1112 TOKYO KEISO COMPANY, LTD. and KROHNE MESSTECHNIK GMBH & CO. KG v. SMC CORPORATION and SMC CORPORATION OF AMERICA

NOTE: This disposition is nonprecedential.
United States Court of Appeals for the Federal Circuit
2008-1045, -1112
TOKYO KEISO COMPANY, LTD.
and KROHNE MESSTECHNIK GMBH & CO. KG,
Plaintiffs-Appellants,
v.
SMC CORPORATION
and SMC CORPORATION OF AMERICA,
Defendants,
and
CHRONOTEK SYSTEMS, INC.,
Movants-Appellees.
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TOKYO KEISO COMPANY, LTD.
and KROHNE MESSTECHNIK GMBH & CO. KG,
Plaintiffs-Appellants,
v.
SMC CORPORATION
and SMC CORPORATION OF AMERICA,
Defendants-Appellees.
Michel J. Sacksteder, Fenwick & West LLP, argued for plaintiffs-
appellants. With him on the brief were Darryl M. Woo, David D. Schumann, and
Evan R. Bennett.
Arthur I. Neustadt, Oblon, Spivak, McClelland, Maier & Neustadt, P.C., of
Alexandria, Virginia, argued for defendants-appellees and movants-appellees.
With him on the brief were Thomas J. Fisher and Barry J. Herman. Of counsel
on the brief was Andrew S. Doctoroff, Honigman Miller Schwartz and Cohn LLP,
of Detroit, Michigan.

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2
Appealed from: United States District Court for the Southern District of Texas
Judge David Hittner
Appealed from: United States District Court for the Central District of California
Judge Otis D. Wright

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NOTE: This disposition is nonprecedential.
United States Court of Appeals for the Federal Circuit
2008-1045, -1112
TOKYO KEISO COMPANY, LTD.
and KROHNE MESSTECHNIK GMBH & CO. KG,
Plaintiffs-Appellants,
v.
SMC CORPORATION
and SMC CORPORATION OF AMERICA,
Defendants,
and
CHRONOTEK SYSTEMS, INC.,
Movants-Appellees.
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TOKYO KEISO COMPANY, LTD.
and KROHNE MESSTECHNIK GMBH & CO. KG,
Plaintiffs-Appellants,
v.
SMC CORPORATION
and SMC CORPORATION OF AMERICA,
Defendants-Appellees.

