Interference No. 105, 477) THOMAS J. YORKEY v. MOHAMED K. DIAB, ESMAIEL KIANI-AZRBAY JANY, and WALTER M. WEBER

United States Court of Appeals for the Federal Circuit
2008-1578
(Interference No. 105, 477)
THOMAS J. YORKEY,
Appellant,
v.
MOHAMED K. DIAB, ESMAIEL KIANI-AZRBAY JANY,
and WALTER M. WEBER,
Appellees.
Robert C. Morgan, Ropes & Gray LLP, of New York, New York, argued for
appellant. With him on the brief was Marina Len.
Joseph R. Re, Knobbe, Martens, Olson & Bear, LLP, of Irvine, California, argued
for appellees. With him on the brief were Brenton R. Babcock, Irfan A. Lateef and
Jarom D. Kesler.
Appealed from: United States Patent and Trademark Office
Board of Patent Appeals and Interferences

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United States Court of Appeals for the Federal Circuit
2008-1578
(Interference No. 105, 477)
THOMAS J. YORKEY,
Appellant,
v.
MOHAMED K. DIAB, ESMAIEL KIANI-AZRBAY JANY,
and WALTER M. WEBER,
Appellees.
Appeal from the United States Patent and Trademark Office, Board of Patent Appeals
and Interferences.
__________________________
DECIDED: April 7, 2010
__________________________
Before MICHEL, Chief Judge, Gajarsa, Circuit Judge, and Kendall, District Judge1.
MICHEL, Chief Judge.
Appellant Thomas J. Yorkey (“Yorkey”) appeals from a ruling of the Board of
Patent Appeals and Interferences (the “Board”) denying his motion for judgment that
claim 39 of Appellees Mohamed K. Diab, Esmaiel Kiani-Azraby Jany and Walter M.
Weber’s (collectively “Diab”) U.S. Patent Application Ser. No. 09/111,604 (the “Diab
application”) fails to comply with the written description requirement of 35 U.S.C. § 112,
¶ 1. Yorkey also appeals the Board’s denial of his motion for judgment of no
1 Hon. Virginia M. Kendall, U.S. District Court for the Northern District of Illinois, sitting by designation.

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interference-in-fact with respect to Yorkey’s U.S. Patent No. 5,645,060 (the “Yorkey
patent”). We affirm the Board’s rulings.
PROCEDURAL HISTORY
The Yorkey patent and Diab application both claim inventions and methods for
measuring the concentration of oxygen in blood. Yorkey is named as the inventor of the
Yorkey Patent, which issued on July 8, 1997 and was based on U.S. Application Ser.
No. 08/490,315, filed on June 14, 1995. The patent was subsequently assigned to
Nellcor Puritan Bennet, Inc. (“Nellcor”) which is the party in interest. Diab is the named
inventor on the basis of the Diab application filed on July 6, 1998, which claims priority
in turn from U.S. Application Ser. Nos. 08/859,837 (filed May 16, 1997) and 08/320,154
(filed October 7, 1994); the party in interest in the Diab application is Masimo
Corporation of Irvine, California.
An interference (No. 105,477) was declared by the Board on July 18, 2006. The
interference comprised a single count, Count 1, corresponding to claim 6 of the Yorkey
patent and claim 39 of the Diab application. As in the companion interference to this
case, Yorkey was designated the junior party and Diab the senior party. See Yorkey v.
Diab, No. 2008-1577 (hereinafter “Yorkey I”). On June 28, 2007, the Board ruled on two
motions brought by Yorkey, denying both his motion for judgment that claim 39 of the
Diab application fails to comply with the written description requirement of 35 U.S.C. §
112, ¶ 1 (“Motion 1”) and his motion for judgment of no interference-in-fact (“Motion 2”).
The Board subsequently denied Yorkey’s motion for judgment based on priority of
invention and, on May 28, 2008, awarded priority to the Diab application and invalidated
the Yorkey patent. This appeal timely followed.
