`571-272-7822
`
`Paper 7
`Entered: April 16, 2021
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`UNITED STATES PATENT AND TRADEMARK OFFICE
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`
`APPLE INC.,
`Petitioner,
`v.
`MASIMO CORPORATION,
`Patent Owner.
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`IPR2020-01526
`Patent 6,771,994 B2
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`
`Before JOSIAH C. COCKS, ROBERT L. KINDER, and
`AMANDA F. WIEKER, Administrative Patent Judges.
`KINDER, Administrative Patent Judge.
`
`DECISION
`Granting Institution of Inter Partes Review
`35 U.S.C. § 314, 37 C.F.R. § 42.4
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`I.
`
`INTRODUCTION
`
`Background
`A.
`Apple Inc. (“Petitioner”) filed a Petition requesting an inter partes
`review of claim 15 of U.S. Patent No. 6,771,994 B2 (Ex. 1001, “the ’994
`patent”). Paper 2 (“Pet.”). Masimo Corporation (“Patent Owner”) waived
`filing a Preliminary Response. Paper 6 (“PO Waiver”).
`We have authority to determine whether to institute an inter partes
`review, under 35 U.S.C. § 314 and 37 C.F.R. § 42.4. An inter partes review
`may not be instituted unless it is determined that “the information presented
`in the petition filed under section 311 and any response filed under
`section 313 shows that there is a reasonable likelihood that the petitioner
`would prevail with respect to at least 1 of the claims challenged in the
`petition.” 35 U.S.C. § 314 (2018); see also 37 C.F.R § 42.4(a) (“The Board
`institutes the trial on behalf of the Director.”).
`For the reasons provided below and based on the record before us, we
`determine that Petitioner has demonstrated a reasonable likelihood that
`Petitioner would prevail in showing the unpatentability of claim 15.
`Accordingly, we institute an inter partes review on all grounds set forth in
`the Petition.
`
`Related Matters
`B.
`The parties identify the following matters related to the ’994 patent:
`Masimo Corporation v. Apple Inc., Civil Action No. 8:20-cv-00048
`(C.D. Cal.) (filed Jan. 9, 2020);
`Apple Inc. v. Masimo Corporation, IPR2020-01520 (PTAB
`Aug. 31, 2020) (challenging claims of U.S. Patent No. 10,258,265 B1);
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`Apple Inc. v. Masimo Corporation, IPR2020-01521 (PTAB
`Sept. 2, 2020) (challenging claims of U.S. Patent No. 10,292,628 B1);
`Apple Inc. v. Masimo Corporation, IPR2020-01523 (PTAB
`Sept. 9, 2020) (challenging claims of U.S. Patent No. 8,457,703 B2);
`Apple Inc. v. Masimo Corporation, IPR2020-01524 (PTAB
`Aug. 31, 2020) (challenging claims of U.S. Patent No. 10,433,776 B2);
`Apple Inc. v. Masimo Corporation, IPR2020-01536 (PTAB
`Aug. 31, 2020) (challenging claims of U.S. Patent No. 10,588,553 B2);
`Apple Inc. v. Masimo Corporation, IPR2020-01537 (PTAB
`Aug. 31, 2020) (challenging claims of U.S. Patent No. 10,588,553 B2);
`Apple Inc. v. Masimo Corporation, IPR2020-01538 (PTAB
`Sept. 2, 2020) (challenging claims of U.S. Patent No. 10,588,554 B2); and
`Apple Inc. v. Masimo Corporation, IPR2020-01539 (PTAB
`Sept. 2, 2020) (challenging claims of U.S. Patent No. 10,588,554 B2).
`Pet. 68; Paper 3, 2.
`
`The parties further identify certain pending patent applications, as
`well as other issued applications, that claim priority to, or share a priority
`claim with, the ’994 patent. Paper 3, 1.
`
`The ’994 Patent
`C.