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Appeals from the United States District Court for the Southern District of
Texas in Case No. 07-MC-0279, Judge David Hittner; and from the United
States District Court for the Central District of California in Case No. 06-
CV-374, Judge Otis D. Wright.
____________________________
DECIDED: January 9, 2009
____________________________
Before LOURIE, SCHALL, and PROST, Circuit Judges.
LOURIE, Circuit Judge.
Tokyo Keiso Company, Ltd. and Krohne Messtechnik GMBH & Co. KG
(collectively “Tokyo Keiso”) appeal from the judgment of the United States District Court
for the Central District of California granting summary judgment of invalidity of claims 1,
2, and 5 of U.S. Patent 5,458,004 (“the ’004 patent”). See Tokyo Keiso Co. v. SMC
Corp., 533 F. Supp. 2d 1047 (C.D. Cal. 2007). Tokyo Keiso also appeals from the
judgment of the United States District Court for the Southern District of Texas denying a
motion to compel production of the source code for a product that allegedly infringes the
’004 patent. See In re Chronotek Sys., Misc. No. 07-0279, 2007 U.S. Dist. LEXIS
54661 (S.D. Tex. July 27, 2007). Because the California court did not err in holding
claims 1, 2, and 5 obvious as a matter of law, we affirm.
BACKGROUND
Tokyo Keiso owns the ’004 patent, which is directed to a volume flow meter that
measures the flow volume of fluids passing through a pipe, or measuring line. As
described in the specification, volume flow meters in the prior art measured flow by
using two measuring heads on opposite ends of a length of the measuring line, each
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transmitting an acoustic signal such that one signal moved upstream and the other
moved downstream. The measuring heads measured the difference in time for each
signal to traverse the same distance, allowing the user to determine the speed of the
flow. ’004 patent col.1 ll.36-43. In the prior art, according to the specification, “the
measuring line [was] made of metal, in which the sound velocity is greater than in fluid.”
Id. at col.2 ll.21-22. Thus, the acoustic signal would travel through the metal of the
measuring line faster than it would travel through the fluid, interfering with the
measurement of the signals through the fluid. Id. at col.2 ll.24-35. The ’004 patent
purports to improve upon existing volume flow meters by constructing the measuring
line out of a material that transmits an acoustic signal at a slower sound velocity than
the fluid, such as plastic. Id. at col.2 ll.61-64, col.3 ll.18-22.
In April 2006, Tokyo Keiso sued SMC Corporation and SMC Corporation of
America (collectively “SMC”) for infringement of claims 1, 2, and 5 of the ’004 patent.
Claims 1, 2, and 5 read as follows:
1. A volume flow meter for measuring the flow volume of a fluid by
determining the difference in the travel times of at least two pulsed
acoustic signals, said meter being of the type including a measuring line
(2), a first measuring head (5), and a second measuring head (6), wherein
a first sharp, precisely definable leading edge of the pulsed acoustic signal
transmitted by one of the measuring heads (5,6) is used for the direct time
measurement,
the two acoustic signals are transmitted through the fluid as a measuring
signal as well as through the material of the measuring line (2) as an
interfering signal at least partially interfering with the measuring signal,
and
the measuring line (2) is made of a material that transmits an acoustic
signal at a slower sound velocity than the fluid transmits said signal.
2. The volume flow meter according to claim 1 wherein the measuring line
(2) is of plastic.
2008-1045, -1112 3

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5. In a volume flow meter for measuring the flow volume of a fluid by
determining the difference in the travel times of at least two signals, said
meter being of the type including a measuring line (2), a first measuring
head (5) and a second measuring head (6), the improvement wherein the
measuring line (2) is made of PFA plastic material that transmits an
acoustic signal transmitted by one of the measuring heads (5,6) at a lower
sound velocity than the fluid transmits said signal.
’004 patent col.5 l.2-col.6 l.10.
In May 2007, Tokyo Keiso moved to compel, from non-party Chronotek,
production of Chronotek’s source code, which operates SMC’s accused flow meter.
Tokyo Keiso sought to discover, for the purpose of proving infringement, whether the
source code used the “leading edge of the pulsed acoustic signal” recited in claim 1. In
July 2007, the Texas district court, relying on the findings of a special master, held that
Chronotek only needed to produce the portion of the source code (if any) pertaining to
the use of a threshold amplitude value to detect the arrival of a pulse signal. The court
reasoned that, because the code was a trade secret, Tokyo Keiso had the burden to
show a substantial need for it. The special master had reasoned that any leading edge
would be represented in the code by detection of a threshold amplitude value, so Tokyo
Keiso had shown a substantial need only for that portion of the code.
In October 2007, the California district court held the ’004 patent obvious as a
matter of law. According to the court, U.S. Patent 5,060,507 (“Urmson”) and
Engineering Aspects of Ultrasonic Process Control-Flow, Temperature, and Liquid Level
Applications (“Lynnworth”) would have rendered the invention of the ’004 patent obvious
at the time the invention was made. The Urmson patent discloses a volume flow meter
that uses plastic tubing to prevent sound traveling through the tube from interfering with
a measuring signal flowing through the fluid in the tube. Urmson col.14 ll.34-44. The
Lynnworth article also discloses, in a flow meter, using plastic, and particularly Teflon®,
2008-1045, -1112 4

