Universal Electronics, Inc. v. Roku, Inc. ( 2023 )


Menu:
  • Case: 21-1992   Document: 43     Page: 1   Filed: 08/18/2023
    NOTE: This disposition is nonprecedential.
    United States Court of Appeals
    for the Federal Circuit
    ______________________
    UNIVERSAL ELECTRONICS, INC.,
    Appellant
    v.
    ROKU, INC.,
    Appellee
    ______________________
    2021-1992, 2021-1993, 2021-1994
    ______________________
    Appeals from the United States Patent and Trademark
    Office, Patent Trial and Appeal Board in Nos. IPR2019-
    01612, IPR2019-01613, IPR2019-01614.
    ______________________
    Decided: August 18, 2023
    ______________________
    MICHAEL ANTHONY NICODEMA, Greenberg Traurig
    LLP, West Palm Beach, FL, argued for appellant. Also rep-
    resented by BENJAMIN GILFORD, JAMES J. LUKAS, JR., Chi-
    cago, IL.
    JON WRIGHT, Sterne Kessler Goldstein & Fox, PLLC,
    Washington, DC, argued for appellee. Also represented by
    RICHARD CRUDO, LESTIN KENTON; JONATHAN DANIEL
    BAKER, Dickinson Wright PLLC, Mountain View, CA;
    MICHAEL DAVID SAUNDERS, Austin, TX.
    Case: 21-1992    Document: 43      Page: 2    Filed: 08/18/2023
    2                  UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.
    ______________________
    Before NEWMAN, REYNA, and STOLL, Circuit Judges.
    NEWMAN, Circuit Judge.
    This is a consolidated appeal of three Inter Partes Re-
    view (“IPR”) petitions filed by Roku, Inc., for three patents
    derived from the same parent application and owned by
    Universal Electronics, Inc. (“UEI”). The Patent Trial and
    Appeal Board (“Board”) held that claims 1–4, 6, 8, 9, and
    22–25 of 
    U.S. Patent No. 7,589,642
     (“the ’642 patent”);
    claims 2–5, 7–13, and 15 of 
    U.S. Patent No. 8,004,389
     (“the
    ’389 patent”); and claims 1–5 of 
    U.S. Patent No. 9,911,325
    (“the ’325 patent”) are unpatentable on the ground of obvi-
    ousness. 1 The Board upheld challenged claim 14 of the ’389
    and claim 7 of the ’325 patent; Roku does not cross-appeal
    those rulings.
    For the reasons we discuss, we affirm the Board’s deci-
    sions in all three IPRs.
    BACKGROUND
    The Patented Inventions
    The three UEI patents are entitled “Relaying Key Code
    Signals Through a Remote Control Device,” and state that
    they relate “generally to remote control devices and, more
    specifically, to relaying key code signals through a remote
    control device to operate an electronic consumer device . . .
    1   Roku, Inc. v. Universal Elecs., Inc., No. IPR2019-
    01612, 
    2021 WL 1192127
     (P.T.A.B. Mar. 29, 2021); No.
    IPR2019-01613, 
    2021 WL 1192128
     (P.T.A.B. Mar. 29,
    2021); No. IPR2019-01614, 
    2021 WL 1395255
     (P.T.A.B.
    Apr. 13, 2021). The Board issued analogous opinions for all
    three reviews. Citations to “Board Op.” are to IPR2019-
    01612 unless otherwise noted.
    Case: 21-1992     Document: 43      Page: 3    Filed: 08/18/2023
    UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.                    3
    such as televisions, stereo radios, digital video disk players,
    video cassette recorders, set-top cable television boxes and
    set-top satellite boxes.” ’642 patent, col. 1, ll. 6–16. 2
    The patents discuss problems accompanying the provi-
    sion and use of electronic remote control technology:
    A remote control device typically controls a selected
    electronic consumer device by transmitting infra-
    red key code signals to the selected electronic con-
    sumer device. The infrared signals contain key
    codes of a codeset associated with the selected elec-
    tronic consumer device. Each key code corresponds
    to a function of the selected electronic device, such
    as power on, power off, volume up, volume down,
    play, stop, select, channel up, channel down, etc. In
    order to avoid the situation where a remote control
    device unintentionally operates an electronic con-
    sumer device that is associated with a different re-
    mote control device, manufacturers sometimes use
    distinct codesets for the communication between
    various electronic consumer devices and their asso-
    ciated remote control devices.
    
    Id.,
     col. 1, ll. 21–34. The patents’ written descriptions elab-
    orate on these problems and describe a method to relay a
    key code through a “remote control device to control a se-
    lected one of multiple different electronic consumer devices
    without requiring the codeset associated with the selected
    electronic consumer device to be stored on the remote con-
    trol device.” 
    Id.,
     col. 1, ll. 51–55.
    The representative claim for each patent is as follows:
    2   The ’325 patent is a continuation of the ’389 patent,
    which is a continuation of the ’642 patent. The specifica-
    tions are the same. Unless otherwise noted the citations
    are to the ’642 patent.