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BACKGROUND
The technology at issue in this case is medical instrumentation and methods for
the noninvasive measurement of the concentration of oxygen in the blood of a patient
(saturation) and has been described in the companion opinion to this case. Count I of
the interference corresponds to Claim 6 of the Yorkey patent and claim 39 of the Diab
application. Yorkey Claim 6 recites:
A method for measuring saturation of a blood constituent in a patient
comprising the steps of:
. . . .
representing each of said intensity signals as a function of said saturation,
the wavelength corresponding to the intensity signal, and a time-variable
motion term corresponding to motion noise, said motion terms being
proportional to one another for each of said intensity signals; and
solving the three functions to obtain a value for said saturation,
wherein each of said functions includes a plurality of coefficients, and
further comprising the step of determining a set of coefficients for said
third intensity signal from a measurement in the absence of motion noise
and a determination of said saturation from said first and second intensity
signals.
Whereas Diab Claim 39 recites:
A method for measuring saturation of a blood constituent in a patient
comprising the steps of:
. . . .
representing each of said intensity signals as a function of concentration,
the wavelength corresponding to the intensity signal, and a time-variable
motion term corresponding to motion noise, said motion terms being
proportional to one another for each of said intensity signals; and
solving the functions to obtain a value for said saturation,
wherein each of said functions includes a plurality of coefficients related to
the wavelengths, the coefficients of said third function being determined
based upon the coefficients of the first and second functions, and further
comprising the steps of approximating at least a portion of said first and
second intensity signals based upon the third intensity signal, and
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determining said saturation from said approximation of said first and
second intensity signals.
(material variations in text emphasized).
The principal issue of this appeal stems from the last two limitations of each
claim. In the penultimate limitation of its claim 6, the Yorkey patent specifies that “three
functions” (one derived from the signal detected at each wavelength of light emitted by
the sensor probe) are solved to obtain a saturation value, whereas the corresponding
limitation of the Diab application states that “the functions” are solved to obtain a
saturation value.
The final limitations of the respective claims also differ in the language they
employ. The Yorkey patent states that its steps constitute a determination of a set of
coefficients for the third measured intensity signal from a measurement in the absence
of motion noise, and a determination of oxygen saturation from the first and second
intensity signals. The corresponding claim limitation from the Diab application recites
that the coefficient of the third function is determined based upon the coefficients
determined for the first and second signals, and that subsequent steps approximate at
least a portion of the first and second intensity signals based upon the third intensity
signal. The oxygen saturation is subsequently derived from an approximation of the first
and second intensity signals.
DISCUSSION
We have jurisdiction to hear this appeal under 28 U.S.C. § 1295(a)(4)(A) and 35
U.S.C. § 141. See In re Ferguson, 558 F.3d 1359, 1362 (Fed. Cir. 2009).
Because Yorkey’s appeal challenges the Board’s claim construction, we first
address Yorkey’s Motion 2, seeking a judgment of no interference-in-fact. As the junior
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party, Yorkey has the burden of showing, by a preponderance of the evidence, that the
Diab application’s claim 39 and the Yorkey patent’s claim 6 do not interfere-in-fact. See
37 C.F.R. § 41.202(d); In re Garner, 508 F.3d 1376, 1377 (Fed. Cir. 2007).
The standard for determining whether an interference exists is set forth in 37
C.F.R. § 41.203(a):
An interference exists if the subject matter of a claim of one party would, if
prior art, have anticipated or rendered obvious the subject matter of a
claim of the opposing party and vice versa.
Under this standard, Yorkey must prove either that its claims, if prior art, would neither
have anticipated, nor have rendered obvious, the subject matter of Diab’s claim or vice
versa.
Determination that a claim is anticipated under 35 U.S.C. § 102(b) involves two
analytical steps: (1) the Board must interpret the claim language; and (2) the Board
must then compare the construed claim to a prior art reference and make factual
findings that “each and every limitation is found either expressly or inherently in [that]
single prior art reference.” In re Crish, 393 F.3d 1253, 1256 (Fed. Cir. 2004) (quoting
Celeritas Techs. Ltd. v. Rockwell Int'l Corp., 150 F.3d 1354, 1360 (Fed. Cir. 1998)
(alteration in original). We review those factual findings for substantial evidence. In re
Gartside, 203 F.3d 1305, 1315 (Fed. Cir. 2000). Because we find that the asserted
Yorkey patent claim was anticipated by the corresponding claim of the Diab application,
we need not address the question of obviousness.
Moreover, because the PTO, in its claim construction, is entitled to give claims
their broadest reasonable interpretation, our review of the Board's claim construction is
limited to determining only whether the claim construction was reasonable. See 37
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C.F.R. § 41.200(b) (“A claim shall be given its broadest reasonable construction in light
of the specification of the application or patent in which it appears.”); Crish, 393 F.3d at
1256 (“[O]ur review of the Board's claim construction is limited to determining whether it
was reasonable.”).
