Court Opinion

ID: 6339441
Source: CourtListenerOpinion
Date Created: 2022-05-11 14:00:38.156393+00
Date Added: 2024-06-11T15:49:11.929341
License: Public Domain

Case: 21-1998   Document: 45     Page: 1   Filed: 05/11/2022

   United States Court of Appeals
       for the Federal Circuit
                 ______________________

         SOUND VIEW INNOVATIONS, LLC,
                Plaintiff-Appellant

                            v.

                      HULU, LLC,
                   Defendant-Appellee
                 ______________________

                       2021-1998
                 ______________________

    Appeal from the United States District Court for the
 Central District of California in No. 2:17-cv-04146-JAK-
 PLA, Judge John A. Kronstadt.
                  ______________________

                 Decided: May 11, 2022
                 ______________________

    ALAN KELLMAN, Desmarais LLP, New York, NY, ar-
 gued for plaintiff-appellant.  Also represented by
 FREDERICK DING; PETER CURTIS MAGIC, San Francisco, CA.

     BRETT JOHNSTON WILLIAMSON, O'Melveny & Myers
 LLP, Newport Beach, CA, argued for defendant-appellee.
 Also represented by BRADLEY M. BERG, JOHN C. KAPPOS, BO
 MOON, CAMERON WILLIAM WESTIN; PATRICK NACK-
 LEHMAN, Menlo Park, CA.
                  ______________________

    Before PROST, MAYER, and TARANTO, Circuit Judges.
Case: 21-1998    Document: 45      Page: 2    Filed: 05/11/2022

 2                 SOUND VIEW INNOVATIONS, LLC   v. HULU, LLC

 TARANTO, Circuit Judge.
     Sound View Innovations, LLC owns now-expired U.S.
 Patent No. 6,708,213, titled “Method for Streaming Multi-
 media Information over Public Networks.” When Sound
 View brought the present case against Hulu, LLC, it al-
 leged infringement of six Sound View patents, but only
 claim 16 of the ’213 patent remains at issue. Sound View
 alleges that Hulu infringed claim 16 by its use of (third
 party) edge servers, which sit between a central Hulu con-
 tent server and the video-playing devices of end-user cus-
 tomers (clients). Most significantly for purposes of the
 infringement dispute currently before us, Sound View al-
 leges that, under Hulu’s direction, when an edge server re-
 ceives a client request for a video not already fully in the
 edge server’s possession, and obtains segments of the video
 seriatim from the content server (or another edge server),
 the edge server transmits to the Hulu client a segment it
 has obtained while concurrently retrieving a remaining
 segment.
      Claim 16 specifies a method, involving a content server
 and intermediate servers (helper servers), to use when a
 client requests a streaming multimedia (SM) object. One
 limitation requires “allocating a buffer” at a helper server
 “to cache” at least a portion of the SM object. The next lim-
 itation (the “downloading/retrieving limitation”) requires
 sending that portion to a requesting client while concur-
 rently retrieving a remaining portion of the SM object from
 the content server or another helper server. In the first
 ruling before us, the district court construed the download-
 ing/retrieving limitation not to cover a process in which the
 downloading occurs from one buffer in the helper server
 and the (concurrent) retrieving places what is retrieved in
 another buffer in that server. Rather, the court construed
 the limitation to require that the same buffer in the helper
 server—the one allocated in the preceding step—host both
 the portion sent to the client and a remaining portion re-
 trieved concurrently from the content server or other
Case: 21-1998    Document: 45      Page: 3    Filed: 05/11/2022

 SOUND VIEW INNOVATIONS, LLC   v. HULU, LLC                 3

 helper server. Sound View Innovations, LLC v. Hulu, LLC,
 No. LA CV17-04146, 2020 WL 10758103, at *5 (C.D. Cal.
 Apr. 13, 2020) (Claim Construction Opinion).
     With that claim construction in hand, Hulu sought
 summary judgment of non-infringement of claim 16, argu-
 ing that it was undisputed that, in the edge servers of its
 content delivery networks, no single buffer hosts both the
 video portion downloaded to the client and the retrieved
 additional portion. Sound View argued, in response, that
 there remained a factual dispute about whether “caches” in
 the edge servers met the concurrency limitation as con-
 strued. The district court held, however, that a “cache”
 could not be the “buffer” that its construction of the down-
 loading/retrieving limitation required, and on that basis, it
 granted summary judgment of non-infringement. Sound
 View Innovations, LLC v. Hulu, LLC, No. LA CV17-04146,
 2020 WL 6821317, at *6 (C.D. Cal. Oct. 20, 2020) (Sum-
 mary Judgment Opinion). A final judgment followed.
     Sound View appeals. It challenges the claim construc-
 tion and the summary judgment ruling. It also challenges
 two interlocutory rulings that excluded, under Federal
 Rule of Evidence 702, portions of Sound View’s expert tes-
 timony on reasonable-royalty damages. Sound View Inno-
 vations, LLC v. Hulu, LLC, No. LA CV17-04146, 2019 WL
 9047211, at *9–11 (C.D. Cal. Nov. 18, 2019) (Damages
 Opinion I); Order Re Defendant’s Supplemental Motion to
 Exclude Testimony of Mr. David Yurkerwich, Sound View
 Innovations, LLC v. Hulu, LLC, No. LA CV17-04146 (C.D.
 Cal. June 18, 2020), ECF No. 840 (Damages Opinion II).
     We affirm the district court’s construction of the down-
 loading/retrieving limitation. But we reject the district
 court’s determination that “buffer” cannot cover “a cache,”
 and we therefore vacate the district court’s grant of sum-
 mary judgment and remand for further proceedings. Be-
 cause the evidentiary rulings could matter on remand, we
 address those rulings—which we affirm.
Case: 21-1998     Document: 45      Page: 4     Filed: 05/11/2022