    Case: 21-1992   Document: 43     Page: 4    Filed: 08/18/2023
    4                UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.
    [’642 patent] Claim 1. A method comprising:
    (a) receiving a keystroke indicator signal from
    a remote control device, wherein the key-
    stroke indicator signal indicates a key on
    said remote control device that a user has
    selected;
    (b) generating a key code within a key code gen-
    erator device using the keystroke indictor
    signal;
    (c) modulating said key code onto a carrier sig-
    nal, thereby generating a key code signal;
    and
    (d) transmitting said key code signal from said
    key code generator device to said remote
    control device.
    [’389 patent] Claim 2. A method comprising:
    (a) receiving a keystroke indicator signal from
    a remote control device, wherein the key-
    stroke indicator signal indicates a key on
    said remote control device that a user has
    selected;
    (b) generating a key code within a key code gen-
    erator device using the keystroke indicator
    signal, wherein said key code is part of a
    codeset that controls an electronic con-
    sumer device;
    (c) modulating said key code onto a carrier sig-
    nal, thereby generating a key code signal;
    (d) transmitting said key code signal from said
    key code generator device; and
    (e) identifying said codeset using input from a
    user of said remote control device, wherein
    said codeset is identified when said user
    Case: 21-1992    Document: 43     Page: 5    Filed: 08/18/2023
    UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.                   5
    stops pressing a key on said remote control
    device.
    [’325 patent] Claim 1. A first device for transmit-
    ting a command to control a functional operation
    of a second device, the first device comprising:
    a receiver;
    a transmitter;
    a processing device coupled to the receiver and
    the transmitter; and
    a memory storing instructions executable by
    the processing device, the instructions
    causing the processing device to:
    generate a key code using a keystroke indicator
    received from a third device in communica-
    tion with first device via use of the receiver,
    the keystroke indicator having data that
    indicates an input element of the third de-
    vice that has been activated;
    format the key code for transmission to the sec-
    ond device; and
    transmit the formatted key code to the second
    device in a key code signal via use of the
    transmitter;
    wherein the generated key code comprises a
    one of a plurality of key code data stored in
    a codeset, wherein the one of the plurality
    of key code data is selected from the codeset
    as a function of the keystroke indicator re-
    ceived from the third device, wherein each
    of the plurality of key code data stored in
    the codeset comprises a series of digital
    ones and/or digital zeros, and wherein the
    codeset further comprises time information
    Case: 21-1992    Document: 43     Page: 6    Filed: 08/18/2023
    6                 UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.
    that describes how a digital one and/or a
    digital zero within the selected one of the
    plurality of key code data is to be repre-
    sented in the key code signal to be trans-
    mitted to the second device.
    UEI appeals as to all the invalidated claims, arguing
    that the Board erred in holding that a skilled artisan would
    have been motivated to combine known wireless transmis-
    sion technology with known modulation techniques.
    The Cited References
    Roku filed separate petitions for IPR of the three pa-
    tents, citing Mishra, Rye, and Caris as primary references
    for relevant wireless transmission technology, combined
    with Dubil and Skerlos as references regarding relevant
    modulation techniques. UEI argues that the Board misun-
    derstood and misconstrued the references, that the Board
    erred in finding a motivation to combine the references,
    and that the combination of references does not teach the
    inventions claimed in the UEI patents.
    A
    Wireless transmission of key codes
    The Mishra, Rye, and Caris references relate to the
    wireless transmission of key codes:
    Mishra, U.S. Patent Pub. No. 2001/0005197
    The Mishra reference is titled, “Remotely Controlling
    Electronic Devices,” and describes “a way to program a re-
    mote control unit to handle a variety of electronic devices
    in a fashion which is easy and quick for the user.” 
    Id. at ¶ 5
    . The Mishra Abstract summarizes:
    A control system enables telephone calls to be an-
    swered remotely using a remote control unit also
    adapted to remotely control an electronic device
    such as VCR. A processor based station may
    Case: 21-1992     Document: 43     Page: 7    Filed: 08/18/2023
    UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.                   7
    communicate with a remote control unit using both
    infrared and radio frequency protocols to enable re-
    mote telephone communications and remote con-
    trol of electronic devices.
    Rye, U.S. Patent Pub. No. US2004/0080428
    The Rye reference is titled, “RF Audiovisual Compo-
    nent Remote Control System,” and states that the object is
    “to provide a remote control system for use in controlling
    the operation of a multi-brand audiovisual component sys-
    tem that is cost effective and reliable.” 
    Id. at ¶ 12
    . Its Ab-
    stract summarizes:
    A handheld remote control unit transmits binary
    coded rf address and control signals to an address-
    able transceiver where those signals are detected,
    decoded and processed to derive binary coded con-
    trol signals that are coded in accordance with the
    brands or manufacturers of the audiovisual compo-
    nents that are to be controlled along with the func-
    tion that is to be thus controlled for the addressed
    components.
