  United States Court of Appeals
      for the Federal Circuit
                 __________________________

                   (Serial No. 11/395,232)
           IN RE BLAISE LAURENT MOUTTET
                __________________________

                         2011-1451
                 __________________________

    Appeal from the United States Patent and Trademark
Office, Board of Patent Appeals and Interferences.
               ___________________________

                   Decided: June 26, 2012
                ___________________________

      BLAISE LAURENT MOUTTET, of Arlington, Virginia, pro
se.

    RAYMOND T. CHEN, Solicitor, United States Patent
and Trademark Office, of Alexandria, Virginia, for appel-
lee. With him on the brief were LYNNE E. PETTIGREW and
KRISTI L. R. SAWERT, Associate Solicitors.
               __________________________

      Before PROST, O’MALLEY and REYNA, Circuit Judges.
REYNA, Circuit Judge.

    Mr. Blaise Laurent Mouttet (“Mouttet”) appeals the
decision of the Board of Patent Appeals and Interferences
(“Board”) affirming the rejection of all pending patent
IN RE MOUTTET                                              2


claims under 35 U.S.C. § 103(a). Substantial evidence
supports the Board’s factual determinations, and we
agree with the Board’s conclusion that Mouttet’s claimed
invention would have been obvious to one having ordinary
skill in the art. We therefore affirm.

                     I. BACKGROUND

             A. Mouttet’s Patent Application

     On April 3, 2006, sole inventor Mouttet submitted
utility patent application No. 11/395,232 (“the ’232 appli-
cation”) entitled “Crossbar Arithmetic Processor.” It
discloses a computing device for processes such as addi-
tion, subtraction, multiplication, and division using
nanoscale materials in a crossbar array. 1 Specifically,
Mouttet claimed in representative 2 claim 1:

   1. A computing device comprising:

       at least one crossbar array including a first
   set of N conductive parallel wires (N≥2) forming a
   set of columns and a second set of M conductive
   parallel wires (M≥2) forming a set of rows, and
   formed so as to intersect the first set of conductive
   parallel wires, wherein intersections are formed
   between the first and second sets of wires forming
   MxN crosspoints wherein each of the crosspoints
   is programmable so as to be in a relatively high
   conductive state representative of a binary value 1

   1   Nanoscale materials have dimensions ranging be-
tween 1 and 100 nanometers.
    2  The Board treated Mouttet’s independent claim 1
as representative according to 37 C.F.R. § 41.37(c)(1) and
In re Dance, 160 F.3d 1339, 1340 n.2 (Fed. Cir. 1998).
This decision by the Board is uncontested on appeal.
3                                            IN RE MOUTTET



    or a relatively low conductive state representative
    of a binary value 0;

        a programming unit configured to program
    the crosspoints to have one of the relatively high
    conductive state or the relatively low conductive
    state so that at least one column of the crossbar
    array stores a bit pattern representative of a pro-
    grammed numerical value;

        an input unit configured to provide a bit pat-
    tern representative of an input numerical value to
    the columns of the crossbar array; and

        a post-processing unit configured to convert
    analog signals output from each of the rows of the
    crossbar array into digital output bit patterns and
    configured to combine the digital output bit pat-
    terns so as to form a resultant bit pattern repre-
    sentative of an output numerical value,

        wherein the output numerical value is
    mathematically dependent on both the pro-
    grammed numerical value and the input numeri-
    cal value.

Ex parte Mouttet, No. 2009-010041, 2011 Pat. App. LEXIS
15036, at *1-2 (B.P.A.I. Mar. 29, 2011).

    Mouttet’s crossbar array consists of two intersecting
sets of conductive parallel wires. At the wire junctions, or
“crosspoints,” a thin film material or molecular compo-
nent acts as a bridge between the wires. The resistance of
the thin film material or molecular component between
the intersecting wires may be altered by controlling the
voltages applied to individual wires in the first and sec-
ond sets. By altering the resistance, each crosspoint can
IN RE MOUTTET                                           4


be programmed to be in a high resistance (low conduction)
state or low resistance (high conduction) state. The two
states can represent the binary values “0” and “1” and
thus store digital data. For example, Mouttet’s Figure 2b
from the ’232 application, below, illustrates the internal
structure of a 3x8 crossbar array with various crosspoints
in either state after programming:




Figure 2b depicts binary values 00001001, 00000111, and
00000011, which in the base 10 number system represent
the numerals 9, 7, and 3.