 4                  SOUND VIEW INNOVATIONS, LLC     v. HULU, LLC

                                I
                                A
      The ’213 patent describes and claims “methods which
 improve the caching of streaming multimedia data (e.g.,
 audio and video data) from a content provider over a net-
 work to a client’s computer.” ’213 patent, col. 1, lines 10–
 15. The methods use “helper servers (HS) . . . which oper-
 ate as caching and streaming agents.” Id., col. 2, lines 64–
 67. Delay in content delivery, server load, and network
 load can be reduced by using helper servers to respond to
 client requests. Id., col. 5, lines 46–50. In described em-
 bodiments, the invention “utilizes ring buffers in the
 memory of the HS.” Id., col. 5, lines 55–57. When a helper
 server receives a request for a streaming media (SM) ob-
 ject, and it does not already have the object, it requests the
 object from, e.g., the content server, which starts streaming
 it to the HS. Id., col. 6, lines 42–46. The HS “allocates a
 ring buffer in memory,” id., col. 6, line 54, which “is filled
 with data” from, e.g., the content server, id., col. 6, lines
 48–51. “The ring buffers represent a type of short term
 storage to service multiple requests for the same object
 which occur within a certain time range.” Id., col. 5, lines
 57–60. Referring to a ring buffer 57 of Figure 5A, the pa-
 tent states that “the ring buffer 57 operates as a type of
 short term cache which stores a portion of an SM object for
 a fixed time interval,” and, because it is emptied out by
 sending data to a client and replenished with more data,
 “[i]t is also convenient to view the ring buffer 57 as a sliding
 window in the sense that portions of an SM object are ini-
 tially cached in the ring buffer 57 and then deleted to store
 successive portions of the SM object.” Id., col. 7, lines 20–
 26.
     Claim 16 of the ’213 patent recites:
     16. A method of reducing latency in a network hav-
     ing a content server which hosts streaming media
     (SM) objects which comprise a plurality of time-
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 SOUND VIEW INNOVATIONS, LLC    v. HULU, LLC                 5

     ordered segments for distribution over said net-
     work through a plurality of helpers (HSs) to a plu-
     rality of clients, said method comprising:
         receiving a request for an SM object from
         one of said plurality of clients at one of said
         plurality of helper servers;
         allocating a buffer at one of said plurality
         of HSs to cache at least a portion of said re-
         quested SM object;
         downloading said portion of said requested
         SM object to said requesting client, while
         concurrently retrieving a remaining por-
         tion of said requested SM object from one of
         another HS and said content server; and
         adjusting a data transfer rate at said one of
         said plurality of HSs for transferring data
         from said one of said plurality of helper
         servers to said one of said plurality of cli-
         ents.
 Id., col. 14, lines 31–48.
                               B
      In June 2017, Sound View sued Hulu for infringement
 of claims of six patents, based on Hulu’s Streaming Video
 on Demand products, which use the edge servers of content
 delivery networks, including third parties Akamai and
 Level 3, to deliver content to clients. J.A. 203; J.A. 221–37.
 As to claim 16 of the ’213 patent, Sound View argued that
 Hulu directed or controlled the content delivery networks
 to allocate a local buffer at an edge server (the claimed
 “helper server”) to cache at least a portion of a Hulu video
 and to download that video portion to a client while concur-
 rently pre-fetching (i.e., retrieving) another portion of the
 video.
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 6                  SOUND VIEW INNOVATIONS, LLC   v. HULU, LLC

                               1
     The district court initially construed several claim
 terms, but the initial constructions are not disputed in this
 appeal. As the case proceeded, it became clear that the
 parties disputed the meaning of the downloading/retriev-
 ing limitation of claim 16. The district court’s resolution of
 the dispute is on appeal to us.
     Sound View argued that the limitation should be con-
 strued according to the ordinary meaning of its words,
 which do not include “buffer” and, more particularly, do not
 require that the concurrent sending out (downloading) and
 receiving (retrieving) involve the same buffer. Hulu ar-
 gued that the concurrent-function requirement must in-
 volve the same buffer, and it relied centrally (though not
 solely) on the prosecution history to support that construc-
 tion. During prosecution, the applicants added the entire
 downloading/retrieving limitation to original claim 16 to
 overcome a rejection over DeMoney (U.S. Patent No.
 6,438,630). The district court agreed with Hulu that the
 applicants’ statements accompanying the amendment dis-
 claimed the full scope of the downloading/retrieving limita-
 tion, and that the claim required the concurrent
 downloading from and filling of a single buffer. Claim Con-
 struction Opinion, 2020 WL 10758103, at *3–4. It thus con-
 strued     the   downloading/retrieving     limitation    as
 “downloading said portion of said requested SM object from
 said allocated buffer to said requesting client, while con-
 currently retrieving into the same buffer a remaining por-
 tion of said requested SM object from one of another HS
 and said content server.” Id. at *5 (emphases added).
 Sound View subsequently sought reconsideration of that
 decision, but the court denied the reconsideration motion.
 Sound View Innovations, LLC v. Hulu, LLC, No. LA CV17-
 04146, 2020 WL 5356698, at *5 (C.D. Cal. June 18, 2020).
     Hulu eventually sought summary judgment of non-in-
 fringement, arguing that it could not infringe claim 16
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 SOUND VIEW INNOVATIONS, LLC    v. HULU, LLC                  7

