Interdigital Communications v. Zte Corporation , 711 F. App'x 998 ( 2017 )


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  •        NOTE: This disposition is nonprecedential.
    United States Court of Appeals
    for the Federal Circuit
    ______________________
    INTERDIGITAL COMMUNICATIONS, INC., A
    DELAWARE CORPORATION, INTERDIGITAL
    TECHNOLOGY CORPORATION, A DELAWARE
    CORPORATION, IPR LICENSING, INC., A
    DELAWARE CORPORATION, INTERDIGITAL
    HOLDINGS, INC., A DELAWARE CORPORATION,
    Plaintiffs-Appellees
    v.
    ZTE CORPORATION, A CHINESE CORPORATION,
    ZTE (USA) INC., A NEW JERSEY CORPORATION,
    Defendants-Appellants
    ______________________
    2016-2362
    ______________________
    Appeal from the United States District Court for the
    District of Delaware in No. 1:13-cv-00009-RGA, Judge
    Richard G. Andrews.
    ______________________
    Decided: November 3, 2017
    ______________________
    MAXIMILIAN A. GRANT, Latham & Watkins LLP,
    Washington, DC, argued for plaintiffs-appellees. Also
    represented by GABRIEL BELL, RICHARD P. BRESS,
    MICHAEL J. GERARDI.
    2        INTERDIGITAL COMMUNICATIONS    v. ZTE CORPORATION
    CHARLES M. MCMAHON, McDermott Will & Emery
    LLP, Chicago, IL, argued for defendants-appellants. Also
    represented by BRIAN ANDREW JONES; NATALIE A.
    BENNETT, JAY H. REIZISS, Washington, DC.
    ______________________
    Before PROST, Chief Judge, LOURIE, and TARANTO, Circuit
    Judges.
    TARANTO, Circuit Judge.
    InterDigital Communications, Inc.; InterDigital
    Technology Corp.; IPR Licensing, Inc.; and InterDigital
    Holdings (collectively, InterDigital) brought this suit
    against ZTE Corp. and ZTE (USA) Inc. (collectively, ZTE)
    in the United States District Court for the District of
    Delaware. InterDigital alleged that ZTE was infringing
    U.S. Patent Nos. 7,190,966 and 7,286,847, which, as
    relevant here, claim a specified apparatus for wireless
    communications. InterDigital and ZTE have litigated
    these patents and related ones before the International
    Trade Commission in at least three proceedings, two of
    which resulted in written decisions from this court: Inter-
    Digital Communications, LLC v. International Trade
    Commission (InterDigital I), 
    690 F.3d 1318
     (Fed. Cir.
    2012), and InterDigital Communications, LLC v. Interna-
    tional Trade Commission (InterDigital II), 601 F. App’x
    972 (Fed. Cir. 2015).
    In this case, a jury found ZTE liable for infringement
    of the ’966 and ’847 patents, and the district court denied
    ZTE’s post-trial motion for judgment of noninfringement
    as a matter of law. ZTE appeals a key claim construction
    adopted by the district court as well as the court’s denial
    of its post-trial motion. We have jurisdiction under 
    28 U.S.C. § 1295
    (a)(1). We affirm.
    INTERDIGITAL COMMUNICATIONS       v. ZTE CORPORATION        3
    I
    A
    The technology described in the ’966 and ’847 patents
    is set forth in detail in our earlier decision addressing
    those patents, InterDigital I, 690 F.3d at 1320–23. Here,
    we cover only the aspects relevant to the issues on appeal.
    The ’966 and ’847 patents describe how to reduce
    “power overshoot” when establishing a connection be-
    tween a “subscriber unit,” such as a cell phone, and a base
    station in a code division multiple access (CDMA) wireless
    communication system. ’966 patent, col. 3, lines 32–40. 1
    In order to set up a two-way communication link, the
    transmitter in a cell phone sends a signal to the base
    station, which the base station can detect if the signal is
    transmitted at a sufficient power level. Col. 2, lines 50–
    52. But the power level required to be detected is not
    known in advance of attempting to make the connection.