    Caris, 
    U.S. Patent No. 7,562,128 B1
    The Caris reference is titled, “STB Connects Remote to
    Web Site for Customized Code Downloads,” and “addresses
    perceived disadvantages in conventional programming of a
    remote control to be used with consumer electronics equip-
    ment.” Board Op. at *13. Caris discusses the need for sim-
    plifying the process of configuring a remote for use with
    different pieces of equipment. ’128 patent, col. 3, ll. 37–42.
    The Abstract summarizes:
    A set top box (STB) is marketed together with a
    programmable remote. The remote has a dedicated
    button to connect the STB to a specific server on
    the Internet. The consumer can notify the server
    of his/her other CE equipment, which he/she de-
    sires to be controllable through the same remote as
    Case: 21-1992    Document: 43     Page: 8    Filed: 08/18/2023
    8                 UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.
    the one that came with the STB. The server down-
    loads to the STB data representative of the rele-
    vant control codes. The STB is provided with
    means to program the remote with these codes. In
    return the server has obtained detailed and accu-
    rate information about this consumer’s equipment.
    A reliable customer base can thus be built for
    streamlining Help Desk operations.
    B
    Modulation techniques
    Dubil and Skerlos describe the transmission of control
    codes using known modulation techniques.
    Dubil, 
    U.S. Patent No. 8,132,105 B1
    The Dubil reference is titled, “Control Codes for Pro-
    grammable Remote Supplied in XML Format” and “relates
    to remote control devices and to a service for enabling the
    programming of remote controls to be used with consumer
    electronics (“CE”) equipment.” 
    Id.,
     col. 1, ll. 6–8. The Ab-
    stract describes the subject matter:
    An Internet service makes available control codes
    for use on a programmable universal remote. The
    remote controls CE equipment through IR or RF
    commands. A server supplies the control codes as
    XML data that gets processed at the receiver’s set
    top box or PC, or the remote itself, for being
    properly installed on the remote.
    The Board found that Dubil teaches “different modula-
    tion schemes that may be used in transmitting control
    codes having different bit patterns, including frequency-
    shift keying (“FSK”), binary phase-shift keying (“BPSK”),
    and pulse-width modulation (“PWM”).” Board Op. at *13.
    Dubil states that “[t]he invention covers both the usage of
    XML for IR or RF codes and for the GUI. The codes can be
    described using a number of parameters defined by XML
    Case: 21-1992     Document: 43     Page: 9    Filed: 08/18/2023
    UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.                    9
    tags. Examples have been mentioned above: carrier fre-
    quency, duty cycle, protocol type (FSK, biphase, PWM,
    etc.), repetition time, on/off[.]” Dubil, col. 4, ll. 33–37.
    Skerlos, 
    U.S. Patent No. 4,426,662
    The Skerlos reference is titled, “IR Remote Control De-
    tector/Decoder,” and “relates to remote control receivers
    and more specifically is directed to an infrared (IR) remote
    control detector/decoder providing improved noise immun-
    ity particularly adapted for use with a television receiver.”
    
    Id.,
     col. 1, ll. 5–9. The Abstract describes the subject mat-
    ter:
    A pulse code modulated (PCM) infrared (IR) remote
    control detector/decoder with improved noise im-
    munity particularly adapted for use with a televi-
    sion receiver is disclosed. The IR pulses are
    modulated by means of a high frequency dock sig-
    nal in translating the transmitted signal to a
    higher frequency, more noise immune portion of
    the IR spectrum. After receipt of the transmitted
    signal by a signal detector, the high frequency mod-
    ulation is removed from the pulses which are then
    decoded. Under the control of a microcomputer, the
    decoder looks for the start data bit and, if received,
    the subsequent control instructions. When the
    data transmission has been decoded, the microcom-
    puter activates the appropriate control outputs to
    the television receiver’s tuner system to achieve
    the desired control function.
    Skerlos explains that “[t]he present invention is utilized
    with a remote control system in which pulse code modu-
    lated (PCM) output signals are generated in response to
    user operated controls.” 
    Id.,
     col. 2, l. 67–col. 3, l. 2.
    DISCUSSION
    Obviousness is a question of law, based on underlying
    factual findings. In re NTP, Inc., 
    654 F.3d 1279
    , 1297 (Fed.
    Case: 21-1992    Document: 43     Page: 10    Filed: 08/18/2023
    10                 UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.
    Cir. 2011). On appeal from the Board, we review factual
    findings for support by substantial evidence and review le-
    gal conclusions de novo. Gen. Elec. Co. v. Raytheon Techs.
    Corp., 
    983 F.3d 1334
    , 1345 (Fed. Cir. 2020). Substantial
    evidence is “such relevant evidence as a reasonable mind
    might accept as adequate to support a conclusion.” Consol.
    Edison Co. v. NLRB, 
    305 U.S. 197
    , 229 (1938).