    Mouttet’s claimed computing device adds other input
and output units to the central crossbar array. As shown
in Figure 1 of the ’232 application, reproduced below, an
input unit 103 and a program unit 102 provide the neces-
sary voltage to the array of crossbar wires 101, altering
the resistance at the crosspoints:
5                                            IN RE MOUTTET




By altering the conductive states of the crosspoints, input
unit 103 and program unit 102 provide the crossbar array
with bit patterns (a series of “0”s and “1”s) representative
of numerical values. Post-processing unit 105 converts
the analog signals from each of the rows of the crossbar
array 101 into digital output bit patterns representative
of numerical values, for example, the sum of the values
provided by the input unit 103 and program unit 102.

                       B. Prior Art

   The examiner at the United States Patent and
Trademark Office (“PTO”) rejected all twenty of Mouttet’s
pending claims under § 103(a) as unpatentable over a
publication by Shamik Das 3 (“Das”) and four prior art

    3   Shamik Das, et al., Architectures & Simulations
for Nanoprocessor Systems Integrated on the Molecular
Scale, in Introducing Molecular Electronics 479, ch. 17
(2005), available at http://www.mitre.org/work/tech
papers/tech papers 05/05 0977/05 0977.pdf.
IN RE MOUTTET                                              6


patents: U.S. Patent Nos. 4,633,386 (filed Apr. 6, 1984)
(“Terepin”), 5,249,144 (filed Sept. 29, 1989) (“Falk”);
6,693,821 (filed June 28, 2001) (“Hsu”), and 6,867,996
(filed Aug. 29, 2002) (“Campbell”). The only relevant
references for purposes of this appeal are Falk, Das, and
Terepin. See infra nn. 4 & 5.

                          1. Falk

     Falk, a patent issued September 28, 1993, discloses a
programmable computing device for performing arithme-
tic and logic operations. See Abstract; id. at col.1 ll.7-11.
Falk’s central circuit component consists of a crossbar
array having two intersecting sets of parallel optical
channels, or simply put, crossed paths of light. Id. at col.1
ll.35-39; col.6 ll.39-42. Figure 1 of Falk illustrates an
example of a 4x4 optical crossbar circuit:




                              FIG. 1

In Figure 1, the crossbar array has two sets of inputs. Id.
at col.3 ll.38-51. Input 100 from channel 1 and input 200
from channel 2 are light sources that have been turned on
7                                             IN RE MOUTTET



so as to beam light along optical paths 101 and 201. Id.
at col.3 ll.38-46. The intensity of light at each intersect-
ing region along the crossbar’s optical paths (e.g., 300-
302) represents a particular logic state. Id. at col.1 ll.39-
42; col.3 ll.46-51. The examiner determined, on the basis
of these disclosures, that Falk teaches an optical crossbar
array for its principle arithmetic/logic unit.

   Figure 13 shows the larger computing device that en-
capsulates the optical crossbar array as arithmetic unit
133, id. at col.5 ll.48-51 (“arithmetic unit 133 . . . is im-
plemented as per FIGS. 1-4”):




                          FIG. 13

Falk’s crossbar arithmetic unit 133 receives inputs from
reordering tables 131 and 132. Id. at col.6 ll.39-48.
Inputs from 131 and 132 are configured to send signals
along lines 161-165, providing inputs to crossbar arithme-
tic unit 133 and programming the device to perform the
desired arithmetic operation. Id. at col.5 l.67-col.6 l.46;
IN RE MOUTTET                                              8


col.6 ll.55-61. Crossbar arithmetic unit 133 produces a
set of outputs 170 based on the logic states at the crossbar
intersections. Id. at col.6 ll.46-52. Outputs 170 are
further processed at unit 134 to represent the result of
the arithmetic operation at output 180. Id.

                          2. Das

    Das, a 2005 publication cited by Mouttet in the ’232
application, discloses nanoprocessor systems integrated
on the molecular scale. “By integration on the molecular
scale,” Das explains generally, “we mean the basic switch-
ing devices, as well as the wire widths and the pitch
dimensions (i.e., spacing between the centers of neighbor-
ing wires), all will measure only a few nanometers—the
size of a molecule—in the computer systems of interest
here.” Das at 481.