    Col. 2, lines 45–46. To the extent that the transmitter
    uses a power level that overshoots the threshold detection
    level, the communication conducted at that unnecessarily
    high power level will decrease system capacity, may
    interfere with communications between other cell phones
    and the base station, and may even cause dropped calls.
    Col. 2, lines 23–28, 46–50; see also col. 5, lines 63–67; col.
    6, lines 5–6.
    The specification describes two embodiments that use
    a “power ramp-up” process to minimize power overshoot.
    Col. 3, line 23. In the first embodiment, a transmitter in
    the cell phone transmits a code called an “access code” to
    the base station. Col. 6, lines 7–10, 19–20, & Fig. 4. “The
    access code is a known spreading code transmitted from
    1   The ’966 and ’847 patent share a common specifi-
    cation. All patent citations hereafter are to the ’966
    patent, unless otherwise indicated.
    4         INTERDIGITAL COMMUNICATIONS     v. ZTE CORPORATION
    [the cell phone] to the base station during initiation of
    communications and power ramp-up.” Col. 6, lines 20–23
    (internal references omitted). The access code is first
    transmitted at a very low power below any possible detec-
    tion level, and then successively transmitted at increasing
    levels of power. Col. 6, lines 1–5 & Fig. 5. Once the
    access code is transmitted at a power level at or above
    that of the threshold detection level, the base station
    “search[es] through all possible phases (time shifts) of the
    access code . . . in order to find the correct phase.” Col. 6,
    lines 23–26 (internal references omitted). The power-
    ramp up continues while the base station engages in this
    search, called the “detection process.” Col. 6, lines 26–27.
    After detecting the correct phase of the access code, the
    base station sends “an access code detection acknowl-
    edgement signal” back to the cell phone. Col. 6, lines 59–
    67. The transmitter and base station then establish a
    closed power loop at the power level the transmitter has
    reached at the time of the phase detection, and “call setup
    signaling is performed” for “the two-way communication
    link.” Col. 7, lines 2–5. By proceeding in this manner, the
    communication link is closer to the threshold detection
    level—and there is less interference and fewer dropped
    calls—than if the transmitter had used a higher power
    level. Col. 6, lines 1–6.
    The power level reached in this first embodiment may
    still be higher than necessary. Even after the access code
    reaches the threshold detection level, the base station
    requires time to “search through all possible phases (time
    shifts) of the access code . . . in order to find the correct
    phase.” Col. 6, lines 23–26. The amount of time required
    to detect the correct phase depends on the length of the
    access code; “[t]he longer the access code, the longer it
    takes for the base station to search through the phases
    and acquire the correct phase.” Col. 6, lines 27–29 (inter-
    nal references omitted); see also col. 7, lines 18–25. And
    during the time the base station is searching for the
    INTERDIGITAL COMMUNICATIONS   v. ZTE CORPORATION          5
    correct phase, the cell phone transmitter continues to
    ramp up the power level at which it transmits the access
    code. See col. 7, lines 26–34. The power level being used
    when the base station completes its phase detection,
    which is the level at which communications then occur,
    thus exceeds the minimum threshold detection level,
    which is the level at which the phase search began. See
    col. 7, lines 18–34 & Fig. 5.
    The second embodiment, expressly deemed “the pre-
    ferred embodiment,” further reduces power overshoot.
    Col. 7, lines 41–44; compare Fig. 5 with Fig. 7. In the
    second embodiment, rather than successively sending the
    access code during initial power ramp-up, the transmitter
    sends a “short code,” defined as “a sequence for detection
    by the base station which has a much shorter period than
    a conventional spreading code.” Col. 3, lines 23–25.