    Patent claim construction is a question of law that the
    court reviews de novo. Trs. Of Columbia Univ. v. Symantec
    Corp., 
    811 F.3d 1359
    , 1362 (Fed. Cir. 2016) (citing Teva
    Pharm. USA, Inc. v. Sandoz, Inc., 
    574 U.S. 318
     (2015))
    (“The construction of claim terms based on the claim lan-
    guage, the specification, and the prosecution history are le-
    gal determinations.”). When claim construction involves
    underlying factual findings, these findings are reviewed for
    support by substantial evidence. Knowles Elecs. LLC v.
    Cirrus Logic, Inc., 
    883 F.3d 1358
    , 1361–62, 1364 (Fed. Cir.
    2018).
    Claim Construction
    The Board invalidated various claims based on its con-
    struction of certain claim terms. UEI argues that the
    Board erred in construing and applying four terms: (A) the
    “generating” term relating to the key code of the ’642 pa-
    tent and the ’389 patent (“generating a key code within a
    key code generator device using the keystroke indicator
    signal”); (B) the “means” term in the ’389 patent (“means
    for receiving a key code from said RF receiver and for send-
    ing said key code to said IR transmitter such that said key
    code is modulated onto an IR carrier signal”); (C) the “pro-
    cessing device” term in the ’325 patent (“causing the pro-
    cessing device to: generate a key code . . . format the key
    code . . . and transmit the formatted key code”); and (D) the
    “timing information” term in the ’642 and ’325 patents
    (“codeset further comprises time information”).
    Case: 21-1992    Document: 43     Page: 11    Filed: 08/18/2023
    UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.                 11
    A
    The term “generating a key code”
    The Board held claims 1–4, 6, 8, 9, and 22–25 of the
    ’642 patent and claims 2–3 of the ’389 patent obvious over
    Mishra or Rye in combination with Dubil. UEI states that
    the Board erroneously construed “generating a key code
    within a key code generator device using the keystroke in-
    dicator signal” and that the Board’s construction is incon-
    sistent with the plain language of the claims and with the
    undisputed construction of the “key code generator device.”
    UEI Br. 2–3.
    UEI argues that the specifications and prosecution his-
    tories of the ’642 and ’389 patents state the correct con-
    struction and that “[t]he Board’s finding that Mishra and
    Rye disclose ‘generating a key code within a key code gen-
    erator device using the keystroke indicator signal’ is based
    on a construction of that limitation that includes ‘receiving
    an appliance control code and merely translating or con-
    verting the code into another format, such as an infrared
    signal.’” Id. at 44.
    UEI argues that under the correct construction “[n]ei-
    ther Mishra nor Rye discloses ’generating a key code within
    a key code generator device using the keystroke indicator
    signal.’” Id. at 50. UEI states that the Board found that
    “Mishra and Rye disclose merely ‘translating’ or ‘convert-
    ing’ a received key code into another format.” Id. UEI em-
    phasizes that “the correct construction of the limitation
    ‘generating a key code within a key code generator device
    using the keystroke indicator signal’ excludes ‘translating’
    or ‘converting’ a received key code into another format.” Id.
    Roku responds that the “generating” limitation as con-
    strued by the Board does not exclude translating or con-
    verting a key code into another format, and that “[t]he
    Board properly construed this limitation consistent with its
    plain and ordinary meaning to encompass scenarios where
    Case: 21-1992     Document: 43     Page: 12    Filed: 08/18/2023
    12                  UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.
    the set-top box (1) translates a keystroke indicator signal
    received from a remote control into a format appropriate
    for controlling a consumer device, as disclosed in Mishra;
    and (2) uses the received keystroke indicator signal to ob-
    tain the corresponding key code from a look-up table and
    converts the signal to the appropriate code, as disclosed in
    Rye and Caris.” Roku Br. 38–39. We discern no error in
    the Board’s statement:
    We are not persuaded that there is sufficient basis
    for construing the “generating” limitation so
    broadly as to capture the identification of a key
    code from a codeset while simultaneously excluding
    translation of a received code. By forgoing a
    straightforward recitation of “identifying” in the
    claims in favor of a broader recitation of “generat-
    ing,” the patentee clearly meant for the term not to
    be limited to mere identification of a key code but
    also to include other forms of generation of the key
    code.
    Board Op. at *11.
    Substantial evidence supports the Board’s finding that
    each of Mishra, Rye, and Caris discloses the “generating”
    limitation under the Board’s construction. Mishra gener-
    ates a key code signal by translating a command signal re-
    ceived from the remote control into a format suitable for
    controlling a device. The Board explained for claim 1 of the
    ’642 patent:
    Independent claim 1 recites “generating a key code
    within a key code generator device using the key-
    stroke indicator signal.” Petitioner contends that
    this limitation is disclosed by Mishra’s determina-
    tion of a corresponding control code through trans-
    lation of the command signal received from the
    RCU into a format appropriate for controlling an
    appliance . . . . In accordance with our adopted con-
    struction of the limitation, we agree that such
    Case: 21-1992    Document: 43     Page: 13    Filed: 08/18/2023
    UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.                   13
    translation qualifies as “generating a key code,”
    and that Mishra therefore meets the limitation.