Both parties agree that the initial issue in this appeal turns upon the Board’s
construction of Diab’s claim 39. Yorkey argued to the Board that the claims at issue
differ because “[c]laim 39 of Diab’s . . . application uses only two functions to obtain
saturation, and recites ‘approximating at least a portion of said first and second intensity
signals based upon the third intensity signal’, whereas claim[ ] 6 . . . of Yorkey’s . . .
patent use[s] all three functions to obtain saturation, and do[es] not approximate a
portion of the first and second intensity signals based upon the third intensity signal.”
Yorkey’s expert witness, Dr. Elvir Causevic (“Causevic”), stated that each of the
three wavelength intensity signals is directly used in the final calculation of saturation by
the use of matrix algebra. Causevic testified that, in contrast, Diab’s claimed invention
obtains the saturation value “based on solving two (not three) functions to calculate its
saturation and using the third wavelength for ‘approximating at least a portion of said
first and second intensity signals based upon the third intensity signal.’”
Diab’s expert, Dr. Gail D. Baura (“Baura”), disagreed that the language of
“solving the three functions” differed from that of “solving the functions.” According to
Baura:
Neither the Yorkey claims, nor the Diab [c]laim include a limitation
requiring that the signals be used without further steps and the functions
be solved together to calculate the saturation directly. The Yorkey claims
recite "solving the three functions to obtain a valued [sic, value] for said
saturation." This limitation does not include a requirement that the signals
be used without further steps and/or the functions be solved together.
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(alterations in original). Baura further disagreed with Causevic that the Diab
application’s claim does not solve the three functions together, but uses the three
functions in a few consecutive calculations. According to Baura:
A person of skill in the art would have knowledge of mathematics and
linear algebra and understand that here there is no substantive difference
between solving three functions together and solving them consecutively.
… It is well known in the art that while matrix algebra can be used to
simplify mathematical calculations, in substance it performs the same task
of solving functions consecutively. In fact, a matrix is simply another way
of writing linear algebraic equations.
With respect to the final pair of limitations commencing with “wherein”, Causevic
testified that in Yorkey’s limitation:
[T]he coefficients of the third wavelength function are determined by taking
measurements in the absence of motion noise and determining saturation
from first and second intensity signals.…These coefficients are then used
when intensity measurements are taken in the presence of motion, and all
three wavelength functions are solved to obtain a value for saturation.
Causevic averred that Diab’s corresponding limitation claimed “something different”
because Diab did not claim a “calibration step” but rather “the ultimate determination of
saturation based on only two wavelengths”, where “the third wavelength is used . . .
solely to generate a reference signal”
Baura disagreed, observing that Causevic’s testimony established that Yorkey’s
claim limitation read on a determination in which the “coefficients of the third wavelength
have to based at least in part on the coefficients of the first and second intensity
functions.” Baura further testified that: “[t]he step of approximating a portion of the first
and second signals is a step in the process of solving the three functions.” Moreover:
[I]t would have been obvious to a person of skill in the art . . . to eliminate
the Diab method of approximating a portion of the first and second signals
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based on the third signal first and using the approximation to calculate the
saturation by putting the functions into a matrix and solving the matrix.…
Thus, a person of ordinary skill in the art having three linear functions
would have found it obvious to go from solving the functions consecutively
to pulling all three in a matrix and solving them together.
The Board found Baura’s testimony to be more credible than that of Causevic
because it was more consistent with the language of the claims. The Board was not
persuaded by Yorkey’s argument that solving the three functions to obtain a value for
oxygen saturation required solving the three functions directly or simultaneously,
observing that Yorkey did not point to any terms in the claims or any description in the
specification that compelled such a narrow construction of its own claims. Such a
narrow construction, held the Board, was not consistent with 37 C.F.R. § 41.200(b)’s
mandate that a claim be given the broadest reasonable construction.
Nor did the Board accept Causevic’s argument that Yorkey’s claims exclude the
Diab application’s approximation step; rather, it accepted Baura’s contention that the
approximation step is simply a step in the solving of the three functions. The Board held
that, rather than exclude such approximation steps, Yorkey’s claim, when properly
construed, embraced them.