`The ’994 patent is titled “Pulse Oximeter Probe-Off Detection
`System,” and issued on August 3, 2004, from U.S. Patent Application
`No. 10/374,303, filed February 24, 2003. Ex. 1001, codes (21), (22), (45),
`(54). The ’994 patent claims priority through a series of applications to
`Provisional Application No. 60/140,000, filed June 18, 1999. Id. at
`codes (60), (62).
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`The ’994 patent relates to a pulse oximeter probe that detects when a
`probe has become dislodged from a patient or that acts to prevent a potential
`probe-off condition. Ex. 1001, code (57). The ’994 patent relies on
`electrical contacts that contact the skin of a patient when the probe is
`properly attached and a number of louvers placed in front of a sensor’s
`photodetector to filter out oblique light rays that do not originate from a
`point in front of the detector. Id. According to one aspect of the invention,
`if the emitter and photodetector are not properly aligned, the photodetector
`will not produce a signal within the valid operating range of the pulse
`oximeter, which may trigger an alarm or warning. Id.
`As depicted in Figure 1 below, pulse oximeter 140 is attached through
`connector 142 to probe 110 and probe 110 comprises LEDs 112, 114, which
`are “preferably configured to produce different wavelengths of light.” Id. at
`3:21–55, Fig. 1.
`
`
`Figure 1 illustrates a schematic of a pulse oximeter system. Id. at 2:30–31.
`The wavelengths of light pass through the flesh of a patient to be detected by
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`photodetector 116. Id. at 3:34–37, Fig. 1. The ’994 patent describes certain
`embodiments where the photodetector is placed opposite the light emitters to
`detect transmitted light as it emerges from the user’s body tissue. See id.,
`1:41–43 (describing the configuration of known pulse oximetry probes as
`positioning the detector “opposite the LED”), 4:19–25 (“the emitters located
`within the probe are spaced opposite the detector assembly 235 . . . such that
`the light from the emitters passes . . . through the finger 250 and is incident
`upon the detector assembly 235”), Figs. 2A–B, 4, 5A–B.
`As illustrated in Figure 5B below, if probe 202 is properly attached
`emitter aperture 220 will be directly in front of detector assembly 235 and
`light rays will pass directly through louvers 502 along direct path 510. Id. at
`6:29–33.
`
`
`Figure 5B illustrates a properly attached probe wherein a number of
`louvers (502) are placed in front of the detector assembly. Ex. 1001, 2:60–
`62.
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`D. Claim 15
`Claim 15 is the only challenged claim and it is reproduced below.
`1. A sensor which generates at least first and second
`intensity signals from a light-sensitive detector which detects
`light of at least first and second wavelengths transmitted through
`body tissue carrying pulsing blood; the sensor comprising:
`[a] at least one light emission device;
`[b] a light sensitive detector; and
`[c] a plurality of louvers positioned over the light sensitive
`detector to accept light from the at least one light emission device
`originating from a general direction of the at least one light
`emission device and then transmitting through body tissue
`carrying pulsing blood, wherein the louvers accept the light when
`the sensor is properly applied to tissue of a patient.
`Ex. 1001, 8:21–35 (bracketed identifiers a–c added).
`
`Applied References
`E.
`Petitioner relies upon the following references:
`Diab et al., U.S. Patent No. 5,638,818, filed November 1, 1994,
`issued June 17, 1997 (Ex. 1006, “Diab”);
`Benjamin et al., U.S. Patent No. 4,015,595, filed
`September 15, 1975, issued April 5, 1977 (Ex. 1007, “Benjamin”);
`Melby et al., U.S. Patent No. 5,254,388, filed December 20,
`1991, issued October 19, 1993 (Ex. 1008, “Melby”);
`Fine, WO Pub. No. 1996/41566, filed June 6, 1995, published
`December 27, 1996 (Ex. 1009, “Fine”); and,
`Webster, Excerpts from Design of Pulse Oximeters, J.G.