    Board Op. at *15 (internal citations omitted).
    Rye describes converting an input control signal to be
    compatible with the operating binary code for the selected
    audiovisual component. The Board applied Rye to claim 2
    of the ’642 patent:
    Like independent claim l, independent claim 2 re-
    cites “generating a key code within a key code gen-
    erator device using the keystroke indicator signal.”
    Petitioner contends that this limitation is disclosed
    by Rye’s procedure of “convert[ing] the input con-
    trol signal so that it is compatible with the operat-
    ing binary code for the selected audiovisual
    component whose IR remote control code is ob-
    tained from the look-up table 46.”
    Board Op. at *21 (internal citations omitted).
    UEI argued to the Board that “Rye’s converting of a re-
    ceived control code was expressly disclaimed from ‘gener-
    ating a key code’ during prosecution.” Id. (quoting UEI
    Board Br. 40) The Board stated that “we disagree that
    there was an effective prosecution history disclaimer that
    limits the scope of the ‘generating’ limitation as Patent
    Owner proposes.” Id. Roku states that “UEI makes a sim-
    ilar argument on appeal. While UEI tries to disguise its
    true argument by not using the word ‘disclaimer’ in its
    brief, its invitation for the Court to depart from the ordi-
    nary meaning of ‘generating’ is obviously premised on a
    disclaimer theory.” Roku Br. 43. However, we are not di-
    rected to a disclaimer, and none is cited. A disclaimer of a
    legal right should be clear and explicit. See Trivascular,
    Inc. v. Samuels, 
    812 F.3d 1056
    , 1063–64 (Fed. Cir. 2016)
    (“The party seeking to invoke prosecution history dis-
    claimer bears the burden of proving the existence of a ‘clear
    Case: 21-1992    Document: 43     Page: 14    Filed: 08/18/2023
    14                 UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.
    and unmistakable’ disclaimer that would have been evi-
    dent to one skilled in the art.”).
    The Board found that both Mishra and Rye disclose the
    “generating” limitation, Board Op. at *15, *21, and that
    Caris generates a key code signal by identifying the corre-
    sponding code from a look-up table, id. at *27. Substantial
    evidence supports the Board’s findings that Mishra, Rye,
    and Caris disclose generating a key code by converting or
    translating a received signal, as the term is used in claims
    1–4, 6, 8, 9, and 22–25 of the ’642 patent and claims 2 and
    3 of the ’389 patent. We conclude that the Board correctly
    applied these references to the claim term “generating a
    key code.”
    B
    The term “means for receiving a key code”
    The “means” limitation, “means for receiving a key
    code from said RF receiver and for sending said key code to
    said IR transmitter such that said key code is modulated
    onto an IR carrier signal,” appears in claims 12–15 of the
    ’389 patent. UEI argues that the Board erred in holding
    these claims obvious based on Mishra in combination with
    Dubil, and also based on Caris in combination with Skerlos
    and Yazolino (
    U.S. Patent No. 5,329,370
    ). UEI Br. 3–4.
    UEI states that the Board’s construction of the “means”
    limitation is legally erroneous, and that Roku’s combina-
    tions of references does not disclose this limitation under
    the proper construction. 
    Id.
    The means-plus-function provision of Title 35 (previ-
    ously § 112(6)) states:
    § 112(f) Element in Claim for a Combina-
    tion.—
    An element in a claim for a combination may be ex-
    pressed as a means or step for performing a speci-
    fied function without the recital of structure,
    Case: 21-1992    Document: 43        Page: 15   Filed: 08/18/2023
    UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.                    15
    material, or acts in support thereof, and such claim
    shall be construed to cover the corresponding struc-
    ture, material, or acts described in the specification
    and equivalents thereof.
    This provision “allows a patentee to recite a function to be
    performed as a claim limitation rather than reciting struc-
    ture or materials for performing that function.” Omega
    Eng’g, Inc. v. Raytek Corp., 
    334 F.3d 1314
    , 1321 (Fed. Cir.
    2003). Analysis of a means-plus-function limitation follows
    an established protocol:
    The construction of a means-plus-function limita-
    tion follows a two-step approach. First, we must
    identify the claimed function, staying true to the
    claim language and the limitations expressly re-
    cited by the claims. Once the functions performed
    by the claimed means are identified, we must then
    ascertain the corresponding structures in the writ-
    ten description that perform those functions. A dis-
    closed structure is corresponding “only if the
    specification or the prosecution history clearly
    links or associates that structure to the function re-
    cited in the claim.” In other words, the structure
    must be necessary to perform the claimed function.
    
    Id.
     (internal citations omitted).
    The parties agree that the claimed function is “receiv-
    ing a key code from said RF receiver and for sending said
    key code to said IR transmitter such that said key code is
    modulated onto an IR carrier signal.” Board Op. (’389 pa-
    tent) at *12. Construing the recited means, the Board
    adopted Roku’s proposed construction: “a microcontroller
    that performs the algorithm of receiving a key code from an
    RF receiver that has received a first key code signal and
    translating the key code so that the key code is modulated
    onto an infrared carrier signal resulting in a second key
    code signal.” 