 because it was undisputed that the accused edge servers—
 the edge servers Sound View identified as the “helper serv-
 ers” for its infringement charge—do not download and re-
 trieve subsequent portions of the same SM object in the
 same buffer, so there could be no infringement in light of
 the court’s “same-buffer” claim-construction decision. J.A.
 3583–89. Sound View argued that there was a factual dis-
 pute as to whether certain caches in the accused edge serv-
 ers satisfied the requirements of claim 16. J.A. 3742–50.
 The district court agreed with Hulu and granted it sum-
 mary judgment of non-infringement of claim 16. Summary
 Judgment Opinion, 2020 WL 6821317, at *6. The court de-
 termined that the ’213 patent uses the terms “buffer” and
 “cache” to refer to distinct physical components and, there-
 fore, a cache could not satisfy the limitation of claim 16 re-
 quiring a buffer. Id. at *3–6. It determined that no further
 construction of “buffer” was necessary. Id. at *6 n.1.
                               2
     The district court issued two rulings related to dam-
 ages that are on appeal along with the claim-construction
 and summary-judgment rulings. Sound View proposed to
 have David Yurkerwich testify to what amount would con-
 stitute a reasonable royalty if infringement were found.
 Mr. Yurkerwich sought to show the value of the invention
 to a video-streaming provider based on the improved user
 experience if the invention were used, including fewer oc-
 casions of stalling of the video on the user’s device (“rebuff-
 ering events,” J.A. 2288) to await arrival of successive
 portions for display.
     Mr. Yurkerwich’s first damages opinion, J.A. 2819–25,
 relied in part on a study titled “Empirical Evaluation of
 HTTP Adaptive Streaming under Vehicular Mobility” by
 Yao et al. (the Yao study), which considered (through emu-
 lation) the experience of vehicle passengers in Sydney, Aus-
 tralia, watching streaming videos received on mobile
 devices over a Wireless Wide Area Network connection,
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 8                 SOUND VIEW INNOVATIONS, LLC   v. HULU, LLC

 J.A. 3175–78. According to Mr. Yurkerwich, the Yao study
 concluded that so-called “adaptive streaming” reduced the
 number of stalling occasions by 80%, and because the ’213
 patent teaches adaptive streaming (among other things),
 there would be an 80% decrease in stalling occasions if the
 patented technology were used. J.A. 2825. 1 Hulu moved
 to preclude Mr. Yurkerwich from presenting damages cal-
 culations that relied on the Yao study. The district court
 granted the motion, explaining that Mr. Yurkerwich did
 not present a sufficient basis to rely on the Yao study, as
 he did not account for the differences between the adaptive
 bit rate streaming that was the subject of the Yao study
 and Hulu’s alleged use of adaptive streaming, since many
 of Hulu’s U.S. customers use stationary devices and a WiFi
 or wired connection. Damages Opinion I, 2019 WL
 9047211, at *9–11.
     Mr. Yurkerwich subsequently submitted an amended
 report, J.A. 4446–4529, which removed references to the
 Yao study and instead relied on a press release by a com-
 pany called Conviva. But the amended report itself pre-
 sented an evidentiary problem. The Conviva press release

     1   The Abstract of Yao characterizes “adaptive
 streaming” in a way that corresponds, not to the download-
 ing/retrieving limitation (as construed to require same-
 buffer concurrency), but to the last limitation of claim 16,
 which calls for “adjusting a transfer rate.” See J.A. 3175
 (“Adaptive streaming is a promising technique for deliver-
 ing a high-quality video streaming experience. In this tech-
 nique, the streaming bit-rate is constantly adjusted in
 accordance with variations in the underlying network
 bandwidth conditions.”); see also Sound View’s Opening Br.
 at 17 (“[A]daptive bitrate streaming (ABR) [is] a key part
 of the infringing feature” (emphasis added)); id. at 53
 (“Hulu’s systems use ABR and are designed to change bi-
 trates based on available bandwidth.”).
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 SOUND VIEW INNOVATIONS, LLC    v. HULU, LLC                  9