    Because the short code is in fact short, the base station
    needs less time to search for the correct phase and detect
    the signal than in the first embodiment (for the longer
    access code), thus decreasing the amount of power ramp
    up that occurs during the search time. See col. 1, lines
    28–31 (“[T]he transmission of short codes from [cell
    phones] to a base station . . . reduce[s] the time required
    for the base station to detect the signal from a [cell
    phone].”); col. 8, lines 7–9 (“[T]he short code is much
    smaller” and “can be chosen to be any length that is
    sufficiently short to permit quick detection.”). The base
    station sends an acknowledgment signal, after which the
    cell phone begins transmitting the access code at a much
    slower ramp-up rate, starting at the power level at which
    the short code was detected. Col. 8, lines 32–42 & Figs.
    6A, 6B, 11A, 11B. Once the base station detects the
    access code, the base station sends another acknowledg-
    ment signal, and the two-way communication link is set
    up at that power level. Col. 8, line 66 through col. 9, line
    6.
    6         INTERDIGITAL COMMUNICATIONS   v. ZTE CORPORATION
    B
    At issue on appeal is ZTE’s liability for infringement
    of independent claim 1 and dependent claims 3, 6, 8, 9,
    and 11 of the ’966 patent, and of independent claims 3
    and 5 of the ’847 patent. Claim 1 of the ’966 patent and
    claim 3 of the ’847 patent are representative: 2
    1. A wireless code division multiple access (CDMA)
    subscriber unit comprising:
    a transmitter configured such that, when the sub-
    scriber unit is first accessing a CDMA network
    and wants to establish communications with a
    base station associated with the network over
    a communication channel to be indicated by
    the base station, the transmitter successively
    transmits signals until the subscriber unit re-
    ceives from the base station an indication that
    a transmitted one of the signals has been de-
    tected by the base station, wherein each
    transmission of one of the signals by the
    transmitter is at an increased power level with
    respect to a prior transmission of one of the
    signals;
    the transmitter further configured such that the
    transmitter transmits to the base station a
    message indicating to the base station that the
    subscriber unit wants to establish the commu-
    nication with the base station over the com-
    munication channel to be indicated by the base
    station, the message being transmitted only
    subsequent to the subscriber unit receiving the
    indication;
    2   On appeal, ZTE does not make separate argu-
    ments as to the dependent claims or claim 5 of the ’847
    patent.
    INTERDIGITAL COMMUNICATIONS   v. ZTE CORPORATION            7
    wherein each of the successively transmitted sig-
    nals and the message are generated using a
    same code; and
    wherein each of the successively transmitted sig-
    nals is shorter than the message.
    Col. 10, line 62 through col. 11, line 19 (emphases added).
    3. A wireless code division multiple access (CDMA)
    subscriber unit comprising:
    a circuit configured to synchronize to a pilot signal
    transmitted by a base station associated with a
    CDMA network wherein, if the circuit becomes
    unsynchronized to the pilot signal during an
    idle period of the subscriber unit, the circuit is
    further configured to re-synchronize to the pi-
    lot signal;
    a transmitter configured such that, when the sub-
    scriber unit is first accessing the CDMA net-
    work, the transmitter successively transmits
    signals generated using a portion of a code un-
    til the subscriber unit receives from the base
    station an indication that a transmitted one of
    the signals has been detected by the base sta-
    tion, wherein each transmission of one of the
    signals by the transmitter, other than a
    transmission of a first one of the signals, is at
    an increased power level with respect to a prior
    transmission of another one of the signals;
    the transmitter further configured such that, sub-
    sequent to the subscriber unit receiving the in-
    dication, the transmitter transmits a signal
    generated using a remainder of the code;
    wherein prior to receiving the indication, the sub-
    scriber unit is not uniquely identified to the
    base station.
    8         INTERDIGITAL COMMUNICATIONS    v. ZTE CORPORATION
    ’847 patent, col. 11, line 53 through col. 12, line 9 (empha-
    sis added).