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pipe to solve the “acoustic short circuit” that results from a metal pipe because “the
longitudinal velocity in Teflon . . . is less than the nominal value for water.” Lynnworth at
67. The court reasoned that both references were within the same field of endeavor as
the ’004 patent, viz., flow meter devices used in industries where accurate
measurement of volume of fluids is necessary. According to the court, both references
would have fairly suggested the same structure and function as the ’004 patent,
including slowing down the interfering signal, and neither teaches away from slowing
down the signal. The court also reasoned that, because the PTO considered neither
Urmson nor Lynnworth during prosecution, the presumption of validity was also much
diminished.
The California district court also reasoned that using PFA plastic, as recited in
claim 5, would have been obvious because both references used plastic, and Lynnworth
used Teflon® in particular. PFA is a member of the Teflon® family. The district court
found that, even if claims 1 and 2 were limited to PTFE plastic based on the
specification, as Tokyo Keiso advocated, PTFE would also have been obvious for the
same reason, i.e., both references disclosed plastic. Thus, according to the court, the
’004 patent’s use of the best type of plastic was a predictable next step to the prior art.
The court also found that the ’004 patent’s use of a straight tube with measuring heads
attached to each side, instead of angularly clamped onto the tube as in the Lynnworth
article, was a predictable next step, and Lynnworth did not teach away from the claimed
invention. Regarding secondary considerations of nonobviousness, the court reasoned
that, even though it took a few years for companies such as Tokyo Keiso to expand on
the prior art, that evidence did not override SMC’s strong showing of obviousness; the
2008-1045, -1112 5

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flow meter business is a small niche market in which only a few players are working to
improve the art.
Tokyo Keiso timely appealed the California district court’s grant of summary
judgment of obviousness and the Texas district court’s denial of its motion to compel
production of the source code. We have jurisdiction pursuant to 28 U.S.C. § 1295(a)(1).
DISCUSSION
We review a district court’s grant of a motion for summary judgment de novo.
Ethicon Endo-Surgery, Inc. v. U.S. Surgical Corp., 149 F.3d 1309, 1315 (Fed. Cir.
1998). Summary judgment is appropriate if “there is no genuine issue as to any
material fact and . . . the moving party is entitled to a judgment as a matter of law.” Fed.
R. Civ. P. 56(c). “The evidence of the nonmovant is to be believed, and all justifiable
inferences are to be drawn in his favor.” Anderson v. Liberty Lobby, Inc., 477 U.S. 242,
255 (1986). “The ultimate judgment of obviousness is a legal determination. Where . . .
the content of the prior art, the scope of the patent claim, and the level of ordinary skill
in the art are not in material dispute, and the obviousness of the claim is apparent in
light of these factors, summary judgment is appropriate.” KSR v. Teleflex, 127 S. Ct.
1727, 1745-46 (2007).
Tokyo Keiso argues that the California district court erred in granting SMC
summary judgment of invalidity of the ’004 patent on the ground of obviousness. Tokyo
Keiso asserts that the court erred in failing to conduct a claim-by-claim analysis, instead
analyzing a non-existent claim that was broader than any of the asserted claims and
finding it obvious.
2008-1045, -1112 6

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Tokyo Keiso also argues that disputed material facts precluded a grant of
summary judgment. For example, Tokyo Keiso’s expert stated that neither the Urmson
patent nor the Lynnworth article recognized the problem of the speed of interfering
signals or use of the claimed materials for controlling speed. Instead, according to
Tokyo Keiso, Lynnworth only mentions acoustic short circuit and low sound speed with
respect to clamp-on flow meters, in which the measuring heads are clamped onto the
outside of the measuring line and transmit a signal transversely across the pipe. Thus,
Tokyo Keiso asserts, a person of ordinary skill in the art would not have applied this
technology to wetted flow meters, in which the measuring heads are immersed in the
fluid and transmit a signal axially with the pipe. Also, according to Tokyo Keiso, the
Urmson patent uses a polymeric material to reduce intensity of sound, rather than
speed, and therefore does not necessarily teach the limitations requiring that the
material transmit sound at a lower speed than fluid. Tokyo Keiso argues that not every
polymeric material reduces the speed that sound travels below that of a fluid, and that
neither Urmson nor Lynnworth discloses using PFA or PTFE.
Tokyo Keiso also asserts that the California district court erred in holding that the
’004 patent was not entitled to the full presumption of validity. According to Tokyo
Keiso, KSR, 127 S. Ct. 1727, does not hold that the presumption is diminished.
Moreover, Tokyo Keiso asserts, the references were cumulative of references that were
cited by the Patent Office. Indeed, according to Tokyo Keiso, the same argument, that
plastic used to match the shear mode velocity rather than lower the sound velocity leads
to the claimed invention, was rejected during prosecution. Finally, Tokyo Keiso asserts
that the court did not properly consider evidence of objective indicia of nonobviousness,
2008-1045, -1112 7