 described a study of 22.6 billion video streams from viewers
 in 190 countries and asserted that users with an optimal
 streaming experience with startup time, stalling, and bit
 rate watched 250% more content. J.A. 3326–28. Mr. Yurk-
 erwich noted that a Hulu-commissioned study estimated
 that users of streaming systems with adaptive bit rate
 technology watched an even greater percentage of addi-
 tional content, J.A. 4524, but explained that he used the
 lower figure from Conviva in his calculations so that his
 estimate would be “conservative[],” id. When Hulu moved
 to exclude the amended report, the district court granted
 the motion because Mr. Yurkerwich never saw the under-
 lying study in the Conviva report and thus could not assess
 the methodology or even determine what streaming ser-
 vices were studied, and because he did not demonstrate
 that all of the identified benefits of the study were attribut-
 able to the patented invention or consider whether appor-
 tionment was warranted. Damages Opinion II, at 4–5. The
 district court struck Mr. Yurkerwich’s amended report and
 directed the parties to meet to confer about whether the
 aspects of Mr. Yurkerwich’s original report that did not
 rely on the Yao study could support a claim for damages.
 Damages Opinion II, at 5–6.
                               3
     After the parties stipulated to dismissal of the remain-
 ing claims and counterclaims, 2 the district court issued a
 final judgment of non-infringement of claim 16 of the ’213
 patent. J.A. 2. It also dismissed Hulu’s counterclaim for
 invalidity of claim 16 without prejudice. Id. Sound View

     2   The asserted claims regarding four of the patents,
 along with infringement and invalidity allegations con-
 cerning other claims of the ’213 patent, were dismissed at
 various points in the litigation. The court held invalid all
 asserted claims of another asserted patent, and Sound
 View has not appealed that decision.
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 10                SOUND VIEW INNOVATIONS, LLC   v. HULU, LLC

 timely appealed. We have jurisdiction over the district
 court’s final judgment under 28 U.S.C. § 1295(a)(1).
                              II
     We review de novo the claim-construction ruling con-
 cerning the downloading/retrieving limitation, as the rul-
 ing rests only on intrinsic evidence. Intel Corp. v.
 Qualcomm Inc., 21 F.4th 801, 808 (Fed. Cir. 2021). “We
 generally give words of a claim their ordinary meaning in
 the context of the claim and the whole patent document;
 the specification particularly, but also the prosecution his-
 tory, informs the determination of claim meaning in con-
 text, including by resolving ambiguities; and even if the
 meaning is plain on the face of the claim language, the pa-
 tentee can, by acting with sufficient clarity, disclaim such
 a plain meaning or prescribe a special definition.” World
 Class Technology Corp. v. Ormco Corp., 769 F.3d 1120,
 1123 (Fed. Cir. 2014) (citing Phillips v. AWH Corp., 415
 F.3d 1303, 1312–17 (Fed. Cir. 2005) (en banc), and Thorner
 v. Sony Computer Entertainment America LLC, 669 F.3d
 1362, 1365 (Fed. Cir. 2012)); see also Personalized Media
 Communications, LLC v. Apple Inc., 952 F.3d 1336, 1340
 (Fed. Cir. 2020) (“[A]n applicant’s amendment accompa-
 nied by explanatory remarks can define a claim term by
 demonstrating what the applicant meant by the amend-
 ment.”). Here, we conclude, as the district court did, that
 the prosecution history establishes that the download-
 ing/retrieving limitation must be construed to require the
 downloading and retrieving actions to involve the same
 buffer.
     Before discussing the prosecution history, we note that
 this is not a case in which the other intrinsic evidence—the
 claim language and specification—establish a truly plain
 meaning contrary to the meaning assertedly established by
 the prosecution history. The downloading/retrieving limi-
 tation, which does not expressly refer to “buffers,” contains
 no words affirmatively making clear that different buffers
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 SOUND VIEW INNOVATIONS, LLC    v. HULU, LLC                  11

 in the helper server may be used for the sending out to cli-
 ents of one portion of the SM object and the receiving of a
 retrieved remaining portion. In its opening phrase, “down-
 loading said portion of said requested SM object to said re-
 questing client,” ’213 patent, col. 14, lines 41–42 (emphasis
 added), the limitation refers indirectly to “a buffer” via the
 preceding limitation’s requirement of “allocating a
 buffer . . . to cache at least a portion” of the SM object, id.,
 col. 14, lines 39–40. In this claim, in which care is taken to
 use “a plurality of” when more than the singular is meant,
 “allocating a buffer” reasonably suggests allocating a single
 buffer. The next phrase, “while concurrently retrieving a
 remaining portion” of the same requested SM object, makes
 no mention of a separate buffer. And given the facially in-
 tegrated references to the two functions, the language is
 susceptible to being understood, in context, as implicitly
 calling for use of the same buffer for the storage of what is
 retrieved as the one used for the “downloading said por-
 tion” function. Proper claim construction “demands inter-
 pretation of the entire claim in context, not a single
 element in isolation.” Pause Technology, LLC v. TiVo, Inc.,
 419 F.3d 1326, 1331 (Fed. Cir. 2005) (citations omitted).
       The specification, of central importance to determining
 a proper claim construction, is not inconsistent with such a
 reading. As Sound View acknowledges, the specification
 nowhere says that the invention includes use of separate
 buffers for the concurrent downloading and retrieving
 functions, and it nowhere illustrates or describes such an
 embodiment, in which different buffers are involved in con-
 current downloading of one portion and retrieving of a re-
 maining portion of the same SM object in response to a
 given client’s request. See Sound View’s Opening Br. at 34
 n.5. The patent does, however, describe and illustrate an
 embodiment with only one buffer of the HS performing
 these simultaneous downloading (emptying) and retrieving
 (filling) functions. See ’213 patent, col. 8, lines 46–61; Fig.
 7B. In addition, when describing embodiments in which
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 12                 SOUND VIEW INNOVATIONS, LLC    v. HULU, LLC