    Id. at *14
    . This construction is consistent
    with the specification’s description of the remote control
    Case: 21-1992     Document: 43     Page: 16    Filed: 08/18/2023
    16                  UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.
    that performs the receiving and sending functions. As §
    112(f) provides, the claim scope is limited to the structure
    in the specification and its equivalents. See Aristocrat
    Techs. Austl. Pty v. Int’l Game Tech., 
    521 F.3d 1328
    , 1333
    (Fed. Cir. 2008).
    The Board determined that the ’389 patent describes
    the algorithm for the claimed sending and receiving func-
    tions, stating that “Petitioner’s proposed structure goes be-
    yond a mere restatement of the function by including
    specific reference to key code signals and translation of the
    key code. Petitioner supports its proposal by citing to col-
    umn 5, lines 45–59, of the ’389 patent, which makes specific
    reference to the first and second key code signals, as well
    as to ‘translating the communicated key code.’” Board Op.
    (’389 patent) at *13. The specification of the ’389 patent
    illustrates:
    Next (step 104), an RF transmitter 20 of
    key code generator device 12 transmits first key
    code signal 19 in the form of an RF transmission to
    an RF receiver 21 on remote control device 11.
    Next (step 105), remote control device 11
    receives first key code signal 19 and relays the key
    code communicated by first key code signal 19 to
    VCR 13 in the form of a second key code signal 22.
    Remote control device 11 is a slave to key code gen-
    erator device 12. Remote control device 11 relays
    the key code by receiving first key code signal 19 in
    RF form and translating the communicated key
    code so that the key code is modulated onto a sec-
    ond carrier signal resulting in second key code sig-
    nal 22. In this example, the second carrier signal
    is an infrared signal with a frequency in the range
    between three hundred gigahertz and three hun-
    dred terahertz.
    ’389 patent, col. 5, ll. 45–59. The Board correctly concluded
    that the algorithm for performing the claimed “receiving”
    Case: 21-1992    Document: 43      Page: 17    Filed: 08/18/2023
    UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.                  17
    and “sending” functions is disclosed, for this passage de-
    scribes the claimed means by which the remote control mi-
    crocontroller carries out the function of receiving a key code
    from the RF receiver and sending the code to the IR trans-
    mitter.
    Roku correctly states that “the Board’s articulation of
    the claimed structure, which includes only the particular
    algorithm required to perform the claimed function, is
    faithful to the specification’s own description and con-
    sistent with the extrinsic evidence of record.” Roku Br. 55.
    See Univ. of Pitt. of Commonwealth Sys. Of Higher Educ.
    v. Varian Med. Sys., Inc., 
    561 F. App’x 934
    , 941 (Fed. Cir.
    2014) (“The district court properly located the disclosure of
    an algorithm that covered what was necessary to perform
    the claimed function . . . and nothing more . . . . The algo-
    rithm need only include what is necessary to perform the
    claimed function.”).
    UEI argues that “[t]he Board’s finding that Mishra in
    combination with Dubil and Caris in combination with
    Skerlos and Yazolino disclose the Means Limitation should
    also be reversed because it is based on a legally erroneous
    construction of the structure of the Means Limitation as ‘a
    microcontroller that performs the algorithm of receiving a
    key code from an RF receiver that has received a first key
    code signal and translating the key code so that the key
    code is modulated onto an infrared carrier signal resulting
    in a second key code signal.’” UEI Br. 58.
    The Board found that the microcontroller of Mishra
    controls reception of a key code from an RF transceiver and
    transmits the key code with an IR transmitter. And, in
    light of Dubil’s modulating key code techniques, the Board
    concluded that Misha thus teaches the “means for receiv-
    ing a key code.” See Board Op. (’389 patent) at *27 (“For the
    ‘means for receiving a key code,’ Petitioner identifies the
    microcontroller, discussed above in connection with de-
    pendent claim 10, which controls reception of a key code
    Case: 21-1992     Document: 43      Page: 18     Filed: 08/18/2023
    18                  UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.
    from an RF transceiver, and transmits the key code with
    an IR transmitter. Because this identification is sufficient
    under our adopted construction of the ‘means for receiving
    a key code,’ and because Petitioner makes explicit refer-
    ence to its analysis of modulating key codes in light of Du-
    bil, we conclude that Petitioner makes a sufficient
    showing.” (internal citations omitted)).
