## United States Court of Appeals for the Federal Circuit

2008-1578 (Interference No. 105, 477)

THOMAS J. YORKEY, Appellant,

v.

MOHAMED K. DIAB, ESMAI EL 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, LL P, 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

## United States Court of Appeals for the Federal Circuit

2008-1578 (Interference No. 105, 477)

THOMAS J. YORKEY, Appellant,

v. MOHAMED K. DIAB, ESMAI EL 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 Judge 1

. MICHEL, Chief Judge. Appellant Thomas J. Yorkey (“Yorkey ”) appeals from a ruling of the Board of Patent Appeals and Interferenc es (the “Board”) denying his motion for judgment that claim 39 of Appellees Mohamed K. Diab, Es maiel Kiani-Azraby J any 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 Illi nois, sitting by designation.interference-in-fact with respect to Yorkey’s U.S. Patent No. 5,645,060 (the “Yorkey patent”). We affirm t he Board’s rulings. PROCEDURAL HISTORY The Yorkey patent and Diab application both claim in ventions 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 wa s subsequently assigned to Nellcor Puritan Bennet, Inc. (“Nellcor”) which is the party in interes t. 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 intere st in the Diab application is Masimo Corporation of Ir vine, California. An interference (No. 105,477) was declar ed 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 Di ab application. As in the co mpanion interference to this case, Yorkey was designated the junior party and Diab t he 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 mo tion for judgment that claim 39 of the Diab application fails to comply with the wri tten description requirem ent 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 mo tion 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.

2008-1578 2BACKGROUND The technology at issue in this case is medical instrumentation and methods for the noninvasive measurement of the concentra tion of oxygen in the blood of a patient (saturation) and has been descri bed 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 sa id 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 inclu des a plurality of coefficients, and further comprising the step of determining a set of coefficients for said third intensity signal from a measurem ent in the absence of motion noise and a determination of said saturation fr om 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 int ensity 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 in cludes 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 por tion of said first and second intensity signals based upon the third intensity signal, and

2008-1578 3determining 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 limit ation of its claim 6, the Yorkey patent specifie s that “three functions” (one derived from t he signal detected at each wavele ngth of light emitted by the sensor probe) are solved to obtain a saturation value, whereas the corresponding limitation of the Diab applicat ion states that “the functi ons” are solved to obtain a saturation value. The final limitations of the respective claims also differ in the language they employ. The Yorkey patent stat es 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 determi nation of oxygen saturation from the first and second intensity signals. The corresponding claim lim itation from the Di ab application recites that the coefficient of the third function is dete rmined based upon the coefficients determined for the first and second signals, and that subsequent st eps approximate at least a portion of the first and second intens ity 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, seek ing a judgment of no interferenc e-in-fact. As the junior

2008-1578 4party, Yorkey has the burden of showing, by a preponderance of the evidence, that the Diab application’s claim 39 and the Yorkey pat ent’s claim 6 do not interfere-in-fact. See 37 C.F.R. § 41.202(d); In re Garner , 508 F.3d 1376, 1377 (F ed. Cir. 2007). The standard for determining whether an interference exis ts is set forth in 37 C.F.R. § 41.203(a): An interference exists if the subject ma tter of a claim of one party would, if prior art, have anticipated or render ed 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 hav e rendered obvious, the subject ma tter 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 interp ret the claim language; and (2) the Board must then compare the constr ued claim to a prior art re ference and make factual findings that “each and every lim itation is found either expre ssly 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). Be cause 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 cons truction, is entitled to give claims their broadest reasonable interpretation, our revi ew of the Board's claim construction is limited to determining only whether the claim construction was reasonable. See 37

2008-1578 5C.F.R. § 41.200(b) (“A claim shall be given its broadest reasonable construction in light of the specification of the application or paten t in which it appears.”); Crish , 393 F.3d at 1256 (“[O]ur review of the Board's claim constr uction is limited to determining whether it was reasonable.”). Both parties agree that the initial i ssue in this appeal turns upon the Board’s construction of Diab’s claim 39. Yorkey ar gued to the Board that the claims at issue differ because “[c]laim 39 of Diab’s . . . applic ation 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 intens ity signal’, whereas claim[ ] 6 . . . of Yorkey’s . . . patent use[s] all three functions to obtai n 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 us ed in the final calculation of saturation by the use of matrix algebra. Causevic testified that, in c ontrast, 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 upo n the third intensity signal.’” Diab’s expert, Dr. Gail D. Baura (“Baur a”), 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 satura tion 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.

2008-1578 6(alterations in original). Baura furt her disagreed with Causevic that the Diab application’s claim does not solve the thr ee 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 calc ulations, 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 pa ir of limitations commencing with “wherein”, Causevic testified that in Yorkey’s limitation: [T]he coefficients of the third wavel ength function are determined by taking measurements in the absence of moti on noise and determining saturation from first and second intensity signal s....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 ultima te determination of saturation based on only two wa velengths”, 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 wh ich 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]h e 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 approxim ating a portion of the fi rst and second signals

2008-1578 7based on the third signal first and using the approximation to calculate the saturation by putting the functions into a matrix and solv ing 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 matr ix and solving them together. The Board found Baura’s testimony to be mo re credible than that of Causevic because it was more consist ent with the language of the claims. The Board was not persuaded by Yorkey’s argument that solving the three func tions to obtain a value for oxygen saturation required solving the thr ee 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 br oadest reasonable construction. Nor did the Board accept Causevic’s argum ent that Yorkey’s claims exclude the Diab application’s approximation step; rather , it accepted Baura’s contention that the approximation step is simply a st ep 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 satu ration.” (emphasis in original). This is improper, contends Yorkey, because the language of the limitat ion 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 subt racted. Thus, Diab’s claim 39 cannot be construed to require “solving the three functions to obtai n a value for saturation.”