    Das specifically discloses a nanoscale crossbar array
with molecular switches. Das’s Figure 17.1 depicts struc-
tures of one or a few molecules, sandwiched between
intersecting wires at the junctions of a crossbar array:




 “Fig. 17.1 ‘Crossbar’ array of nanowires with molecular
                  devices at junctions.”
9                                            IN RE MOUTTET



Das at 483. Das explains that the electrical behavior of
the molecular-scale structures at each junction can act as
a switch with two states: a high-conductance “on” state
and a low-conductance “off” state. Id.; see also id. at 484
& fig.17.2. This “allows the ‘programming’ of a junction
into one of two states. Such bistable switches are essen-
tial components of any computing system.” Id. at 483.
On the basis of these disclosures, the examiner deter-
mined that Das teaches molecular switches on a nano-
scale crossbar array capable of being programmed into
high resistance or low resistance states, thereby con-
structing functional circuits that can be used to build
larger processor systems. Id.

                        3. Terepin

    Terepin, a patent issued December 30, 1986, is enti-
tled “Digital Signal Processor.” The examiner determined
that Terepin teaches the use of analog-to-digital (“A/D”)
converter capable of converting analog signals to digital
bit patterns. Terepin, col.3 ll.22-27.

       C. Examiner Rejection and Board Decision

    The examiner found that Falk taught all of Mouttet’s
recited limitations in representative claim 1 except for (1)
a crossbar array implemented with electrical wires rather
than optical light paths, (2) crosspoints with programma-
ble states based on electrical conductivity rather than
optical intensity, and (3) conversion of analog signal
outputs to digital output bit patterns in the post-
processing unit. Ex parte Mouttet, 2011 Pat. App. LEXIS
15036, at *3-4. The examiner relied on Das to teach the
missing crossbar array using wires and crosspoints that
are programmable to have electrical conductive states,
and on Terepin to teach a component converting analog
IN RE MOUTTET                                               10


signals to digital bit patterns. The examiner thus rejected
claims 1, 2, 6-12, and 16-20 of the ’232 application under
35 U.S.C. § 103(a) as obvious over Falk, in view of Das
and Terepin. 4 Mouttet appealed to the Board under 35
U.S.C. § 134(a).

    On March 29, 2011, the Board affirmed the exam-
iner’s rejection of all twenty claims. 5 Ex parte Mouttet,
2011 Pat App. LEXIS 15036, at *1. The Board agreed
that an ordinarily skilled artisan, i.e., an electrical engi-
neer with several years of related industry experience,
would have recognized that substituting Das’s wired
crossbar array for Falk’s optical path crossbar would have
predictably yielded Mouttet’s claimed computing device.
Id. at *6, *9 (citing KSR Int’l Co. v. Teleflex, Inc., 550 U.S.
398, 416 (2007)). The Board found that while Falk notes
certain advantages to optical devices, the reference in no
way suggests that using electronic hardware instead of
optical hardware would destroy Falk’s operability as a
programmable arithmetic unit, nor that it teaches away
from electrical circuitry. Id. at *7. The Board also found
adequate reasons to combine the references because (1) as
taught in Das, electrical circuitry “enable[s] more complex
and specialized functions to be performed,” (2) “combining
these references would predictably yield the claimed
computing device,” and (3) “the relative advantages and

    4   The examiner also rejected claims 3, 4, 13, and 14
under § 103(a) as unpatentable over Falk, Das, Terepin,
and Hsu, as well as rejecting claims 5 and 15 under
§ 103(a) as unpatentable over Falk, Das, Terepin, and
Campbell.
    5   As the rejections of claims 3-5 and 13-15 were not
appealed to the Board by pointing out with particularity
alleged errors in the examiner’s reasoning, the Board
sustained these rejections as well without discussing the
teachings of Hsu and Campbell. These issues are not
before us in this appeal.
11                                           IN RE MOUTTET



disadvantages in selecting electrical circuitry in lieu of
optical circuitry amounts to an engineering tradeoff—a
decision well within the level of ordinarily skilled arti-
sans.” Id. at *8-9. Importantly, the Board noted that
there is no requirement that the examiner show how to
physically incorporate Das’s features into Falk, because
obviousness focuses on what the combined teachings
would have suggested. Id. at *8 (citing In re Keller, 642
F.2d 413, 425 (CCPA 1981)). The Board affirmed the
examiner rejection of all claims in Mouttet’s application
on § 103(a) grounds. Id. at *9-10. Mouttet appealed to
this court, submitting an Overdue Informal Brief of
Appellant on August 5, 2011. 6 We exercise jurisdiction
pursuant to 28 U.S.C. § 1295(a)(4)(A).