 each HS has multiple buffers, i.e., “ring buffers in the
 memory,” id., col. 5, line 57, the specification indicates that
 “whenever a ring buffer is allocated” to respond to a client
 request, “as the ring buffer is filled, the data is simultane-
 ously streamed to the requesting client,” id., col. 7, lines
 55–58 (emphasis added).
     It is against this background that we consider the pros-
 ecution history. During prosecution, the examiner rejected
 original claim 16—which was identical to issued claim 16
 except that it lacked the downloading/retrieving limitation,
 J.A. 4395—as anticipated over DeMoney, J.A. 4415. To
 overcome the rejection, the applicants amended the claim
 to add the downloading/retrieving limitation to claim 16,
 J.A. 4406, and they distinguished DeMoney.
     The applicants explained that the added limitation,
 which “recite[d] additional features that the applicants
 consider as being inventive,” overcame the rejection based
 on DeMoney. J.A. 4410. The applicants first block quoted
 the Abstract of DeMoney and underlined a portion to high-
 light the distinction from the now-claimed invention:
      A system for scheduling storage accesses of multi-
      ple continuous media streams may include a plu-
      rality of media stream clients. Associated with
      each media stream client is one of a plurality of me-
      dia stream managers. Each media stream man-
      ager maintains a ring of buffers configured to
      buffer media stream data between its associated
      media stream client and one or more storage sys-
      tems. A different deadline queue may be associ-
      ated with each one of the storage systems. Each
      deadline queue may be configured to queue buffer
      requests from the media stream managers. Each
      buffer request may include a deadline by which the
      buffer request must be fulfilled by the correspond-
      ing storage system. Each media stream manager
      may be configured so that once one of its buffers is
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 SOUND VIEW INNOVATIONS, LLC   v. HULU, LLC                  13

     consumed by the associated media stream client,
     the media stream manager submits a buffer re-
     quest and deadline for that buffer to the appropri-
     ate deadline queue. Buffer requests may be
     ordered in each deadline queue from the earliest to
     latest deadline. Each media stream manager may
     be configured to provide a guaranteed maximum
     media stream rate to its associated media stream
     client.
 J.A. 4410–11 (underlining in applicants’ statements). The
 applicants then explained:
     By contrast, the applicants’ invention allocates a
     buffer . . . and downloads the portion of the SM ob-
     ject to the requesting client, while concurrently re-
     trieving a remaining portion of the requested SM
     object from another HS or a content server. That
     is, the applicants’ invention concurrently empties
     and fills the buffer, while the DeMoney reference
     teaches filling the buffer only after the buffer is
     empty.
 J.A. 4411 (underlining in applicants’ statements) (citing
 DeMoney, col. 12, lines 28–40). The cited portion of
 DeMoney, at column 12, lines 28–43, which is relevant to
 the concept of a “deadline queue” discussed in the abstract,
 explains: “As each buffer is consumed by the stream re-
 quester, a block request is issued along with a deadline
 time to fill the now consumed buffer[]”; the buffers “are ac-
 cessed one after another in a circular manner”; and “[t]he
 deadline time assures that each buffer is filled before it is
 needed by the stream requester.” Id., col. 12, lines 28–30,
 36–40. Finally, the applicants explained that support for
 the added limitation is found in the applicants’ specifica-
 tion, pointing to the portion of the specification that shows
 concurrent downloading and retrieval involving a single
 buffer, as noted above. J.A. 4412; see ’213 patent, col. 8,
 line 51, through col. 9, line 24.
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 14                 SOUND VIEW INNOVATIONS, LLC    v. HULU, LLC

      Based on the applicants’ statements, we agree with the
 district court that the applicants limited claim 16 to using
 the same buffer for the required concurrent downloading
 and retrieval of portions of a requested SM object. We may
 look at the prior art the applicants were discussing to de-
 termine what the applicants’ own words about prior art
 would mean to a relevant skilled artisan. See Speedtrack,
 Inc. v. Amazon.com, 998 F.3d 1373, 1378–80 (Fed. Cir.
 2021); see also Technology Properties Ltd. v. Huawei
 Techologies Co., 849 F.3d 1349, 1359 (Fed. Cir. 2017) (“The
 question is what a person of ordinary skill would under-
 stand the patentee to have disclaimed during prosecution,
 not what a person of ordinary skill would think the pa-
 tentee needed to disclaim during prosecution.”). Here, the
 portion of DeMoney cited by the applicants describes a pro-
 cess in which a single buffer of DeMoney downloads and
 retrieves portions of an SM object only serially, not concur-
 rently; once the buffer is “consumed” (emptied by down-
 loading to the client), it is placed in a queue with a deadline
 by which it must be filled. DeMoney, col. 12, lines 28–30.
 The passage describes the group of buffers as a whole per-
 forming these functions concurrently; one buffer in the ring
 downloads the object to the client, while the others in the
 ring are filled in accordance with their deadline queues.
 Id., col. 12, lines 36–40.
     The applicants in this case must be understood to have
 been distinguishing their invention (as newly narrowed by
 the added limitation) on the basis of the distinction be-
 tween serial and concurrent use of a single buffer. That
 distinction is communicated first by the applicants’ under-
 lining of the “once one of its buffers is consumed . . .” lan-
 guage of the DeMoney Abstract. J.A. 4411. It is then
 highlighted by the applicants’ assertion of the “contrast” of
 their invention with DeMoney: “That is, the applicants’ in-
 vention concurrently empties and fills the buffer, while the
 DeMoney reference teaches filling the buffer only after the
 buffer is empty,” citing column 12, lines 28–40 of DeMoney.
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 SOUND VIEW INNOVATIONS, LLC     v. HULU, LLC                   15

