Case: 19-1879 Document: 59 Page: 1 Filed: 08/06/2020
`NOTE: This disposition is nonprecedential.
`United States Court of Appeals
`for the Federal Circuit
`Appeal from the United States Patent and Trademark
`Office, Patent Trial and Appeal Board in Nos. IPR2017-
`02012, IPR2018-00275.
`Decided: August 6, 2020
`JEFFREY AHDOOT, Blackbird Tech LLC, Boston, MA, for
`appellant. Also represented by WENDY VERLANDER;
`STAMATIOS STAMOULIS, Stamoulis & Weinblatt LLC, Wil-
`fices of David A. Gerasimow, P.C., Chicago, IL.
` CLEMENT ROBERTS, Orrick, Herrington & Sutcliffe
`LLP, San Francisco, CA, for appellee Fitbit, Inc. Also rep-
`resented by ELIZABETH MOULTON, Menlo Park, CA; ERIC


`Case: 19-1879 Document: 59 Page: 2 Filed: 08/06/2020
`SHUMSKY, Washington, DC.
` MATTHEW L. CUTLER, Harness, Dickey & Pierce, PLC,
`St. Louis, MO, for appellee Wahoo Fitness LLC. Also rep-
` ______________________
`Before PROST, Chief Judge, REYNA and TARANTO, Circuit
`TARANTO, Circuit Judge.
`Blackbird Tech LLC, d/b/a Blackbird Technologies,
`owns U.S. Patent No. 6,434,212, which describes and
`claims a device that counts an individual’s steps and, based
`on the length and rate of those steps, provides the individ-
`ual with information such as distance traveled and speed.
`Fitbit, Inc. and Wahoo Fitness LLC each sought an inter
`partes review of claims 2, 5, and 6 of the ’212 patent. The
`Patent Trial and Appeal Board of the Patent and Trade-
`mark Office instituted the requested reviews and consoli-
`dated the proceedings. The Board ultimately determined
`that Fitbit had proven claim 6 of the ’212 patent unpatent-
`able for obviousness but had not proven claims 2 and 5 un-
`patentable. See FitBit, Inc. v. Blackbird Tech, LLC, No.
`IPR2017-02012, 2019 WL 1118863 (P.T.A.B. Mar. 11,
`2019). Blackbird appeals the Board’s ruling on claim 6. We
`The ’212 patent describes purported improvements in
`a pedometer, i.e., a device “for determining the distance a
`person travels on foot.” ’212 patent, col. 1, lines 18–19. The
`basic components of the assertedly inventive pedometer
`are a step counter, a wearable receiver, and a data proces-
`sor programmed to use the step count, as well as the stride
`length and the rate of steps, to derive information such as


`Case: 19-1879 Document: 59 Page: 3 Filed: 08/06/2020
`distance traveled or speed. See id., col. 2, line 15–23. The
`patent “recognizes the interdependency of stride length
`and stride rate” (how many steps per unit of time), id., col.
`2, lines 24–25, and provides for adjusting the stride length
`with new data—based on, e.g., the wearer’s actual walk-
`ing—to improve accuracy in calculating the figures of in-
`terest, such as distance or speed, id., col. 2, at lines 25–26,
`For example, starting with an initially input “base
`stride length,” id., col. 3, lines 56–64, the device can use a
`wearer’s actual walking to “correct[]” the base stride length
`to “arrive at an accurate Actual Stride Length,” id., col. 4,
`lines 30–46. Once the walker’s “actual stride length is cal-
`culated for a given period of time, the value can be multi-
`plied by the number of strides in that period to obtain a
`total distance for that period.” Id., col. 6, lines 33–38. This
`total distance can then be used to calculate speed. See id.,
`col. 6, lines 43–45.
`Claim 6, the only claim at issue here, recites:
`6. A pedometer comprising:
`a step counter;
`a transmitter in communication with the step
`counter to generate a step count signal corre-
`sponding to each step and transmit the step
`count signal;
`a receiver mountable on a user body portion to re-
`ceive the step count signal transmitted from
`the transmitter; and
`a data processor programmed to calculate a dis-
`tance traveled by multiplying a number of
`steps counted by a stride length that varies ac-
`cording to a rate at which steps are taken, and
`further programmed to derive an actual stride