`Webster; Institution of Physics Publishing, 1997 (Ex. 1010,
`“Webster”).
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`Pet. 3-4.
` Petitioner also submits, inter alia, the Declaration of Brian W.
`Anthony, Ph.D. (Ex. 1003).
`
`Asserted Grounds
`F.
`Petitioner asserts that claim 15 is unpatentable based upon the
`following grounds:
`
`Claim Challenged
`
`15
`15
`15
`15
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`35 U.S.C.
`§
`103
`103
`103
`103
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`Reference(s)/Basis
`Diab, Benjamin, Melby
`Webster, Melby
`Fine
`Fine, Benjamin, Melby
`
`II. DISCUSSION
`Claim Construction
`A.
`For petitions filed on or after November 13, 2018, a claim shall be
`construed using the same claim construction standard that would be used to
`construe the claim in a civil action under 35 U.S.C. § 282(b), including
`construing the claim in accordance with the ordinary and customary
`meaning of such claim as understood by one of ordinary skill in the art and
`the prosecution history pertaining to the patent. 37 C.F.R. § 42.100(b)
`(2019).
`Petitioner submits that the entirety of clause 1[c] requires
`construction. Pet. 8. As noted above, Patent Owner did not file a
`Preliminary Response. See generally PO Waiver.
`Clause 1[c] (set forth above), requires in part, “a plurality of louvers
`positioned over the light sensitive detector to accept light from the at least
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`one light emission device originating from a general direction of the at least
`one light emission device and then transmitting through body tissue.”
`Ex. 1001, 8:29–35 (emphases added). Petitioner contends that this limitation
`requires that the light sensitive detector must “be positioned opposite the at
`least one light emission device.” Pet. 8–9. Petitioner seemingly bases this
`interpretation on one embodiment in the Specification, “which only depict[s]
`and describe the placement of the body tissue carrying pulsing blood
`between the at least one light emission device and the light sensitive
`detector.” Pet. 9 (citing Ex. 1001, 1:41–43 (“The photodiode is positioned
`opposite the LED so as to detect the LED transmitted light as it emerges
`from the [body] tissue.”)).
`Although Petitioner describes one embodiment of the invention that
`may be encompassed by the claim scope, this one embodiment is narrower
`in scope than the claim language of clause 1[c]. For example, the claim
`requires the louvers positioned over the detector to accept light originating
`from a general direction of the at least one light emission device, while the
`light also passes through tissue. Petitioner contends that for this to occur the
`detector must be positioned opposite the light emission device, as depicted
`in Figure 5B. Pet. 9.
`Petitioner’s position is understandable because the claim also requires
`that the louvers accept the light when the sensor is properly applied to tissue
`of a patient, which as Petitioner notes encompasses the embodiment of
`Figure 5B. Petitioner does not explain, however, why it is even necessary to
`adopt its proposed claim construction. For purposes of our analysis, we
`accept that the embodiment Petitioner relies upon (positioned opposite) is
`within the claim scope of clause 1[c], but we are not prepared to limit the
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`claim to just this embodiment without further explanation and evidence.
`Indeed, clause 1[c] provides sufficient detail as to the positioning of
`elements such that further defining the limitation does not seem necessary
`based on the limited record before us.1
`The parties should also bring to the Board’s attention any arguments
`or decisions in related proceedings or the related district court litigation that
`impact the claim interpretation of any claim term in the ’994 patent. See
`Facebook, Inc. v. Sound View Innovations, LLC, IPR2017-00998, Paper 13
`(PTAB Sept. 5, 2017); see also 37 C.F.R. § 42.100(b) (“Any prior claim
`construction determination concerning a term of the claim in a civil action,
`or a proceeding before the International Trade Commission, that is timely
`made of record in the inter partes review proceeding will be considered.”).
`
`Principles of Law
`B.