    II
    A
    The primary dispute on appeal is the proper construc-
    tion of the claim term “successively transmits signals” or
    “successively transmitted signals.” The district court
    construed the term “code” as a “sequence of chips or bits,”
    and it construed the disputed term “successively trans-
    mits signals; successively transmitted signals” as “succes-
    sively [transmits / transmitted] sequences of chips or
    bits”—i.e., successively transmits / transmitted sequences
    of code. InterDigital Commc’ns, Inc. v. ZTE Corp., No.
    1:13-cv-00009, 
    2014 WL 1620733
    , at *2 (D. Del. Apr. 22,
    2014). Because the district court did not make any factu-
    al findings based on extrinsic evidence in the course of
    construing the term “successively transmits signals;
    successively transmitted signals,” we review the district
    court’s claim construction de novo. Teva Pharms. USA,
    Inc. v. Sandoz, Inc., 
    135 S. Ct. 831
    , 841 (2015); Cardsoft,
    LLC v. VeriFone, Inc., 
    807 F.3d 1346
    , 1350 (Fed. Cir.
    2015).
    ZTE contends that the proper construction of “succes-
    sively transmitted signals” is “successively transmitted
    sequences of chips or bits not modulated by a data signal.”
    ZTE Br. 40. It relies on two premises—first, that “succes-
    sively transmitted signals” refers only to the short codes
    described in the specification; second, that the short codes
    are not modulated by a data signal, which means that the
    short codes do not carry data. See InterDigital I, 690 F.3d
    at 1321, 1326 (explaining that spreading codes “carry”
    data by modulating, or modifying, a baseband data sig-
    nal). We reject ZTE’s first premise and therefore its claim
    construction.
    INTERDIGITAL COMMUNICATIONS     v. ZTE CORPORATION           9
    The “successively transmitted signals” in the claims
    are the codes sent by the cell phone transmitter during
    the initial power ramp-up phase. The specification de-
    scribes two embodiments in great detail: one embodiment
    in which the successively transmitted signals are the
    access codes, col. 6, line 1 through col. 7, line 40 & Figs. 4,
    5, and a second, preferred embodiment in which the
    successively transmitted signals are the short codes, col.
    7, line 41 through col. 9, line 35 & Figs. 6A, 6B, 7; col. 10,
    lines 10–53 & Figs. 11A, 11B. The specification expressly
    indicates that the invention is not limited to the preferred
    embodiment. Col. 10, lines 54–57 (“Although the inven-
    tion has been described in part by making detailed refer-
    ence to the preferred embodiment, such detail is intended
    to be instructive rather than restrictive.”). Although the
    second embodiment is preferred and highlighted in the
    background and summary of the invention sections, col. 1,
    lines 27–31; col. 3, lines 19–23, we see no basis on which
    to limit the claims to that embodiment when the plain
    language of the claims in these patents, as well as the
    specification, encompass both. Indeed, ZTE makes no
    substantial argument based on the claim language and
    specification for limiting the claim phrase at issue to the
    short codes. 3
    ZTE relies instead on our earlier decision, InterDigital
    II, 601 F. App’x 972, involving U.S. Patent Nos. 7,706,830
    and 8,009,636—which, though they have materially the
    3   ZTE does not, for instance, argue that the claim
    language “each of the successively transmitted signals is
    shorter than the message” supports limiting the “succes-
    sively transmitted signals” to short codes. In fact, ZTE
    admits that even in the first embodiment, after the base
    station detects the successively transmitted access code,
    the cell phone then “transmits a ‘message’ to the base
    station.” ZTE Br. 10 (citing Fig. 4 (box 116)).
    10        INTERDIGITAL COMMUNICATIONS    v. ZTE CORPORATION
    same specification as the ’966 and ’847 patents, have
    notably different claims. In InterDigital II, the Interna-
    tional Trade Commission first construed a phrase in the
    ’830 and ’636 patents, “successively sends [or sent] trans-
    missions,” as “transmits to the base station, one after the
    other, codes that are shorter than a regular length code.”