                     II. DISCUSSION

                 A. Standard of Review

     Whether an invention would have been obvious to one
of ordinary skill in the art is a legal determination based
on underlying findings of fact. KSR, 550 U.S. at 427; In
re Gartside, 203 F.3d 1305, 1316, 319 (Fed. Cir. 2000)
(citing Graham v. John Deere Co., 383 U.S. 1, 17-18
(1966)). The scope and content of the prior art, as well as
whether the prior art teaches away from the claimed
invention, are determinations of fact. See Para-Ordnance
Mfg., Inc. v. SGS Importers Int’l, Inc., 73 F.3d 1085, 1088
(Fed. Cir. 1995). The PTO bears the initial burden of
showing a prima facie case of obviousness. In re Mayne,
104 F.3d 1339, 1341 (Fed. Cir. 1997). If the PTO carries
its burden, the applicant must rebut the PTO’s showing.
Id.

     6In re Mouttet, No. 2011-1451, 2011 U.S. App.
LEXIS 17401 (Fed. Cir. Aug. 19, 2011).
IN RE MOUTTET                                           12


    While this court reviews the Board’s legal conclusion
of obviousness without deference, it upholds the Board’s
factual findings if supported by substantial evidence. In
re Gartside, 203 F.3d at 1313-16. Substantial evidence is
something less than the weight of the evidence but more
than a mere scintilla of evidence. Id. at 1312 (citing
Consol. Edison Co. v. Nat’l Labor Relations Bd., 305 U.S.
197, 229-30 (1938)). It means such relevant evidence as a
reasonable mind might accept as adequate to support a
conclusion. Consol. Edison, 305 U.S. at 229-30. Thus,
“where two different, inconsistent conclusions may rea-
sonably be drawn from the evidence in record, an agency’s
decision to favor one conclusion over the other is the
epitome of a decision that must be sustained upon review
for substantial evidence.” In re Jolley, 308 F.3d 1317,
1329 (Fed. Cir. 2002); see also Gartside, 203 F.3d at 1312
(noting that the possibility of drawing inconsistent con-
clusions from the evidence does not prevent the Board’s
findings from being supported by substantial evidence).

                       B. Analysis

    A claimed invention is unpatentable “if the differences
between the subject matter sought to be patented and the
prior art are such that the subject matter as a whole
would have been obvious at the time the invention was
made to a person having ordinary skill in the art to which
said subject matter pertains.” 35 U.S.C. § 103(a). Where
“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.” See KSR, 550 U.S.
at 416. A reference may be read for all that it teaches,
including uses beyond its primary purpose. See id. at
418-21; see also Beckman Instruments, Inc. v. LKB Pro-
dukter AB, 892 F.2d 1547, 1551 (Fed. Cir. 1989).
13                                           IN RE MOUTTET



     The government argues on appeal that substantial
evidence supports the factual determinations underlying
the Board’s conclusion that Mouttet’s claimed invention
would have been obvious in view of the combination of
Falk, Das, and Terepin. The ’232 application broadly
claims a computing device comprising a crossbar array of
wires with programmable crosspoints that can be in a
relatively high or relatively low conductive state, pro-
gramming and input units, and a post-processing unit
that converts analog signals to digital signals to output a
numerical value. The Board found that Falk discloses a
computing device with all the recited limitations of Mout-
tet’s representative claim 1 except that Falk lacks an A/D
converter and uses optical paths rather than electrical
wires for the crossbar array. The Board found that Tere-
pin supplied the missing A/D converter and that Das
taught the electrical crossbar array with programmable
crosspoints in relatively high or low conductive states.
The government maintains that a person having ordinary
skill in the art would have implemented Falk’s arithmetic
processor design using Das’s known electrical crossbar
array.

    Mouttet makes two arguments on appeal: first, that
substituting electronic hardware for optical hardware
would destroy the Falk device’s principle of operation and
physical structure; and second, that Falk teaches away
from the claimed invention. Each is addressed below.

     1. Principle of Operation and Physical Structure

    According to Mouttet, the Board erred in finding that
Falk does not suggest that using electronic wires instead
of optical paths would destroy Falk’s ability to operate as
a programmable arithmetic unit. Mouttet argues that
eliminating the optical components from Falk impermis-
IN RE MOUTTET                                           14


sibly destroys its principle of operation. He cites In re
Ratti, 270 F.2d 810, 813 (CCPA 1959), for the proposition
that if the combination of references would change the
principle of operation of the prior art, then the teachings
cannot suffice to render claims obvious.