`A claim is unpatentable under 35 U.S.C. § 103 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.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 406
`(2007). The question of obviousness is resolved on the basis of underlying
`
`
`1 We understand that Petitioner’s grounds based upon the “Fine” reference
`rely on an interpretation of the elements of 15[c] that encompasses
`“reflectance pulse oximeters, in which the emitters and detectors are
`positioned on the same side of the body tissue carrying pulsing blood.”
`Pet. 45. Petitioner should clarify in its reply which grounds are dependent
`on which claim interpretation, and further explain which interpretation it
`contends is proper, after considering Patent Owner’s response. Petitioner’s
`proposed interpretation would seemingly exclude the grounds based on
`“Fine.”
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`factual determinations, including (1) the scope and content of the prior art;
`(2) any differences between the claimed subject matter and the prior art;
`(3) the level of skill in the art; and (4) objective evidence of non-
`obviousness.2 Graham v. John Deere Co., 383 U.S. 1, 17–18 (1966). When
`evaluating a combination of teachings, we must also “determine whether
`there was an apparent reason to combine the known elements in the fashion
`claimed by the patent at issue.” KSR, 550 U.S. at 418 (citing In re Kahn,
`441 F.3d 977, 988 (Fed. Cir. 2006)). Whether a combination of prior art
`elements would have produced a predictable result weighs in the ultimate
`determination of obviousness. Id. at 416–417.
`In an inter partes review, the petitioner must show with particularity
`why each challenged claim is unpatentable. Harmonic Inc. v. Avid Tech.,
`Inc., 815 F.3d 1356, 1363 (Fed. Cir. 2016); 37 C.F.R. § 42.104(b). The
`burden of persuasion never shifts to Patent Owner. Dynamic Drinkware,
`LLC v. Nat’l Graphics, Inc., 800 F.3d 1375, 1378 (Fed. Cir. 2015).
`We analyze the challenges presented in the Petition in accordance
`with the above-stated principles.
`
`Level of Ordinary Skill in the Art
`C.
`Petitioner identifies the appropriate level of skill in the art as that
`possessed by a person having “a Bachelor of Science degree in an academic
`discipline emphasizing the design of electrical, computer, or software
`technologies, in combination with training or at least one to two years of
`related work experience with capture and processing of data or information,
`
`
`2 At this stage of the proceeding, neither party has introduced objective
`evidence of non-obviousness.
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`including but not limited to physiological monitoring technologies.” Pet. 7–
`8 (citing Ex. 1003 ¶¶ 1–15, 36–37). “Additional education in a relevant field
`or industry experience may compensate for one of the other aspects of the
`POSITA characteristics stated above.” Id.
`For purposes of this Decision, we generally adopt Petitioner’s
`assessment as set forth above, which appears consistent with the level of
`skill reflected in the Specification and prior art.
`
`D. Obviousness over Diab, Benjamin, and Melby
`Petitioner presents undisputed contentions that claim 15 of the ’994
`patent would have been obvious over the teachings of Diab, Benjamin, and
`Melby. Pet. 10–29.
`
`Overview of Diab (Ex. 1006)
`1.
`Diab is titled “Low Noise Optical Probe.” Ex. 1006, code (54). Diab
`describes an “optical probe for measurements” for use in “non-invasive
`energy absorption (or reflection)” detection methods such as pulse oximetry.
`Id. at 3:12–14, Fig. 24, 17:66–67. The device includes a “light source, such
`as an LED” and a “detector, such as a photodetector.” Id. at 3:19–21, 3:30–
`31. Diab’s light source includes, for example, two “LEDs 430a and 430b,”
`one which emits “red wavelengths” and one which emits “infrared
`wavelengths.” Id. at 18:8–22.
`Petitioner provides the following annotated figure highlighting Diab’s
`LEDs 430a and 430b as well as photodetector 426.