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instead resolving disputes against Tokyo Keiso, the nonmovant. For example,
according to Tokyo Keiso, unrebutted evidence showed a long-felt need and
commercial success.
SMC responds that the California district court addressed every claim limitation
at issue, even if it did not do so in a claim-by-claim analysis. SMC argues that
Lynnworth recognized the problem of the speed of interfering signals and specifically
described the low sound speed of Teflon® as less than the nominal value for water, a
fluid. According to SMC, the Lynnworth article does not teach away from the asserted
claims, as it is not limited to clamp-on meters, and claims 1, 2, and 5 are not limited to
wetted transducers. Indeed, the ’004 patent depicts transducers that transmit signals
through the pipe wall, not wetted transducers. SMC argues that Urmson describes
using plastic to attenuate a sound signal for exactly the same reasons the Lynnworth
article uses plastic, to slow the sound speed, rendering obvious the claim limitation
requiring that the material transmit sound at a lower speed than fluid. SMC also argues
that the ’004 patent specification states that the sound velocity in plastic is less than that
in fluid and that any plastic would be suitable, contrary to Tokyo Keiso’s argument that
not every plastic fits the claim limitations. Moreover, SMC asserts that, with respect to
the specific recitation of PFA in claim 5, the specification describes no additional benefit
from using PFA, and PFA is in the Teflon® family, Teflon® being disclosed in the
Lynnworth article. Thus, according to SMC, Lynnworth would have rendered obvious
the use of PFA in a flow meter.
SMC also argues that the California district court followed KSR, 127 S. Ct. 1727,
as to the presumption of validity because the Patent Office failed to consider the most
2008-1045, -1112 8

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pertinent art. According to SMC, the prior art that the Patent Office considered
disclosed less than Lynnworth disclosed, as Lynnworth described a plastic pipe that
was designed to lower the sound velocity in the pipe compared with the fluid. Finally,
SMC asserts that the court considered the evidence of secondary considerations of
nonobviousness but held that it failed to overcome the strong showing of obviousness.
SMC also argues that it rebutted Tokyo Keiso’s assertion of commercial success.
We agree with SMC that Lynnworth renders claims 1, 2, and 5 of the ’004 patent
obvious, when combined with the admissions in the ’004 patent specification (and
Tokyo Keiso’s admissions as well) that many limitations were in the prior art. Because
we hold the claims obvious based on Lynnworth, we do not address SMC’s arguments
for obviousness based on Urmson.
Tokyo Keiso admits that the ’004 patent specification concedes as prior art most
of the limitations of claims 1, 2, and 5. Claims 1, 2, and 5 recite generally a volume flow
meter that sends two acoustic signals, a measuring line, and two measuring heads. All
of these limitations are thus admittedly in the prior art. The specification describes them
as such. See ’004 patent col.1 l.27-col.2 l.16 (describing these limitations as “in the
state of the art”). “Valid prior art may be created by the admissions of the parties. . . .
[A] statement by an applicant during prosecution identifying certain matter not the work
of the inventor as ‘prior art’ is an admission that the matter is prior art.” Riverwood Int’l
Corp. v. R.A. Jones & Co., 324 F.3d 1346, 1354 (Fed. Cir. 2003) (citations omitted); see
also Constant v. Advanced Micro-Devices Inc., 848 F.2d 1560, 1570 (Fed. Cir. 1988)
(“A statement in a patent that something is in the prior art is binding on the applicant
and patentee for determinations of anticipation and obviousness.”). The only difference
2008-1045, -1112 9