`Case: 19-1879 Document: 59 Page: 4 Filed: 08/06/2020
`length from a range of stride lengths calculated
`from a range of corresponding stride rates.
`Id., col. 8, lines 5–19.
`In August 2017, Fitbit petitioned for an inter partes re-
`view of claims 2, 5, and 6 of the ’212 patent. Fitbit argued
`that the claims are unpatentable on three grounds: first,
`claims 2 and 5 are anticipated by U.S. Patent No. 6,241,684
`(Amano); second, claims 2 and 5 are unpatentable for obvi-
`ousness over Amano; and third, claim 6 is unpatentable for
`obviousness over a combination of Amano and U.S. Patent
`No. 5,033,013 (Kato). In December 2017, Wahoo petitioned
`for an inter partes review of claims 2, 5, and 6, relying on
`the same grounds as Fitbit.
`The Board instituted a review based on Fitbit’s peti-
`tion, though not on the first ground. The Board then insti-
`tuted a review based on Wahoo’s petition and joined Wahoo
`to the Fitbit proceeding. After the Supreme Court’s deci-
`sion in SAS Institute Inc. v. Iancu, 138 S. Ct. 1348 (2018),
`the Board added the first ground to the proceedings.
`In its final written decision, the Board determined that
`Fitbit had not proven claims 2 and 5 unpatentable but that
`Fitbit had proven claim 6 unpatentable for obviousness
`over a combination of Kato and Amano. FitBit, 2019 WL
`1118863, at *11–14. Blackbird timely appealed; Fitbit and
`Wahoo did not appeal. We have jurisdiction under 28
`U.S.C. § 1295(a)(4)(A).
` On appeal, Blackbird limits its challenge to one point,
`contending that the Board erred in finding that Kato dis-
`closes claim 6’s limitation “a data processor programmed to
`calculate a distance traveled by multiplying a number of
`steps counted by a stride length.” Although we review the
`Board’s determination of obviousness de novo, we review


`Case: 19-1879 Document: 59 Page: 5 Filed: 08/06/2020
`its underlying factual findings for substantial evidence
`support, Personal Web Technologies, LLC v. Apple, Inc.,
`848 F.3d 987, 991 (Fed. Cir. 2017), and “findings as to the
`scope and content of the prior art” are factual findings, Ari-
`osa Diagnostics v. Verinata Health, Inc., 805 F.3d 1359,
`1364 (Fed. Cir. 2015). Accordingly, we review the Board’s
`finding as to what Kato taught a relevant skilled artisan
`for whether it is supported by substantial evidence, i.e.,
`“whether a reasonable fact finder could have arrived at the
`agency’s decision” on the record as a whole. Intelligent Bio-
`Systems, Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359,
`1366 (Fed. Cir. 2016); In re Gartside, 203 F.3d 1305, 1312
`(Fed. Cir. 2000).
` Kato discloses a processing means that uses a walker’s
`stride length, along with the walker’s “pitch,” to determine
`the walker’s speed. When the walker’s foot hits the ground,
`a detector notifies the processing means of the contact.
`Kato, col. 3, line 67, through col. 4, line 3. Over a “prede-
`termined unit of time,” the processing means counts the
`number of contacts received to obtain the walker’s “pitch,”
`i.e., the walker’s step rate (number of steps per selected
`time unit). Id., col. 4, lines 4–6; see id., col. 4, line 16 (“PI
`is the pitch in number of steps every 10 seconds”). Because
`of a “predetermined empirical relationship” between the
`walker’s pitch, height, and stride length, Kato explains, ob-
`taining the walker’s pitch also allows the processing means
`to calculate the walker’s stride length (which Kato just
`calls “stride”). See id., col. 4, lines 7–10. Then, “the stride
`is multiplied by the pitch [] to obtain a walking speed of the
`walker in said unit of time.” Id., col. 4, lines 50–51. Kato
`expresses this step in the form of a simple equation:
`SP = ST × PI
`Id., col. 4, line 27. In this equation, SP is “speed of walk-
`ing,” ST is “stride in meters,” and PI is “pitch in number of
`steps every 10 seconds” (i.e., steps/unit of time). Id., col. 4,
`lines 17–19, 25–27.