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`Petitioner’s partial view of Figure 24 of Diab shows a schematic employing
`a probe with Petitioner’s annotations of LEDs 430a and 430b (blue) and
`photodetector 426 (green). Pet. 11; Ex. 1006, 5:25–26. Finger probe 400 is
`employed to measure a red and infrared signal that are alternatively passed
`through finger 428. Ex. 1006, 18:1–4. Signals measured at photodetector
`426 are then processed to determine the amount of oxygen available to the
`body. Id. at 18:4–6. LED 430a emits red wavelengths and LED 430b emits
`infrared wavelengths and both are placed adjacent finger 428. Id. at 18:9–
`14. Finger probe 400 is placed underneath finger 428, aperture 420, and
`chamber 422, which is located directly adjacent finger pad 404. Id.
`Non-invasive methods, as described by Diab, are “often desirable” in
`order to “monitor a patient without unnecessary drawing of blood or tissue.”
`Ex. 1006, 5:49–59. For example, “in the medical field, instead of extracting
`material from a patient’s body for testing,” non-invasive techniques often
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`use “light or sound energy . . . incident on the patient’s body” that is
`transmitted or reflected. Id. at 1:13–22.
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`Overview of Benjamin (Ex. 1007)
`2.
`Benjamin is titled “Photoplethysmographs.” Ex. 1007, code (54).
`According to Benjamin, a “photoplethysmograph,” is a device that uses a
`“light source and a specifically selected photo-sensitive cell that responds to
`light absorbed by the arterial blood in the peripheral vascular bed over which
`the sensor is placed.” Ex. 1007, 1:5–15. Benjamin describes using a probe
`including “a light source, a photo-sensitive cell and a light control film
`positioned in front of the light source and photo-sensitive cell for collimating
`the light emitted from the light source and reflected back to the photo-
`sensitive cell.” Id. at code (57).
`In order to “improve the accuracy of the photoplethysmographic
`pickup of the blood flow pulse,” Benjamin employs a “light control film” to
`collimate light passing through and “thereby make the photosensitive cell 20
`more nearly dependent only upon the light beam directly reflected from the
`field being measured.” Id. at 2:53–57. Benjamin states that such light films
`were “known in the art and . . . commercially available.” Id. at 2:50–52. As
`illustrated below, light source 18 directs light through window 16 and photo-
`sensitive cell 20 responds to light reflected from the field. Id. at 2:26–38.
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`Figure 1 of Benjamin is a sectional view of a photoplethysmographic probe.
`Ex. 1007, 2:16–17. Benjamin describes mounting light control film 22
`within casing 12 to extend across window 16. Light emitted from light
`source 18 passes through light control film 22 to the field to be measured
`and light is reflected from this field back through light control film 22 to
`photo-sensitive cell 20. Id. at 42–50.
`
`Overview of Melby (Ex. 1008)
`3.
`Melby is titled “Light Control Film with Reduced Ghost Images.”
`Ex. 1008, code (54). Melby discloses a light control film, or a “louvered
`plastic film.” Id. at code (57). Melby describes a film that includes “louver
`elements,” and Melby acknowledges that it was known to cant louver
`elements with respect to a louvered plastic film, which produces a film that
`transmits light in a direction other than perpendicular to the surface of the
`film. Id. at 1:9–22, 3:46–62. Melby describes using louvers having an outer
`portion with a relatively low optical density and an inner portion having a
`relatively high optical density. Id. at 3:21–22.
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`Independent Claim 15
`4.
`Petitioner contends that claim 15 would have been obvious over Diab,
`Benjamin, and Melby. Pet. 10–29. Petitioner has established a reasonable
`likelihood of prevailing on this asserted ground.