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between flow meters admitted in the specification to be prior art and the invention of
claims 1, 2, and 5 is that the measuring line in the prior art flow meter is made of metal,
whereas the measuring line in the ’004 patent is made of another material. ’004 patent
col.2 l.57-col.3 l.22. Thus, in the claims, the only aspects not admittedly prior art are the
measuring line material that “transmits an acoustic signal at a slower sound velocity
than the fluid transmits said signal” (claim 1), wherein the measuring line material is
plastic (claim 2), and “wherein the measuring line is made of PFA plastic material that
transmits an acoustic signal transmitted by one of the measuring heads at a lower
sound velocity than the fluid transmits said signal” (claim 5).
Lynnworth discloses all of the aspects of claims 1, 2, and 5 that are not
admittedly prior art. Regarding claim 2, Lynnworth discloses a flow meter with “plastic
pipes.” Lynnworth at 67. Lynnworth also recognizes the benefit of a measuring line
made of a material that “transmits an acoustic signal at a slower [or lower] sound
velocity than the fluid transmits said signal,” as required by claims 1 and 5. ’004 patent
cls. 1, 5. Lynnworth states that “[f]low in plastic pipes, including . . . Teflon hose, is
often easier to measure than in metal pipes of the same dimensions because of the
relative absence of acoustic short circuit, and relatively low sound speed in the plastic
pipe.” Lynnworth at 67 (emphasis added). Lynnworth even discloses specific sound
speeds, with the sound speed of Teflon® being slower than that of a fluid: Lynnworth
states that “the longitudinal velocity in Teflon, for example, is ~1350 m/s, which is less
than the nominal value for water, ~1500 m/s.” Id. Similarly, the ’004 patent
specification describes that “[p]lastic is preferably used as the material for the
measuring line, especially PFA. The sound velocity in plastic is in the range of 1,000
2008-1045, -1112 10

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m/s, hence clearly less than the sound velocity of roughly 1,500 m/s for fluids . . . .”
’004 patent col.3 ll.18-22. Thus, Lynnworth, like claims 1 and 5, clearly contemplated
the slower sound velocity of the measuring line material compared with that of the fluid
running through it.
Finally, regarding claim 5, the Lynnworth article would have rendered obvious the
use of PFA as the specific plastic material in the measuring line. As noted above, PFA
is a member of the Teflon® family of plastics, and Lynnworth discloses the use of
Teflon®. Tokyo Keiso presented no evidence that PFA exhibits any unexpected results
in the context of the claimed invention that other Teflon® products do not. See Pfizer,
Inc. v. Apotex, Inc., 480 F.3d 1348, 1371 (Fed. Cir. 2007) (relying on lack of unexpected
results in determining that species claim was obvious in view of prior art genus claim);
In re Woodruff, 919 F.2d 1575, 1578 (Fed. Cir. 1990) (generally requiring applicant, to
defeat obviousness when claiming a subset of a range disclosed in a prior art patent, to
show that “the claimed range achieves unexpected results relative to the prior art
range”). As the ’004 patent specification explains, although PFA is especially preferable
as a material, plastic in general has a sound velocity “less than the sound velocity . . .
for fluids.” ’004 patent col.3 ll.18-22. The specification describes no reason why PFA is
preferable to other members of the Teflon® family. Thus, Lynnworth’s disclosure of the
Teflon® family would have rendered the use of PFA obvious.
We agree with SMC that no material facts regarding Lynnworth’s disclosure were
in dispute that would have precluded summary judgment. Even if, as Tokyo Keiso
argues, some plastics would not reduce acoustic speed below that of a fluid, Lynnworth
2008-1045, -1112 11