    The Board made a similar finding regarding the micro-
    controller of the means limitations for Caris in combination
    with Skerlos and Yazolino, stating:
    In addition to Caris and Skerlos, Petitioner relies
    on Yazolino in addressing limitations of claims that
    recite a “microcontroller” in some form . . . . [Roku’s
    expert] testifies that, in Petitioner’s proposed com-
    bination of Caris and Skerlos, the modulation de-
    scribed in Skerlos “would be performed by a
    microcontroller in the remote control,” but that
    “Caris does not explicitly describe these opera-
    tional details.” Petitioner accordingly reasons that
    a person of ordinary skill in the art “would have
    known to look to references, such as Yazolino,
    which explicitly describes the circuitry of a remote
    control such as the one disclosed by Caris.” In light
    of Petitioner’s evidence, we find this reasoning,
    which is supported by rational underpinning, suffi-
    cient to effect the combination of those teachings
    with those of Caris and Skerlos.
    Board Op. (’389 patent) at *31 (internal citations omitted).
    These findings are supported by substantial evidence,
    particularly the disclosures in the cited references as dis-
    cussed above. These findings support the Board’s construc-
    tion. On this construction, UEI does not dispute that
    Mishra in combination with Dubil, and Caris in combina-
    tion with Skerlos and Yazolino, disclose the “means” limi-
    tation. We affirm the Board’s determinations regarding
    this term.
    Case: 21-1992     Document: 43    Page: 19    Filed: 08/18/2023
    UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.                   19
    C
    The term “processing device”
    The Board found that it would have been obvious to a
    skilled artisan that Caris’ set top box (STB) would include
    a processing device as recited in the processing device lim-
    itation in claims 1–5 of the ’325 patent. Board Op. (’325
    patent) at *20. UEI states that the Board erred. UEI ar-
    gues that “Claim 1 of the ’325 patent recites a ‘processing
    device’ that performs the steps or functions of ‘generat[ing]
    a key code,’ ‘format[ting] the key code,’ and ‘transmit[ting]
    the formatted key code.’” UEI Br. 62. UEI states that
    “Roku conceded that Caris does not disclose that its set-top
    box (“STB”) has a ‘processing device.’” 
    Id.
    UEI states that the Board offered no reasoning to sup-
    port its conclusion that it would have been obvious to mod-
    ify Caris to include a processing device that performs the
    functions of generating, formatting, and transmitting. 
    Id.
    at 62–63. Roku responds with the testimony of its expert,
    Dr. Russ, that “set-top boxes containing such devices for
    processing received commands and transmitting key codes
    were well-known in the art.” Roku Br. 65. Dr. Russ stated:
    Caris describes the functionality of an STB as
    well as a receiver and a transmitter but does not
    explicitly illustrate the processing device of the
    STB that is used for generating a key code and
    transmitting the key code as will be further de-
    scribed below. However, in view of the STB func-
    tionality described in Caris, a POSA would have
    found it obvious that this functionality would have
    been performed using a processing device coupled
    to the receiver and the transmitter. STBs typically
    included processing devices such as processors or
    microcontrollers that controlled the functionality of
    the STBs.
    Case: 21-1992     Document: 43      Page: 20   Filed: 08/18/2023
    20                  UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.
    ***
    A POSA would have understood that STBs
    would receive a command from a remote control
    and use a processing device to interpret the com-
    mand and identify a corresponding key code. The
    STBs would also identify potential parameters,
    such as modulation and timing parameters, used to
    transmit the key code to another device. A pro-
    cessing device would be used to access memory and
    retrieve the corresponding key code as well as per-
    form the modulation of the key code for transmis-
    sion. Thus, a POSA would have understood that
    Caris’ STB would include a processing device in or-
    der to perform the functions described in Caris.
    Russ Decl. ¶¶ 173, 176 (Appx2334, 2336) (internal citations
    omitted). Dr. Russ provided 
    U.S. Patent No. 6,909,471
    (Bayley), as a reference, and stated: “As illustrated in Bay-
    ley, processing devices in STBs were well-known prior to
    the ’325 patent and executed instructions in memory to re-
    ceive commands and transmit corresponding control
    codes.” 
    Id.
     at ¶¶ 174–75 (Appx2334–36). The Board stated:
    We credit Dr. Russ’ testimony and are per-
    suaded by Petitioner’s argument and the cited evi-
    dence that, in view of what was well-known to
    ordinarily skilled artisans, it would have been ob-
    vious to a person of ordinary skill in the art that
    Caris’s STB would include a processing device that
    performs the claimed functions, including the func-
    tions to “generate a key code,” “format the key
    code,” and “transmit the formatted key code” and
    that for Caris to perform the claimed functions, the
    STB would include memory storing instructions ex-
    ecuted by the processing device.
    Board Op. at *20.
    Case: 21-1992     Document: 43      Page: 21   Filed: 08/18/2023
    UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.                 21
    We conclude that substantial evidence, including ex-
    pert testimony and the cited references, supports the
    Board’s findings, and that the Board correctly construed
    the processing device limitation.
    D
    The term “timing information”
    The parties also debate the “timing information” limi-
    tation wherein key code/codeset comprises timing/time in-
    formation. This term is present in claims 4, 9, 23, and 25
    of the ’642 patent and claims 1–5 of the ’325 patent.
