katsuno discloses an air:fuel correction ratio. Instead, in
finding that Katsuno discloses an air-fuel ratio of no more
than 1.2 of the stoichiometric ratio, the Board relied on
expert testimony that the 1.2 air:fuel correction ratio
disclosed in Katsuno “correlates to a 1.2 fuel:air ratio.”
570 Decision at *10 (quoting J.A. 3852–53).
    The Board-cited testimony is supported by Katsuno
itself. Katsuno refers to the air:fuel correction ratio as
FAF1, see Katsuno, col. 5, lines 36–37, and states that
“FAF1 is guarded by a minimum value 0.8 . . . and by a
maximum value 1.2 . . . , thereby also preventing the
controlled air[:]fuel ratio from becoming overrich or
overlean,” id., col. 7, lines 1–5. This suggests that a FAF1
value of 1.0 would not be “overrich” or “overlean.” And
the reference teaches that whether or not the air:fuel
ratio is too rich or too lean is in relation to the stoichio-
metric air:fuel ratio, see id., col. 6, lines 9–12, so it is
reasonable to infer that a FAF1 value of 1.0 would corre-
late with a mixture of air and fuel that results in stoichi-
ometric combustion—an air:fuel ratio of 1.0 of the
stoichiometric ratio. As previously discussed with respect
to claims 4, 14, and 24, that air:fuel ratio comes within
PAICE LLC   v. FORD MOTOR COMPANY                         17

claim language calling for a fuel:air ratio of no more than
1.2 of the stoichiometric ratio.
     Paice argues that, nevertheless, Katsuno does not dis-
close a fuel:air ratio of no more than 1.2 of the stoichio-
metric ratio when starting the engine. According to Paice,
FAF1 is set at 1.0 during engine starting. See Katsuno,
col. 5, lines 40–44, 61–63. But Paice provides no basis for
overturning the Board’s finding that a FAF1 value of 1.0
correlates with a fuel:air ratio of 1.0 of the stoichiometric
ratio. We conclude that Paice has failed to show that the
Board lacked substantial evidence for its obviousness
determination as to claim 33.
                             IV
    For the foregoing reasons, we affirm the Board’s final
written decisions.
                        AFFIRMED