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specifically describes Teflon® as having that property, even giving the specific acoustic
speeds of Teflon® and water.
We also agree with SMC that one of ordinary skill in the art would have been
motivated to combine the disclosure of Lynnworth with the admitted prior art described
in the ’004 patent. “When a work is available in one field of endeavor, design incentives
and other market forces can prompt variations of it, either in the same field or a different
one. If a person of ordinary skill can implement a predictable variation, § 103 likely bars
its patentability.” KSR, 127 S. Ct. at 1740. As the California district court found, the
Lynnworth article is “within the same field of endeavor as [the] ’004 [p]atent,” as both
“address[] the problem of acoustic interaction and suggest[] the use of a plastic
measuring line as a solution.” Tokyo Keiso, 533 F. Supp. 2d at 1054, 1056. Tokyo
Keiso argues that Lynnworth teaches away from lowering sound speed in wetted flow
meters and thus teaches away from a combination with the ’004 patent. However,
contrary to Tokyo Keiso’s argument, neither the specification nor claims 1, 2, and 5
apply only to wetted flow meters. Instead, the claims require two measuring heads
located anywhere, and Fig. 1 of the ’004 patent even depicts the measuring heads
outside of the flow. Tokyo Keiso also attempts to rely on an earlier Lynnworth article
that did not relate to an interfering signal to show that Lynnworth was not trying to solve
the problem of interfering signals, thus arguing that Lynnworth was in a different field of
endeavor than the ’004 patent. However, a court need not rely on separate references
to reach a conclusion that the subject matter of asserted claims would have been
obvious based on the plain disclosure of a single reference. Thus, Lynnworth does not
teach away from the claimed combination.
2008-1045, -1112 12

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We also agree with SMC that secondary considerations of nonobviousness do
not overcome the prima facie showing that the Lynnworth article, combined with
admitted prior art, renders claims 1, 2, and 5 of the ’004 patent obvious. Even though
Tokyo Keiso claims to have made out a case of long-felt need and commercial success,
the California district court did not err in finding no genuine issue of material fact
supportive of its case. It stated that, “given the fact that the flow meter business
involves a niche market, it is not surprising that it took a few years for a company to
expand on the prior art at issue here.” Tokyo Keiso, 533 F. Supp. 2d at 1060.
Moreover, the court correctly held that the evidence failed to raise a genuine issue of
material fact sufficient to overcome SMC’s strong showing of obviousness. Id.; see
Leapfrog Enters., Inc. v. Fisher-Price, Inc., 485 F.3d 1157, 1162 (Fed. Cir. 2007)
(“[G]iven the strength of the prima facie obviousness showing, the evidence on
secondary considerations was inadequate to overcome a final conclusion that [the
claim] would have been obvious.”); see also Agrizap, Inc. v. Woodstream Corp., 520
F.3d 1337, 1344 (Fed. Cir. 2008) (same).
The California district court thus did not err in granting summary judgment of
obviousness. “Where . . . the content of the prior art, the scope of the patent claim, and
the level of ordinary skill in the art are not in material dispute, and the obviousness of
the claim is apparent in light of these factors, summary judgment is appropriate.” KSR,
127 S. Ct. at 1745-46. Here, the content of Lynnworth is not in material dispute. As
discussed above, Lynnworth plainly discloses the limitations of claims 1, 2, and 5 that
are not admitted to be in the prior art. The scope of the asserted claims is also not in
material dispute, and obviousness is apparent in light of these factors. We therefore
2008-1045, -1112 13

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2008-1045, -1112 14
affirm the district court and hold as a matter of law that claims 1, 2, and 5 would have
been obvious in view of Lynnworth, combined with the admitted prior art. We have
considered all other arguments raised by Tokyo Keiso and find them unpersuasive.
Because we have affirmed the California district court’s judgment on
obviousness, Tokyo Keiso’s argument regarding the Texas district court’s discovery
decision relating to infringement is moot.
CONCLUSION
Accordingly, the judgment of the district court is affirmed.
AFFIRMED

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