    We find the Board’s determination that eliminating
the optical components of Falk would not destroy its
principle of operation to be supported by substantial
evidence. As the examiner found, the type of circuitry
used is the main difference between Mouttet’s invention,
which is based on electrical conductivity, and Falk’s
invention, which is based on optical paths. But this
difference does not affect the operability of Mouttet’s
broadly claimed device—a programmable arithmetic
processor. The Board found, and we agree, that the
principle of operation of Falk’s computing device is its
high level ability to receive inputs into a programmable
crossbar array and processing the output to obtain an
arithmetic result. Similarly, Mouttet’s claim 1 operates
by combining Falk, Das, and Terepin to receive inputs
into a programmable crossbar array and processing the
output to obtain an arithmetic result. Stated differently,
the examiner saw nothing in the programming and proc-
essing of junction states in Falk that is unique to its
optical implementation, and Mouttet has not shown
otherwise. Thus, the Board’s determination that the
difference in the circuitry—electrical versus optical—does
not affect the overall principle of operation of a program-
mable arithmetic processor was supported by substantial
evidence. See, e.g., In re Umbarger, 407 F.2d 425, 430-31
(CCPA 1969) (finding Ratti inapplicable where the modi-
fied apparatus will operate “on the same principles as
before”).
15                                            IN RE MOUTTET



    Mouttet further objects that replacing Falk’s optical
crossbar circuitry with Das’s electrical crossbar circuitry
would destroy the physical structure of Falk. Mouttet
argues that there is no evidence that electrical crossbar
circuitry would have been recognized by ordinarily skilled
artisans as equivalent to, or able to be substituted for,
optical crossbar circuitry.

     Any alleged nonequivalence in the type of circuit is ir-
relevant to the Board’s determination since the examiner
did not rely on art-recognized equivalence in substituting
the crossbar arrays. It is well-established that a determi-
nation of obviousness based on teachings from multiple
references does not require an actual, physical substitu-
tion of elements. In re Etter, 756 F.2d 852, 859 (Fed. Cir.
1985) (en banc) (“Etter’s assertions that Azure cannot be
incorporated in Ambrosio are basically irrelevant, the
criterion being not whether the references could be physi-
cally combined but whether the claimed inventions are
rendered obvious by the teachings of the prior art as a
whole.”); 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 Keller, 642 F.2d 413, 425 (CCPA
1981) (“The test for obviousness is not whether the fea-
tures of a secondary reference may be bodily incorporated
into the structure of the primary reference . . . .”).

    Thus, it was not requisite to the Board’s § 103(a) de-
termination that Das’s features be deemed equivalent for
purposes of substitution into Falk’s device. Rather, the
test for obviousness is what the combined teachings of the
references would have suggested to those having ordinary
skill in the art. Id. The Board properly found that an
electrical engineer with several years of related industry
experience would indeed have recognized that Falk’s
IN RE MOUTTET                                             16


arithmetic processor could have been combined with Das’s
wired crossbar array to predictably yield Mouttet’s
claimed computing device. See KSR, 550 U.S. at 416, 421.

    We further note that Mouttet’s objection to substitut-
ing the electrical components of Das into the optical
crossbar array of Falk is based on an incorrect assump-
tion: that, because the Board designated Falk as the “base
reference,” Falk’s optically-based crossbar implementa-
tion—vis-à-vis Das’s electrically-based implementation—
is a controlling principle of operation that any prior art
combination must preserve. But where the relevant
factual inquiries underlying an obviousness determina-
tion are otherwise clear, characterization by the examiner
of prior art as “primary” and “secondary” is merely a
matter of presentation with no legal significance. See In
re Bush, 296 F.2d 491, 496 (CCPA 1961) (Rich, J.); In re
Krammes, 314 F.2d 813, 816-17 (CCPA 1963). While we
recognize that there may be some cases in which relevant
factual determinations inhere in such characterization of
prior art references, this case is not one.