2008-1578 8According to Yorkey, “such a construction w ould necessarily requir e that, regardless of which functions are solved for saturation, all th ree must represent a si gnal as a function of saturation and be solved as such.” Yorkey’s argument fails. The specificat ion of the Diab application provides, in Equations (93), (94), and (95), the three f unctions derived from each of the three signals recorded from the probe

. Each of these functions is time-dependent, as indicated by the term S λ n (t) for each function, where n equals o ne of the three si gnals, Red1, Red2, or IR. Factors in each function are ε HbO2, λ n c A , representing the concentration of oxygenated hemoglobin in the blood, and n λ n (t), a noise component. Diab teaches that each function is solved sequenti ally to obtain a value fo r oxygen saturation Thus,
contra Yorkey, all three functions represent a signal as a function of saturation, and the sequential process of the functi ons’ solution is necessarily required to obtain a final value for saturation. For these reasons, we find that the Boar d’s denial of Yorkey’s motion for judgment of no interference-in-fact is su pported by substantial evidence, and we consequently affirm th e Board’s decision. Yorkey next argues that even if the B oard correctly construed the language of Claim 39, there is no written description in the Diab applicati on to support it. The written description requirement set forth by 35 U.S.C. § 112, ¶ 1 states that: The specification shall contain a writt en 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 enab le any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same.

2008-1578 935 U.S.C. § 112, ¶ 1. Whether the written description requi rement 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 repres ents 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 isused merely to generate a noise reference signal that is used to subtract the motioninduced noise component from the other two remaining signals . The resulting functions representing those two signal s are subsequently solved to yield a value representing the oxygen saturation. Yorkey disputes Baura’s expert testim ony (with which the Board ultimately agreed) that the “solving the three functions” limitation is suppor ted because the Diab application allegedly discloses “using the th ird wavelength” to generate a reference signal and therefore the th ird signal is still used in the ul timate calculation of saturation Yorkey maintains that the third intensity signal is not represented as a function of

2008-1578 10saturation, 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 Di ab application first specifie s the emitter and detection of the third signal at issue: The third [light-emitting diode (“LED”)] 304 is used to measure a third signal S λ c (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 thir d 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 λ a , λ b , and λ c are: S λ a (t) = S λ red1 (t) = 

### ε HbO2 , λ a c A HbO2 x A (t) + 

### ε Hb, λ a c A Hb x A (t) + 

### ε HbO2 , λ a c V HbO2 x V (t) + 

### ε Hb, λ a c V Hb x V (t) + n λ a (t). 

### (93)
S λ b (t) = S λ red2 (t) = 

### ε HbO2 , λ b c A HbO2 x A (t) + 

### ε Hb, λ b c A Hb x A (t) + 

### ε HbO2 , λ b c V HbO2 x V (t) + 

### ε Hb, λ b c V Hb x V (t) + n λ b (t). 

### (94)
S λ c (t) = S λ IR (t) = 

### ε HbO2 , λ c c A HbO2 x A (t) + 

### ε Hb, λ c c A Hb x A (t) + 

### ε HbO2 , λ c c V HbO2 x V (t) + 

### ε Hb, λ c c V Hb x V (t) + n λ c (t). 

### (95) 2 In each equation, the term S λ (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 Di ab application represented by Equation (94) (the Red2 LED signal) is not merely composed of moti on-induced noise, but rather contains

2 Each equation is, of course, a function because the term S λ (red1) red 2) or (IR) (t) represents the result of an operation.

2008-1578 11components of both transmitte d light representing oxygen saturation (i.e., 

### ε HbO2 , λ b

c A HbO2 x A (t) + 

### ε Hb, λ b c A Hb x A (t) + 

### ε HbO2 , λ b c V HbO2 x V (t) + + 

### ε Hb , λ b c V Hb x V (t) + n λ b (t), where HbO2 represents the concentration of oxygen-bound hemoglobin, Hb represents the concentration of free hemoglobin, A represent s arterial blood, V represents venous blood and n represents motion-induc ed noise). This function is, in effect, identical to the other two functions representi ng the other two sign als detected with th e exception of the varying wavelengths. The Diab application teaches that the two red wavelengths are selected to satisfy a proportionality relationship which re moves the primary signal portions S λ red1 (t) and S λ red2 (t) yielding a secondary reference, n’(t) by choosing two wavelengths that cause the primary portions of t he measured signals for each to become linearly dependent. By so choosing, the venous portions like wise become linearly dependent, which allows removal of these signals, generating the sec ondary reference signal, n’(t). The signal so generated can be used in a correlation cancel ler, 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 pl urality of coefficients related to the wavelengths, the coefficients of sa id 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 S λ red1 (t) and S λ red2 (t) as well as to n λ n (t)), and the

2008-1578 122008-1578 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 specif ication approximates at leas t a portion of the first and second intensity signals based upon the third in tensity signal (performed by selecting a wavelength for the third emitt ed signal that satisfies a pr oportionality relationship which removes the primary signal portions S λ red1 (t) and S λ red2 (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 oxyg en saturation of the blood, based upon the approxim ation of the first and second signals so derived. The language in the limitation thus provides a written de scription 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 t he 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-f act and his motion for judgment that claim 39 of the Diab application fails to comply wit h the written descripti on of requirement of 35 U.S.C. § 112, ¶ 1. AFFIRMED