    Id. at 977. The Commission then “conclud[ed] that the
    patents ‘disclose that the codes successively transmitted
    during the random access process (i.e., the short codes)
    are neither modulated with data, nor used to modulate
    data.’” Id. (quoting Commission’s decision).
    The first step in the Commission’s conclusion in In-
    terDigital II is the one relevant here. The problem for
    ZTE, however, is that this court in InterDigital II had no
    occasion to rule on the correctness of the Commission’s
    conclusion at that step, i.e., that the successively trans-
    mitted signals were only short codes, even in the context
    of the two patents at issue in InterDigital II. Although
    InterDigital disputed that point before the Commission,
    InterDigital did not dispute it before this court on appeal.
    This court therefore assumed that the phrase in the
    claims of those patents was limited to short codes, with-
    out independent claim-construction analysis on the point;
    and based on that assumption, it treated the claims at
    issue as dealing with the preferred (short code + access
    code) embodiment, not the first (access code only) embod-
    iment. The question the court decided involved only the
    Commission’s second step—whether “‘the Commission
    erred in limiting the successively transmitted short codes
    to codes not modulated by data.’” InterDigital II, 601 F.
    App’x at 977 (quoting InterDigital’s brief) (internal quota-
    tion marks omitted).
    Contrary to ZTE’s contention, therefore, InterDigital
    II does not establish an answer to the issue presented
    here, which was not contested or decided there. See, e.g.,
    Automated Merchandising Sys., Inc. v. Lee, 
    782 F.3d 1376
    ,
    1381 (Fed. Cir. 2015); Lumbermens Mut. Cas. Co. v.
    INTERDIGITAL COMMUNICATIONS    v. ZTE CORPORATION          11
    United States, 
    654 F.3d 1305
    , 1317 n.10 (Fed. Cir. 2011);
    United States v. Cty. of Cook, Ill., 
    170 F.3d 1084
    , 1088
    (Fed. Cir. 1999). The court in InterDigital II did not
    decide, but merely assumed, the issue of restriction to the
    short-code embodiment, even as to the phrase in the
    particular claims in the two patents at issue in InterDigi-
    tal II. Moreover, the claims in the present case are differ-
    ent from those in InterDigital II: surrounding claim
    language can affect the interpretation of a claim phrase,
    and the surrounding language differs between the Inter-
    Digital II claims and the claims at issue here. ZTE has
    not made any showing of the irrelevance of those differ-
    ences. 4 For those reasons, InterDigital II does not decide
    whether “successively transmitted signals” in the claims
    of the patents at issue here are limited to short codes to
    the exclusion of the first embodiment.
    Nor is InterDigital judicially estopped from arguing in
    this case that the disputed term is not limited to short
    codes. Judicial estoppel applies “where a party assumes a
    certain position in a legal proceeding, and succeeds in
    maintaining that position”; thereafter, “he may not . . . ,
    simply because his interests have changed, assume a
    contrary position, especially if it be to the prejudice of the
    party who has acquiesced in the position formerly taken
    by him.” Davis v. Wakelee, 
    156 U.S. 680
    , 689 (1895);
    4   For example, claim 1 of the ’830 patent, which In-
    terDigital designated as the representative claim, Br. of
    Appellants, InterDigital II, No. 14-1176, 
    2014 WL 1573071
    , at *9 (Fed. Cir., filed Apr. 7, 2014), and which
    was the focus of this court’s discussion in InterDigital II,
    requires that “at least two of the successively sent trans-
    missions are produced using different sequences of chips,”
    ’830 patent, col. 11, lines 8–9, which appears to corre-
    spond to a specification passage limited to the preferred
    embodiment, 
    id.,
     col. 9, lines 8–29.