    Here, as found by the Board, Das clearly teaches what
is at the core of Mouttet’s invention: a crossbar of parallel
conductive wires with programmable molecular-scale
switches at the junctions. Das at 483-84. Using Das’s
principles of operation, one skilled in the art readily could
have made a larger computer processor system using
known input, output, and A/D converter units, as taught
in Falk and Terepin. Thus, from either perspective, the
claimed invention would have been obvious under
§ 103(a).
17                                             IN RE MOUTTET



      2. Falk Does Not “Teach Away” from Electrical
                        Circuitry

    Mouttet argues that Falk “teaches away” from the
claimed invention. A reference that properly teaches
away can preclude a determination that the reference
renders a claim obvious. See DePuy Spine, Inc. v. Med-
tronic Sofamor Danek, Inc., 567 F.3d 1314, 1326-27 (Fed.
Cir. 2009). Whether or not a reference teaches away from
a claimed invention is a question of fact. See In re Napier,
55 F.3d 610, 613 (Fed. Cir. 1995).

   To this end, Mouttet relies on the following passage to
suggest that Falk teaches away from electrical circuitry:

     There is a fundamental difference between optical
     circuits, in which the information carriers are
     photons, and electronic circuits, where the carri-
     ers are electrons . . . . [I]n optical devices, there
     exist interconnect possibilities that do not exist
     with electronic hardware, in particular, intercon-
     nected parallel architectures which permit digital
     arithmetic and logic operations to be performed in
     a completely parallel, single step process. After
     the inputs are switched on, the output appears in
     the time it takes a photon to transit the device.
     No faster computation time is possible.

Falk, col.1 ll.12-17.

    In In re Gurley, 27 F.3d 551, 553 (Fed. Cir. 1994), we
emphasized that “[a] reference may be said to teach away
when a person of ordinary skill, upon reading the refer-
ence, would be discouraged from following the path set
out in the reference, or would be led in a direction diver-
gent from the path that was taken by the applicant.”
IN RE MOUTTET                                             18


Thus, the “mere disclosure of alternative designs does not
teach away.” In re Fulton, 391 F.3d 1195, 1201 (Fed. Cir.
2004). This court has further explained that just because
better alternatives exist in the prior art does not mean
that an inferior combination is inapt for obviousness
purposes. Gurley, 27 F.3d at 553.

     The Board determined that the Falk passage Mouttet
recites does not “teach away” from a computing device
using an electrical crossbar array under our law. That
determination is supported by substantial evidence. Falk
indeed recognizes a “fundamental difference” between
circuit types, and even suggests that electrical circuits are
an inferior to optical circuitry for certain purposes. Falk,
col.1 ll.12-17. But the Board found that “even if Falk’s
[sic] discusses a preferred embodiment (e.g., an optical
circuit with more interconnect possibilities), this does not
teach away from a non-preferred embodiment containing
an arithmetic/logic system having electrical circuitry with
wire sets.” March 29, 2011 Board Decision at 6. While
Mouttet’s reading of Falk is plausible, our standard of
review mandates that we uphold factual findings that are
supported by substantial evidence as opposed to revisiting
them de novo.

    As noted by the Board, Mouttet fails to cite any refer-
ence suggesting that the claimed invention would be
unlikely to work using electrical circuitry; he alleges only
that it may be inferior for certain purposes. See id.;
Gurley, 27 F.3d at 553; Baxter Int’l, Inc. v. McGaw, Inc.,
149 F.3d 1321, 1328 (Fed. Cir. 1998) (finding no teaching
away where nothing in the prior art device suggested that
the claimed invention was unlikely to work). In this case,
a known system such as an arithmetic/logic unit “does not
become patentable simply because it has been described
as somewhat inferior to some other product for the same
19                                           IN RE MOUTTET



use,” such as an arithmetic/logic unit having electrical
circuitry despite fewer interconnect possibilities than
optical circuitry. Gurley, 27 F.3d at 553. Nor do we
recognize in Falk any teaching—sufficient to overturn the
contrary determination of the Board—that a crossbar
arithmetic processor “should not” or “cannot” be imple-
mented with electrical circuitry, Para-Ordnance, 73 F.3d
at 1090, or that “criticize[s], discredit[s], or otherwise
discourage[s]” a device like Mouttet’s, In re Fulton, 391
F.3d at 1201.

                     III. CONCLUSION

    We find that the Board’s factual determinations are
supported by substantial evidence, and that it would have
been obvious to persons having ordinary skill in the art to
combine the features of Falk, Das, and Terepin to arrive
at the invention claimed in the ’232 application. The
Board’s decision is therefore affirmed.

                      AFFIRMED

                          COSTS

     No costs.