On appeal, Yorkey argues the Board erred in assuming a construction of Diab’s
claim 39 that equated “solving the functions to obtain a value for saturation” with
“solving the three functions to obtain a value for saturation.” (emphasis in original).
This is improper, contends Yorkey, because the language of the limitation states that a
saturation value is determined from only two of the signals, with the third one merely
serving as a noise reference to be subtracted. Thus, Diab’s claim 39 cannot be
construed to require “solving the three functions to obtain a value for saturation.”
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According to Yorkey, “such a construction would necessarily require that, regardless of
which functions are solved for saturation, all three must represent a signal as a function
of saturation and be solved as such.”
Yorkey’s argument fails. The specification of the Diab application provides, in
Equations (93), (94), and (95), the three functions derived from each of the three signals
recorded from the probe. Each of these functions is time-dependent, as indicated by
the term Sλn (t) for each function, where n equals one of the three signals, Red1, Red2,
or IR. Factors in each function are εHbO2,λncA , representing the concentration of
oxygenated hemoglobin in the blood, and nλn (t), a noise component. Diab teaches that
each function is solved sequentially to obtain a value for oxygen saturation Thus,
contra Yorkey, all three functions represent a signal as a function of saturation, and the
sequential process of the functions’ solution is necessarily required to obtain a final
value for saturation.
For these reasons, we find that the Board’s denial of Yorkey’s motion for
judgment of no interference-in-fact is supported by substantial evidence, and we
consequently affirm the Board’s decision.
Yorkey next argues that even if the Board correctly construed the language of
Claim 39, there is no written description in the Diab application to support it. The written
description requirement set forth by 35 U.S.C. § 112, ¶ 1 states that:
The specification shall contain a written description of the invention, and of
the manner and process of making and using it, in such full, clear,
concise, and exact terms as to enable any person skilled in the art to
which it pertains, or with which it is most nearly connected, to make and
use the same.
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35 U.S.C. § 112, ¶ 1. Whether the written description requirement is met is a question
of fact. Martek Biosciences Corp. v. Nutrinova, Inc., 579 F.3d 1363, 1369 (Fed. Cir.
2009) (citing Wang Labs., Inc. v. Toshiba Corp., 993 F.2d 858, 865 (Fed. Cir. 1993)).
The test for sufficiency of support in a parent application is whether the disclosure of the
application relied upon “reasonably conveys to the artisan that the inventor had
possession at that time of the later claimed subject matter.” In re Kaslow, 707 F.2d
1366, 1375 (Fed. Cir.1983). This Court will uphold the Board's finding that the Diab
application’s claims are adequately described so long as that finding is supported by
substantial evidence in the record. See Shu-Hui Chen v. Bouchard, 347 F.3d 1299,
1304 (Fed. Cir. 2003).
Yorkey contends that the Diab application does not disclose solving three
intensity signal functions each of which represents a signal as a function of saturation.
Rather, according to Yorkey, the Diab application discloses solving (at most) only two
intensity signal functions to determine a value for oxygen saturation; the third signal is
used merely to generate a noise reference signal that is used to subtract the motion-
induced noise component from the other two remaining signals. The resulting functions
representing those two signals are subsequently solved to yield a value representing
the oxygen saturation.
Yorkey disputes Baura’s expert testimony (with which the Board ultimately
agreed) that the “solving the three functions” limitation is supported because the Diab
application allegedly discloses “using the third wavelength” to generate a reference
signal and therefore the third signal is still used in the ultimate calculation of saturation
Yorkey maintains that the third intensity signal is not represented as a function of
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saturation, and testimony concerning “using” signals did not provide support for a claim
requirement of “solving” three functions, each of which represents a signal as a function
of saturation.
The specification of the Diab application first specifies the emitter and detection
of the third signal at issue:
The third [light-emitting diode (“LED”)] 304 is used to measure a third
signal Sλc (t) to be used to determine saturation using the ratiometric
method. The third LED 304 is time multiplexed with the red and infrared
LED’s [sic] 300 and 302. Thus, a third signal is input to the common
processing circuitry in sequence with the signals from red and infrared
LED’s [sic] 300 and 302.
….