`
`i. [15 pre] “A sensor which generates at least first and
`second intensity signals from a light-sensitive detector
`which detects light of at least first and second wavelengths
`transmitted through body tissue carrying pulsing blood;
`the sensor comprising:”
`On this record, the cited evidence supports Petitioner’s undisputed
`contention that Diab, Benjamin, and Melby satisfy the subject matter of the
`preamble.3 Pet. 13–15. According to Petitioner, Diab teaches a sensor
`having a detector that detects “attenuated light energy signal [that] emerges
`from” a section of a subject’s body, “such as a finger, an earlobe, a toe, an
`organ, or a portion of tissue.” Pet. 13; Ex. 1006, 3:12–43. Notably, Diab’s
`sensor includes “a probe for use in both invasive and non-invasive energy
`absorption (or reflection) measurements,” and the probe includes a “detector,
`such as a photodetector” and a “light source, such as an LED” that is affixed
`“opposite the photodetector.” Id. at 3:11–47. Diab’s LED “emits light
`energy which propagates through and is absorbed by the material along the
`optical path length” and “an attenuated light energy signal emerges from the
`material.” Id. Diab’s “photodetector produces an electrical signal indicative
`of the intensity of the signal transmitted by the material,” such as a subject’s
`“finger 428.” Id. Petitioner explains that “[t]he subject’s finger, for
`
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`3 Whether the preamble is limiting need not be resolved at this stage of the
`proceeding, because Petitioner shows sufficiently for purposes of institution
`that the recitation in the preamble is satisfied by the prior art.
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`example, contains body tissue carrying pulsing blood.” Pet. 14 (citing
`Ex. 1003 ¶¶ 45–48).
`As shown above in Figure 24, Diab’s device includes two
`“LEDs 430a and 430b” that “alternately emit[] energy which is absorbed by
`the finger 428 and received by the photodetector 426” such that the
`photodetector “produces an electrical signal which corresponds to the
`intensity of the light energy striking the photodetector 426 surface.”
`Ex. 1006, 18:43–47. Petitioner contends that “Diab’s probe is ‘coupled to an
`oximeter. . . known in the art which utilizes light attenuation measurements,’
`such as a ‘pulse oximeter’ that measures signals from ‘two measured
`signals at different wavelengths, one of which is typically red and the other
`of which is typically infrared, [that] are alternately passed through the finger
`428.’” Pet. 15 (quoting Ex. 1006, 17:62–18:8). These signals are used to
`determine the amount of oxygen available to the body and are generated by
`“[t]wo LEDs 430a and 430b, one LED 430a emitting red wavelengths and
`another LED 430b emitting infrared wavelengths” that are placed adjacent to
`the subject’s finger. Ex. 1006, 17:62–18:8; Pet. 15.
`
`ii. “[a] at least one light emission device;”
`On this record, the cited evidence supports Petitioner’s undisputed
`contention that Diab discloses this limitation. Pet. 16–17. Specifically, Diab
`discloses two light emitting diodes (LEDs) that emit at two different
`wavelengths, as discussed in detail above. See Ex. 1006, Fig. 24
`(LEDs 430a, 430b), 3:11–47, 17:62–18:22.
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`iii. “[b] a light sensitive detector; and;”
`On this record, the cited evidence supports Petitioner’s undisputed
`contentions regarding this limitation. Pet. 17–18. Specifically, Petitioner
`contends that Diab describes a sensor that measures first and second
`intensity signals using a photodetector to detect light from at least two LEDs
`emitting at two different wavelengths. Pet. 17–18 (citing Ex. 1006, 3:11–47,
`17:62–18:22, Fig. 24; Ex. 1003 ¶¶ 45–52). “Diab’s photodetector produces
`signals that can be ‘processed to determine the amount of oxygen available
`to the body’ as part of a pulse oximeter.” Id. at 18 (quoting Ex. 1006, 18:4–
`6) (emphasis omitted).
`
`iv. “[c] a plurality of louvers positioned over the light
`sensitive detector to accept light from the at least one light
`emission device originating from a general direction of the
`at least one light emission device and then transmitting
`through body tissue carrying pulsing blood, wherein the
`louvers accept the light when the sensor is properly
`applied to tissue of a patient.”