 J.A. 4411. And it is reinforced by the applicants’ pointing,
 for support of the added limitation, to a part of their speci-
 fication disclosing use of the same buffer for the concurrent
 processes. J.A. 4412.
     Sound View suggests that its view of separate-buffer
 concurrent actions (downloading and retrieving) would in
 fact have distinguished DeMoney because DeMoney does
 not disclose concurrent actions at all. But that is not the
 legal inquiry, which focuses, rather, on what the applicants
 said about the prior art. Sound View relies on a passage in
 DeMoney stating that the invention “allows future [stor-
 age] requests to be satisfied during lulls” of activity, id., col.
 11, lines 28–33, which suggests, according to Sound View,
 that the buffers in DeMoney, even considered as a whole,
 perform downloading and retrieving serially, not concur-
 rently. The applicants, however, did not cite that passage
 in overcoming the rejection, and in any event, the passage
 cannot establish what Sound View urges. Even if the pas-
 sage suggests that that DeMoney “allows” serial download-
 ing and retrieving in the ring of buffers, it does not exclude
 concurrent downloading and retrieving, and it does not ne-
 gate the disclosure of such concurrency in the passage that
 the applicants did cite.
     For those reasons, we reject Sound View’s challenge to
 the district court’s construction of the downloading/retriev-
 ing limitation, which we therefore affirm.
                                III
     After the district court adopted its “buffer”-requiring
 claim construction of the downloading/retrieving limita-
 tion, a construction we have now approved, it granted sum-
 mary judgment of non-infringement, concluding that
 accused-system components called “caches”—on which
 Sound View relied for its allegation of infringement under
 the court’s claim construction—could not be the required
 “buffers.” We review the district court’s grant of summary
 judgment here de novo. See Apple Inc. v. Wi-LAN Inc., 25
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 16                 SOUND VIEW INNOVATIONS, LLC      v. HULU, LLC

 F.4th 960, 969 (Fed. Cir. 2022) (citing Estate of Diaz v. City
 of Anaheim, 840 F.3d 592, 604 (9th Cir. 2016)). “Whether
 an accused device infringes requires a two-step analysis—
 the court first ‘determines the scope and meaning of the
 patent claims asserted, and then the properly construed
 claims are compared to the allegedly infringing device.’”
 CommScope Technologies LLC v. Dali Wireless Inc., 10
 F.4th 1289, 1295 (Fed. Cir. 2021) (citations omitted).
      The district court relied for its conclusion on the ’213
 patent’s references to its described “buffers” and “caches”
 as distinct physical components. Summary Judgment
 Opinion, 2020 WL 6821317, at *4, *6. The court noted that
 the ’213 patent describes buffers and caches in different lo-
 cations: The patent defines “cache” as “a region on the com-
 puter disk that holds a subset of a larger collection of data,”
 ’213 patent, col. 4, lines 7–8 (emphasis added); and alt-
 hough the patent does not define “buffer,” it describes “ring
 buffers” located “in the memory” of the HS, id., col. 5, lines
 55–60 (emphasis added). The court also cited other por-
 tions of the specification as distinguishing “buffers” and
 “caches.” See, e.g., id., col. 14, line 49, through col. 16, line
 4 (claim 17) (reciting both “managing available memory in
 the form of a buffer pool” and “means for recording data
 onto [a] cache”), id., col. 7, lines 55–67 (discussing sources
 for servicing client requests such as “the memory ring
 buffer,” and “cache on the disk”). The court then concluded
 that there could be no infringement because Sound View
 identified certain components in the accused edge servers
 labeled “caches” as meeting the “buffer” limitations (under
 its alternative infringement theory), Summary Judgment
 Opinion, 2020 WL 6821317, at *3, and “a cache” cannot sat-
 isfy the “buffer” limitations, id. at *6.
      To the extent that the district court performed the first
 step of an infringement analysis—claim construction—all
 it did for the term at issue, “buffer,” was to declare what it
 must exclude (a “cache”). The court did not adopt an af-
 firmative construction of what constitutes a “buffer” in this
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 SOUND VIEW INNOVATIONS, LLC    v. HULU, LLC                 17