    12        INTERDIGITAL COMMUNICATIONS    v. ZTE CORPORATION
    accord New Hampshire v. Maine, 
    532 U.S. 742
    , 749
    (2001). Here, it is true that InterDigital stated in its
    opening brief in InterDigital II that “InterDigital agrees
    that the only disclosure in the specification of ‘successive-
    ly sent transmissions’ are ‘short codes.’” Br. of Appel-
    lants, InterDigital II, No. 14-1176, 
    2014 WL 1573071
    , at
    *24 (Fed. Cir., filed Apr. 7, 2014). But, regardless of
    whether that statement must be read as contrary to
    InterDigital’s position in this appeal, the statement does
    not support judicial estoppel at least for the reason that
    the statement did not lead to success by InterDigital.
    This court proceeded on the premise accepted on appeal
    by InterDigital and ruled against InterDigital’s challenge
    on appeal. Judicial estoppel therefore does not apply.
    ZTE also suggests that, before appealing to this court
    in InterDigital II, InterDigital admitted before the Com-
    mission that “successively sent transmissions” referred
    only to short codes. Not so. InterDigital disputed the
    matter before the administrative law judge and the Com-
    mission. And the testimony of InterDigital’s expert before
    the Commission that “the repeated transmissions of the
    short code are the successively sent transmissions” indi-
    cates that short codes fall within the scope of that term,
    not that the scope of the term is limited to short codes.
    J.A. 10288. 5
    We conclude that “successively transmit / transmitted
    signals” refers not only to the short codes of the preferred
    embodiment but also to the access codes of the first em-
    5
    ZTE highlights several other purported admis-
    sions by InterDigital that relate to InterDigital’s second
    premise—i.e., that the short codes in the preferred embod-
    iment carry data—but that do not support ZTE’s argu-
    ment as to the first premise—i.e., that the disputed term
    is limited to short codes, as in the preferred embodiment.
    INTERDIGITAL COMMUNICATIONS       v. ZTE CORPORATION        13
    bodiment. ZTE did not argue on appeal that the access
    codes of the first embodiment do not modulate data, and
    has therefore waived the argument that its proposed
    limitation, “not modulated by a data signal,” would be
    appropriate even if the disputed term is construed as not
    limited to the preferred embodiment. For those reasons,
    we affirm the district court’s construction.
    B
    We review de novo the district court’s denial of judg-
    ment as a matter of law, “viewing the record in the light
    most favorable to . . . the verdict winner, and drawing all
    reasonable inferences in [the winner’s] favor.” Pitts v.
    Delaware, 
    646 F.3d 151
    , 155 (3d Cir. 2011). Judgment as
    a matter of law is permitted only if “there is insufficient
    evidence from which a jury could reasonably find liabil-
    ity.” Lightning Lube, Inc. v. Witco Corp., 
    4 F.3d 1153
    ,
    1166 (3d Cir. 1993). “In determining whether the evi-
    dence is sufficient to sustain liability, the court may not
    weigh the evidence, determine the credibility of witnesses,
    or substitute its version of the facts for the jury’s version.”
    Id.; accord Pitts, 
    646 F.3d at 155
    .
    Many of the facts are undisputed. ZTE agrees that its
    products comply with the 3rd Generation Partnership
    Project (3GPP) telecommunications standard. According
    to that standard, the cell phone transmitter generates at
    least two types of signals: a physical random access
    channel (PRACH) preamble, which is a scrambling code of
    4,096 chips; and a PRACH message part, which is a
    scrambling code of 38,400 chips. Both the PRACH pre-
    amble code and the PRACH message code are generated
    from the same theoretical long scrambling sequence
    named clong,1,n.
    InterDigital’s infringement theory at trial was that
    ZTE’s devices used the PRACH preamble code as the
    “successively transmitted signal” for detection by the base
    station, then used the PRACH message code as the sub-
    14       INTERDIGITAL COMMUNICATIONS    v. ZTE CORPORATION
    sequent transmission to the base station for identification
    or to let the base station know that a two-way communi-
    cation link is desired. ZTE argues here that, under that
    theory, its products do not meet two claim limitations.