`On this record, the cited evidence supports Petitioner’s undisputed
`contentions regarding these limitations. Pet. 19–29. Petitioner relies on the
`combined teachings of Diab, Benjamin, and Melby for teaching these
`limitations. Id.
`Diab teaches using a scattering medium positioned over the
`photodetector to provide an “improved optical signal-to-noise ratio” by
`minimizing the effects of local artifacts resulting from scattering as a result
`of motion. Ex. 1006, 3:63–4:5. Further, the scattering medium may be
`located between the material being tested and the photodetector, which
`results in an improved optical signal-to-noise ratio. Id. at 4:6–12; Pet. 19.
`Petitioner relies further on Diab’s disclosure that the film has the effect of
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`collimating the light passing through to make the photosensitive cell more
`nearly dependent only upon the light beam directly reflected from the field
`being measured. Id. at 2:50–57.
`Petitioner, relying on the testimony of Dr. Anthony, contends that a
`person of ordinary skill in the art “would have been motivated by the
`disclosure of Benjamin to modify Diab’s sensor to include a light control
`film in place of Diab’s scattering medium.” Pet. 21 (citing Ex. 1003 ¶ 62).
`Benjamin recognizes that “variations in the amount of scattered light
`reaching the photocell cause variations in the operating point of the
`photocell,” which “adversely affects the accuracy of the measurement.”
`Ex. 1007, 1:35–40; Ex. 1003 ¶¶ 57–59. Petitioner relies on Benjamin’s
`improvement of adding a light control film to stabilize the amount of
`scattered light that reaches the detector. Pet. 20 (quoting Ex. 1007, 1:56–66
`(“[T]he amount of scattered light reaching the photocell can be made closer
`to constant by placing in front of the photocell and light source a small piece
`of light control film. This film has the effect of collimating the light thereby
`to make the sensor more nearly dependent only upon the light beam directly
`reflected from the pulsating blood field.”)).
`On the current record, Petitioner argues persuasively that a person of
`ordinary skill in the art would have been motivated to combine Diab and
`Benjamin to provide an optical physiological sensor that reduces variations
`in the amount of light detected by the photodetectors of the sensor in order
`to collimate the light emitted from the light source and reflected back to the
`photo-sensitive cell. Pet. 22 (citing Ex. 1003 ¶¶ 57–62; Ex. 1007,
`code (57)). The references describe these advantages as leading to a more
`consistent and accurate measurement of blood oxygen saturation. Id.
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`Petitioner next relies on Melby as teaching the use of a louvered
`plastic film in the Diab/Benjamin combination. Pet. 25. Melby describes a
`“louvered plastic film [that] has louvers including central regions with a
`relatively high coefficient[] of extinction and outer regions with relatively
`low coefficients of extinction.” Ex. 1008, code (57). Petitioner notes that
`Melby is a patent assigned to Minnesota Mining and Manufacturing
`Company (3M) that describes a commercially available louvered light film
`made of “cellulose acetate butyrate (CAB).” Id. at 2:19–23, code (57);
`Pet. 13. Petitioner contends that a person of ordinary skill in the art would
`have considered the Melby louvered plastic film well known and the ’994
`patent itself notes that its “louvers” can be “created from commercially
`available ‘3M Light Control Film,’” such as that described in Melby.
`Ex. 1001, 6:39–41; Ex. 1003 ¶¶ 44, 69.
`Dr. Anthony testifies that “Melby describes a light control film that
`can be used with the combined Diab/Benjamin system” and “[a] POSITA
`would have been motivated to make this modification to further increase the
`directionality of the light signal received in the combined device, thereby
`leading to a device that is less susceptible to the influence of ambient light
`and thus provides more accurate readings.” Ex. 1003 ¶ 69. Petitioner relies
`on Melby’s teaching that “the effective optical density of a medium is
`directly proportional to the distance that the light must travel through that
`medium and the fact that reflection at an interface between two materials
`with different indices of refraction increases with increasing angle of
`incidence.” Pet. 27 (quoting Ex. 1008, 4:11–17) (citing Ex. 1003 ¶¶ 69–72).