 patent. But “‘[a]lthough there is no per se rule against neg-
 ative constructions,’ which in some cases can be enough to
 resolve the relevant dispute,” Intel, 21 F.4th at 811 (cita-
 tion omitted), the court’s construction here was inadequate
 for the second step of an infringement analysis—compari-
 son to the accused products or methods.
     The district court did not decide, and the record does
 not establish, that “cache” is a term of such uniform mean-
 ing in the art that its meaning in the ’213 patent must be
 relevantly identical to its meaning when used by those who
 labeled the pertinent components of the accused edge serv-
 ers. In the absence of such a uniformity-of-meaning deter-
 mination, the district court’s conclusion that the ’213
 patent distinguishes its buffers and caches is insufficient
 to support a determination that the accused-component
 “caches” are outside the “buffers” of the ’213 patent. What
 was needed was an affirmative construction of “buffer”—
 which could then be compared to the accused-component
 “caches” based on more than a mere name. The district
 court did not supply the needed construction.
     There is an additional reason a further, affirmative
 construction is needed. Even in the ’213 patent, the terms
 “buffer” and “cache” do not appear to be mutually exclusive,
 but instead seem to have at least some overlap in their cov-
 erage. The disputed claim describes “allocating a buffer . . .
 to cache” a portion of the SM object, ’213 patent, col. 14,
 lines 39–40 (emphasis added), and the specification ex-
 plains that “the ring buffer . . . operates as a type of short
 term cache” because it is capable of servicing multiple cli-
 ent requests within a certain time interval, id., col. 7, lines
 20–22 (emphasis added). This intrinsic evidence suggests
 the absence of mutual exclusivity in general usage of the
 terms.
     It appears that “buffer” should be given the ordinary
 meaning proposed by Sound View here and in the district
 court based on a dictionary definition: “temporary storage
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 18                 SOUND VIEW INNOVATIONS, LLC    v. HULU, LLC

 for data being sent or received.” See Sound View’s Opening
 Br. at 44; J.A. 3959, 3977. And Sound View set forth fac-
 tual evidence that the component of the accused edge serv-
 ers called a “cache” meets the requirements of a “buffer”
 under its own proposed construction. J.A. 3742–50. Hulu
 has not meaningfully advanced a contrary affirmative con-
 struction, and there is no definition stated in the ’213 pa-
 tent itself. But we do not decide the issue, instead leaving
 to the district court the determination whether to conduct
 further proceedings on what affirmative construction
 should be adopted.
     We note that the district court did not find it necessary
 to address a separate ground advanced by Hulu to support
 summary judgment of non-infringement. Hulu argued
 that it was undisputed that, even if the edge servers’ caches
 could satisfy the buffer limitations, claim 16 was still not
 met because, in the accused systems, those caches are not
 “allocated” to store at least a portion of the streaming me-
 dia object, as required by the “allocating a buffer” limita-
 tion of claim 16. J.A. 3997–98; see also Hulu’s Br. at 51.
 We will not address this assertion in the first instance.
    We vacate the summary judgment of non-infringement
 and remand the case.
                               IV
     Because we are remanding for further proceedings, we
 address the district court’s two rulings that excluded cer-
 tain damages evidence. We review a district court’s deci-
 sion to exclude expert testimony for an abuse of discretion.
 See General Electric Co. v. Joiner, 522 U.S. 136, 141 (1997)
 (“[A]buse of discretion is the proper standard of review of a
 district court’s evidentiary rulings.”); MLC Intellectual
 Property, LLC v. Micron Technology, Inc., 10 F.4th 1358,
 1367 (Fed. Cir. 2021); Messick v. Novartis Pharmaceuticals
 Corp., 747 F.3d 1193, 1196 (9th Cir. 2014). We find no
 abuse of discretion in the district court’s application in this
 case of the basic evidentiary standards requiring reliability
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 SOUND VIEW INNOVATIONS, LLC   v. HULU, LLC                 19

 and legal relevance of expert testimony—here offered on
 the issue of a reasonable royalty for the particular infringe-
 ment alleged. See Daubert v. Merrell Dow Pharmaceuti-
 cals, 509 U.S. 579, 589 (1993); see also, e.g., MLC
 Intellectual Property, 10 F.4th at 1373–75; VirnetX, Inc. v.
 Cisco Systems, Inc., 767 F.3d 1308, 1328 (Fed. Cir. 2014).
     Mr. Yurkerwich’s first damages opinion, as discussed,
 relied on a study of adaptive streaming used by mobile de-
 vices in vehicles connected to a wireless wide-area network
 in Sydney, Australia—the Yao study. Specifically, the
 study sought to emulate bandwidth variation on commut-
 ing routes in Sydney in order to assess how Hypertext
 Transfer Protocol (HTTP) adaptive streaming “perform[s]
 under a typical high-speed vehicular environment, wherein
 the wireless bandwidth varies significantly and rapidly.”
 J.A. 3175. Mr. Yurkerwich adopted the results of that
 study to conclude that “adaptive streaming” reduces occa-
 sions of stalling on users’ devices by 80%, thus showing a
 significant advantage of the patented technology over old
 technology. J.A. 2825. He then concluded that, because
 the ’213 patent calls for such “adaptive streaming,” Hulu’s
 use of adaptive streaming captured that significant ad-
 vantage, to be reflected in a royalty. Id.
     The district court reasonably determined that Mr.
 Yurkerwich did not account for substantial differences be-
 tween the circumstances studied by Yao and the circum-
 stances of Hulu’s accused streaming services. Specifically,
 Hulu’s services are used by many stationary viewers, on
 desktop computers or televisions, via WiFi or wired connec-
 tions with stable bandwidth, in the United States. Dam-
 ages Opinion I, 2019 WL 9047211, at *10. And the Yao
 study acknowledges that non-adaptive streaming “is usu-
 ally sufficient when the viewer is connected via a wired
 connection, which has high and fairly stable bandwidth ca-
 pacity,” J.A. 3175, supporting the court’s conclusion that
 Mr. Yurkerwich’s failure to account for the streaming be-
 havior of Hulu’s customers (including the proportion that
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 20                 SOUND VIEW INNOVATIONS, LLC   v. HULU, LLC