    First, ZTE argues, the PRACH preamble and message are
    not “generated using a same code” (claim 1 of the ’966
    patent). Second, ZTE argues, it is not the case that the
    PRACH preamble is “generated using a portion of a code”
    and that the PRACH message is “generated using a
    remainder of the code” (claim 3 of the ’847 patent). We
    reject ZTE’s contention, concluding that the evidence
    permitted the jury reasonably to find otherwise.
    The 2006 technical specification for the 3GPP stand-
    ard, introduced as an exhibit at trial, explains that
    (1) there are 8,192 PRACH scrambling codes “defined”
    from the theoretical long scrambling sequence, clong,1,n,
    and (2) each of those “defined” 8,192 PRACH scrambling
    codes consists of 4,096 chips (preamble) plus 38,400 chips
    (message). J.A. 8971–72. Design documents from Qual-
    comm, which manufactures operative parts used in ZTE’s
    products, were also introduced at trial and say substan-
    tially the same thing. InterDigital’s infringement expert
    relied on those design documents to conclude that the
    PRACH preamble and message were generated using a
    section of clong,1,n: a series of 4,096 chips is generated,
    then a series of 38,400 chips “is simply continued from the
    end of the preamble.” J.A. 7269. Based on that evidence,
    a reasonable jury could find that the PRACH preamble
    and message are generated from “a same code” or from “a
    portion of a code” and from “a remainder of the code.”
    Contrary to ZTE’s argument, InterDigital’s invalidity
    expert did not give testimony inconsistent with that
    infringement finding.     InterDigital’s invalidity expert
    testified that one cannot randomly select a series of chips
    to serve as the preamble, then randomly select a series of
    chips to serve as the message, and ultimately claim that
    the preamble and message are part of a same code. He
    INTERDIGITAL COMMUNICATIONS   v. ZTE CORPORATION         15
    agreed with counsel that the two generated codes cannot
    be retrospectively combined but that the “same code has
    to be something which is somehow defined to be a se-
    quence.” J.A. 8339. His testimony is consistent with the
    Qualcomm documents, on which the infringement expert
    relied, as well as the 3GPP technical specification. The
    Qualcomm design documents explain that “the scram-
    bling code for the [P]RACH message corresponds to the
    same scrambling code that is used in the construction of
    the [P]RACH preamble.” J.A. 8617. Similarly, according
    to the 3GPP specification:
    The message part scrambling code has a one-to-
    one correspondence to the scrambling code used
    for the preamble part. For one PRACH, the same
    code number is used for both scrambling codes, i.e.
    if the PRACH preamble scrambling code used is
    St-pre,m, then the PRACH message part scrambling
    code is St-msg,m, where the number m is the same
    for both codes.”
    J.A. 8972. The PRACH preamble and the message are
    generated from a defined code—a portion of clong,1,n desig-
    nated by, for example, “the number m.” 
    Id.
    ZTE’s expert testified that the PRACH preamble and
    message are not generated from “a same code,” or from a
    “portion” and “remainder” of a code, because the preamble
    and message are different codes, of different lengths,
    generated at different times, and defined in different
    sections of the 3GPP standard. J.A. 8040–41. He (and
    ZTE) framed the issue as whether the mere fact that the
    preamble and message are generated by the same code
    generator was sufficient to find that the preamble and
    message are part of a same code. J.A. 8066–67. But the
    evidence, discussed above, shows that the preamble and
    message are not merely generated by the same code
    generator; they are generated one after the other from the
    same sequence, with a “one-to-one correspondence.” J.A.
    16       INTERDIGITAL COMMUNICATIONS   v. ZTE CORPORATION
    8972. The jury was entitled to reject the testimony of
    ZTE’s expert and rely on the testimony of InterDigital’s
    experts, the 3GPP technical specification, and the Qual-
    comm documents. We conclude that substantial evidence
    supports the verdict of infringement.
    III
    For the foregoing reasons, we affirm the district
    court’s judgment.
    AFFIRMED