For pulse oximetry measurements using the ratiometric method, the
signals (logarithm converted) transmitted … at each wavelength λa , λb ,
and λc are:
Sλa (t) = Sλred1 (t) = εHbO2 , λa cAHbO2 xA (t) + εHb,λa cAHb xA (t) +
εHbO2 , λa cVHbO2 xV (t) + εHb,λa cVHb xV (t) + nλa(t). (93)
Sλb (t) = Sλred2 (t) = εHbO2 , λb cAHbO2 xA (t) + εHb,λb cAHb xA (t) +
εHbO2 , λb cVHbO2 xV (t) + εHb,λb cVHb xV (t) + nλb(t). (94)
Sλc (t) = SλIR(t) = εHbO2 , λc cAHbO2 xA (t) + εHb,λc cAHb xA (t) +
εHbO2 , λc cVHbO2 xV (t) + εHb,λc cVHb xV (t) + nλc (t). (95) 2
In each equation, the term Sλ(red1), (red 2), or (IR)(t) refers to the function representing
the signal detected from each of the three wavelengths emitted by the probe’s LEDs.
Thus, as a baseline matter, the third signal introduced in this embodiment of the
invention claimed by the Diab application represented by Equation (94) (the Red2 LED
signal) is not merely composed of motion-induced noise, but rather contains
2 Each equation is, of course, a function because the term Sλ(red1) red 2) or (IR)(t) represents
the result of an operation.
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components of both transmitted light representing oxygen saturation (i.e., εHbO2 , λb
c AHbO2 xA (t) + εHb,λb cAHb xA (t) + εHbO2 , λb cVHbO2 xV (t) + + εHb , λb cVHb xV (t) + nλb (t), where
HbO2 represents the concentration of oxygen-bound hemoglobin, Hb represents the
concentration of free hemoglobin, A represents arterial blood, V represents venous
blood and n represents motion-induced noise). This function is, in effect, identical to the
other two functions representing the other two signals detected with the exception of the
varying wavelengths.
The Diab application teaches that the two red wavelengths are selected to satisfy
a proportionality relationship which removes the primary signal portions Sλred1 (t) and
Sλred2(t) yielding a secondary reference, n’(t) by choosing two wavelengths that cause
the primary portions of the measured signals for each to become linearly dependent.
By so choosing, the venous portions likewise become linearly dependent, which allows
removal of these signals, generating the secondary reference signal, n’(t). The signal
so generated can be used in a correlation canceller, such as an adaptive canceller, to
remove the noise portion of the signal.
Claim 39 of the Diab application recites, in relevant part:
[E]ach of said functions includes a plurality of coefficients related to the
wavelengths, the coefficients of said third function being determined
based upon the coefficients of the first and second functions, and further
comprising the steps of approximating at least a portion of said first and
second intensity signals based upon the third intensity signal, and
determining said saturation from said approximation of said first and
second intensity signals.
In the example of the preferred embodiment recited above from the specification,
each function (as represented by Equation (93), (94), and (95)) includes a plurality of
coefficients (both terms relating to Sλred1(t) and Sλred2 (t) as well as to nλn (t)), and the
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2008-1578 13
coefficients of the third function are based upon the coefficients of the first and second
functions (and do not merely represent a pure motion-induced noise coefficient).
Moreover, the recited specification approximates at least a portion of the first and
second intensity signals based upon the third intensity signal (performed by selecting a
wavelength for the third emitted signal that satisfies a proportionality relationship which
removes the primary signal portions Sλred1 (t) and Sλred2(t), yielding a secondary
reference, n’(t), which in turn can be used to refine the relationship between the first and
secondary signals) which in turn yields a value for the oxygen saturation of the blood,
based upon the approximation of the first and second signals so derived.
The language in the limitation thus provides a written description of the limitation
that would reasonably convey to an artisan of ordinary skill that the inventor had
possession at that time of the claimed subject matter. See Lockwood v. Am. Airlines,
Inc., 107 F.3d at 1571-72 (Fed. Cir. 1997). We conclude therefore that there is
substantial evidence supporting the Board’s denial of Yorkey’s Motion 1 that claim 39 of
the Diab application fails to comply with the written description of requirement of 35
U.S.C. § 112, ¶ 1.
CONCLUSION
For the reasons set forth above, we affirm the Board’s denial of both Yorkey’s
motion for a judgment of no interference-in-fact and his motion for judgment that claim
39 of the Diab application fails to comply with the written description of requirement of
35 U.S.C. § 112, ¶ 1.
AFFIRMED

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