 use stationary devices with wired connections) rendered
 his opinion unreliable, Damages Opinion I, 2019 WL
 9047211, at *10. For those reasons, and because the testi-
 mony of Sound View’s technical expert regarding the Yao
 study does not fill the gaps in justifying use of the Yao
 study, the district court did not abuse its discretion in rec-
 ognizing that Mr. Yurkerwich’s wholesale adoption of the
 figures in the Yao study did not pass muster under the
 standards for admission of expert testimony. Id. at *9–11.
     Mr. Yurkerwich’s amended damages opinion relied on
 a 2013 Conviva press release describing a 2012 Viewer Ex-
 perience Report. The press release explains that the report
 measured over 22 billion video streams from viewers in 190
 countries. Mr. Yurkerwich adopted the press release’s ex-
 planation that users in the study watched 250% more con-
 tent when they had an “optimal experience” with startup
 times, buffering stalls, and bit rates; because those are pur-
 ported benefits of the claimed invention, he assumed that
 the study’s 250% increase in content should be credited to
 the claimed invention. J.A. 4523–24.
      The district court reasonably found a key reliability
 problem in the fact that Mr. Yurkerwich did not himself see
 the report underlying the Conviva press release and did not
 (and could not) adequately characterize the participants in
 the study (including what proportion were U.S. or non-U.S.
 companies), or the study’s methodology, in adopting the
 250% figure. Damages Opinion II, at 4. The district court
 recognized a decisive problem: “[T]he press release does not
 include a sufficient, in-depth discussion of the study so that
 it can be assessed, and then compared to the accused tech-
 nology.” Id. And those deficiencies, the district court rea-
 sonably determined, were not made immaterial by the
 simple fact that a Hulu internal document reflected an in-
 crease even higher than 250% in viewed content due to use
 of adaptive bit rate streaming. Damages Opinion II, at 5.
 Thus, the court did not abuse its discretion in excluding
 this testimony.
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 SOUND VIEW INNOVATIONS, LLC   v. HULU, LLC                 21

     Although the exclusion stands independently on the
 foregoing basis, the district court also reasonably con-
 cluded that Mr. Yurkerwich did not have an adequate basis
 for treating the results of the Conviva-reported study as
 sufficiently tied to the invention as claimed—or, therefore,
 for not undertaking apportionment that would exclude
 value reflected in the study (and derivatively in Hulu’s ser-
 vices) not attributable to the claimed invention. Damages
 Opinion II, at 4–5. In terms of claim 16, the invention to
 be valued is only the practicing of the entirety of claim 16,
 including all limitations. To tie the study results (or Hulu’s
 service value) sufficiently to claim 16 would require at least
 determining how much of the improvement in user experi-
 ence from use of adaptive streaming could still be achieved,
 and at what if any increased cost, without practicing the
 downloading/retrieving limitation of claim 16, with its re-
 quirement of concurrent emptying and filling of the same
 buffer (as opposed to using more than one buffer but still
 adjusting bit rates). The district court reasonably saw no
 adequate consideration of that conceptually central issue.
      Sound View has not justified a different conclusion
 based on its invocation of Alaska Rent-A-Car, Inc. v. Avis
 Budget Group, Inc., 738 F.3d 960, 969–70 (9th Cir. 2013).
 There, the Ninth Circuit concluded that the district court
 did not abuse its discretion in admitting certain expert tes-
 timony, whereas here Sound View seeks to reverse a dis-
 trict court’s decision to exclude. The substantive damages
 issues were different, too: the case involved lost profits for
 breach of contract, not, as here, a reasonable royalty for pa-
 tent infringement. Id. at 968. The Ninth Circuit held that
 the district court did not abuse its discretion in admitting
 testimony where the expert extrapolated market projec-
 tions involving similarly situated companies, “gave reasons
 for his use of [the] comparisons,” and used a reliable meth-
 odology to “calculate damages from the breach, as opposed
 to damages from competition.” Id. at 968–69. That ruling
 does not show that the district court in the present case
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 22                  SOUND VIEW INNOVATIONS, LLC    v. HULU, LLC

 abused its discretion in finding critical deficiencies of reli-
 ability and relevance on the different record here.
                                V
     For the foregoing reasons, we affirm the district court’s
 claim construction of the downloading/retrieving limitation
 and its exclusion of both the original and amended dam-
 ages testimony. But we vacate the entry of summary judg-
 ment of non-infringement and remand for further
 proceedings consistent with this opinion.
       The parties shall bear their own costs.
      AFFIRMED IN PART, VACATED IN PART, AND
                    REMANDED