`Case: 19-1879 Document: 59 Page: 6 Filed: 08/06/2020
` Using the “same steps as in the method of measuring
`walking speed,” Kato discloses calculating the distance
`traveled by the walker over a given period of time by add-
`ing an extra step—“multiplying the walking speed by said
`unit of time.” Id., col. 4, lines 59–68. Although Kato does
`not present this calculation in equation form, the equation
`form of those words is simply D = SP × T, where D is dis-
`tance in meters and T is the period of time in seconds. Be-
`cause Kato has just explained that SP = ST × PI, it is
`evident from Kato that:
`D = ST × PI × T.
`Substantial evidence supports the Board’s finding that
`a relevant skilled artisan would read Kato as teaching a
`“data processor programmed to calculate a distance trav-
`eled by multiplying a number of steps counted by a stride
`length.” As the Board noted, Kato’s equation for calculat-
`ing distance can be expressed “in measurement terms: me-
`ters * (steps/time) * (time).” FitBit, 2019 WL 1118863, at
`*11. That is directly supported by the above equation, be-
`cause ST is the stride length in meters, PI is steps/time,
`and T is the period of time (for which the distance is being
`derived). Given that “[n]othing in Kato precludes the pe-
`riod of time and unit time from being the same,” the Board
`observed, the “period of time” in the numerator and the
`“unit time” in the denominator cancel out. Id. at *12. In
`other words, D = ST × steps. As a result, the Board ex-
`plained, Kato’s method for calculating distance travelled
`can be expressed as simply “determining the number of
`steps and multiplying them by a stride length.” Id.
` On appeal, Blackbird argues that the Board was obli-
`gated to explain why a relevant skilled artisan would have
`taken the steps of expressing pitch as “steps/time” and can-
`celling out the numerator-time with the denominator-time.
`According to Blackbird, the Board “worked backward, with
`knowledge of the claimed invention, to modify the Kato


`Case: 19-1879 Document: 59 Page: 7 Filed: 08/06/2020
`reference in such a way so as to arrive at the claimed in-
`vention.” Appellant’s Br. at 13.
`But the Board’s conclusion of unpatentability did not
`rely on a modification of Kato’s equation—it relied on a
`finding that a relevant skilled artisan would consider
`Kato’s equation to teach claim 6’s limitation. To determine
`the “meaning of a prior art reference,” the Board must in-
`corporate “the understanding of an artisan of ordinary
`skill.” Finisar Corp. v. DirecTV Grp., Inc., 523 F.3d 1323,
`1336 (Fed. Cir. 2008). Here, the Board determined that a
`relevant skilled artisan would be an engineer with either a
`master’s degree or multiple years of work experience. Fit-
`Bit, 2019 WL 1118863, at *5. The Board could readily find
`that such a person would understand Kato’s teaching of a
`very simple multiplicative relationship to teach the form of
`that relationship that involves the elementary process of
`unit cancellation between numerator and denominator.
`Accordingly, the Board had a sufficient basis to find that a
`relevant artisan would have considered Kato’s method for
`calculating distance traveled to be identical to claim 6’s
`For the foregoing reasons, the Board’s decision is af-
`Costs awarded to appellees.

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