`Petitioner contends that based on these disclosures, a person of ordinary skill
`in the art “would have recognized that Melby’s film could be used in the
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`Diab/Benjamin device to control light such that only light originating from
`the direction of the light emitters reaches the detector. Pet. 27–28. Further,
`Dr. Anthony testifies that incorporating Melby’s details regarding the
`implementation of Benjamin’s light control film would have been obvious to
`a person of ordinary skill in the art because doing so entails the use of
`known solutions to improve similar systems and methods in the same way.
`Ex. 1003 ¶ 73. Petitioner sufficiently shows on this record that it would
`have been obvious to a person of ordinary skill in the art to combine the
`specified teachings of Melby, Bejamin, and Diab for the reasons set forth
`above.
`
`v. Summary
`Petitioner sufficiently shows on this record, based on the
`uncontroverted testimony of Dr. Anthony, that a person of ordinary skill in
`the art would have found the sensor resulting from the combination of Diab,
`Benjamin, and Melby to render obvious the requirements of limitation 15[c],
`as well as claim 15 as a whole. See Ex. 1003 ¶¶ 57–74. For the foregoing
`reasons, we are persuaded that Petitioner’s cited evidence and reasoning
`demonstrates a reasonable likelihood that Petitioner would prevail in its
`contentions regarding claim 15.
`
`E. Obviousness over Webster and Melby
`Petitioner presents undisputed contentions that claim 15 of the ’994
`patent would have been obvious over the teachings of Webster and Melby.
`Pet. 29–44.
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`Overview of Webster (Ex. 1010)
`1.
`Webster is a book that provides an overview of the history and design
`of pulse oximeters, stating that “[p]ulse oximetry was introduced in 1983 as
`a noninvasive method for monitoring the arterial oxygen saturation of a
`patient’s blood.” Ex. 1010, xv4. The book details “both the hardware and
`software required to fabricate a pulse oximeter as well as the equations,
`methods, and software required for effective functioning” in addition to
`“testing methods.” Id. Petitioner relies on Webster for its comprehensive
`summary of the state of the art as of 1997, and its description of the purpose
`of components of a pulse oximeter as well as the design process and
`selection criteria for particular components. Pet. 30; Ex. 1003 ¶ 75. See
`generally Ex. 1010, Chs. 2, 5–7.
`
`Independent Claim 15
`2.
`Petitioner contends that claim 15 would have been obvious over
`Webster and Melby. Pet. 29–44. Petitioner has established a reasonable
`likelihood of prevailing on this asserted ground.
`
`
`4 Although Petitioner has added page numbering to the bottom of Exhibit
`1010, Petitioner cites to the original page numbers at the top of the book.
`We adopt Petitioner’s citations for clarity. But even still, Petitioner quotes
`from page xv, but cites to page xvi. For future reference, Petitioner should
`have cited to its added page numbering for such a reference. See 37 C.F.R.
`§ 42.63(d)(2)(i).
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`i. [15 pre] “A sensor which generates at least first and
`second intensity signals from a light-sensitive detector
`which detects light of at least first and second wavelengths
`transmitted through body tissue carrying pulsing blood;
`the sensor comprising:”
`On this record, the cited evidence supports Petitioner’s undisputed
`contention that Webster and Melby satisfy the subject matter of the
`preamble. Pet. 29–32. According to Petitioner, Webster describes devices
`known as “pulse oximeters,” which provide “an empirical measure of
`arterial saturation.” Pet. 30 (quoting Ex. 1010, 13). Webster describes the
`operation of the devices as shining “light of two wavelengths through a
`tissue bed such as the finger or earlobe and measures the transmitted light
`signal.” Id. (q