    UEI states that substantial evidence does not support
    the Board’s findings that: “(i) Mishra or Rye in combination
    with Dubil and Caris in combination with Skerlos disclose
    the limitation ‘wherein said key code . . . comprises timing
    information’ in challenged claims 4 and 23 of the 642 pa-
    tent; (ii) that Mishra or Rye in combination with Dubil dis-
    closes the limitation ‘wherein said codeset comprises
    timing information’ in challenged claims 9 and 25 of the
    642 patent; and (iii) Caris in combination with Dubil dis-
    closes the limitation ‘wherein the codeset further comprises
    time information’ in challenged claim 1 of the [’]325 pa-
    tent.” UEI Br. 51.
    Claim 4 of the ’642 patent is representative:
    4. The method of claim 1, wherein said key code
    comprises a binary number and timing infor-
    mation, and wherein said timing information de-
    fines how said binary number is modulated in (c)
    onto said carrier signal.
    ’642 patent, col. 10, ll. 36–39.
    UEI argues that the Board simply “adopted Roku’s po-
    sition that Dubil and Skerlos disclose ‘wherein said key
    code comprises . . . timing information’ because the alleged
    timing information in Dubil and Skerlos would purportedly
    Case: 21-1992     Document: 43     Page: 22    Filed: 08/18/2023
    22                  UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.
    be ‘used to modulate a binary number onto a carrier fre-
    quency.’” UEI Br. 51. UEI states that:
    Even if it is true that the timing information in Du-
    bil and Skerlos is used to modulate a key code or
    binary number onto a carrier frequency, this has no
    bearing on whether the key code or codeset com-
    prises timing information, as claimed. Indeed, the
    claims of the Challenged Patents expressly distin-
    guish between a key code or codeset that “com-
    prises timing information,” and using timing
    information to modulate a key code or binary num-
    ber onto a carrier frequency.
    UEI Br. 52–53 (emphases original).
    The Board found that Dubil discloses timing parame-
    ters such as “duty cycle,” “repetition time,” and “on/off
    times of the signal.” Board Op. at *25. Roku’s expert ex-
    plained that Dubil’s “on/off times” define timing for the bi-
    nary numbers of the key codes, wherein “the amount of
    ‘on/off’ time used for each digital one or digital zero would
    describe timing information . . . to define how the binary
    key code would be modulated onto a carrier signal.” Russ
    Decl. ¶ 137 (Appx1091).
    The Board found that a skilled artisan would have con-
    sidered Dubil’s and Skerlos’ teaching of timing information
    “as part of considering the teachings for wireless transmis-
    sion of key codes.” Board Op. at *19, *29. This conclusion
    was supported by the expert testimony that “[i]f a POSA
    did not already understand the formatting of a key code, a
    POSA would look to references” such as Dubil and Skerlos,
    which “describ[e] the format as well as how to transmit the
    key codes using a carrier signal.” Russ Decl. ¶ 139
    (Appx1092). Dr. Russ declared:
    A POSA would understand that the Skerlos
    teaches a key code comprising the timing infor-
    mation because Skerlos uses this the timing
    Case: 21-1992      Document: 43    Page: 23    Filed: 08/18/2023
    UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.                   23
    information described in Skerlos to modulate the
    “bits of coded information” onto a carrier signal. As
    previously explained . . ., this type of modulation
    was well-known and the inclusion of timing infor-
    mation in a key code to modulate the key code onto
    a carrier signal was well-known.
    
    Id. at ¶230
     (Appx1150).
    We conclude that the Board correctly construed the
    “timing information” limitation to conform with existing
    knowledge such as is shown in the Dubil and Skerlos refer-
    ences, which describe the format and transmission of key
    codes using a carrier signal.
    E
    The combination of references
    The Board found that Mishra, Rye, and Caris describe
    wirelessly transmitting a key code signal from a set-top box
    to a remote control. The Board found that a person of ordi-
    nary skill in this field would have been motivated to com-
    bine known modulation techniques with known wireless
    transmission, for the references are in closely related fields
    of endeavor, and the Board’s conclusion was supported by
    expert testimony and citations to relevant references.
    The parties repeat the debate on this appeal. We con-
    clude that substantial evidence supports the Board’s find-
    ings concerning the combination of references, in turn
    supporting the Board’s conclusion that it would have been
    obvious to a skilled artisan to combine Dubil’s and Skerlos’
    modulation and timing information with the wireless key
    code transmission of Mishra, Rye, and Caris. This conclu-
    sion is founded on the content of the references and the ex-
    pert testimony, and is in accordance with law. We affirm
    the Board’s holding that it would have been obvious to mod-
    ulate the Mishra/Rye/Caris codes as in Dubil and Skerlos.
    Case: 21-1992   Document: 43     Page: 24    Filed: 08/18/2023
    24                UNIVERSAL ELECTRONICS, INC. v. ROKU, INC.
    CONCLUSION
    We have considered all the arguments concerning
    these three patents and affirm the Board’s decisions of in-
    validity of the claims at issue.
    AFFIRMED