Court Opinion

ID: 4659969
Source: CourtListenerOpinion
Date Created: 2021-02-12 16:00:40.483707+00
Date Added: 2024-06-11T08:02:02.950858
License: Public Domain

Case: 19-2196    Document: 70     Page: 1   Filed: 02/12/2021

   United States Court of Appeals
       for the Federal Circuit
                  ______________________

       SYNCHRONOSS TECHNOLOGIES, INC.,
               Plaintiff-Appellant

                             v.

                    DROPBOX, INC.,
                Defendant-Cross-Appellant

                   FUNAMBOL, INC.,
                        Defendant
                  ______________________

                   2019-2196, 2019-2199
                  ______________________

    Appeals from the United States District Court for the
 Northern District of California in No. 4:16-cv-00119-HSG,
 Judge Haywood S. Gilliam, Jr.
                  ______________________

                Decided: February 12, 2021
                 ______________________

    MARK LEE HOGGE, Dentons US LLP, Washington, DC,
 argued for plaintiff-appellant. Also represented by RAJESH
 CHARLES NORONHA, KIRK ROBERT RUTHENBERG; KEVIN R.
 GREENLEAF, Lovettsville, VA.

    ADAM HARBER, Williams & Connolly LLP, Washington,
 DC, argued for defendant-cross-appellant. Also repre-
 sented by DEBMALLO SHAYON GHOSH, DAVID M. KRINSKY,
 CHRISTOPHER MANDERNACH, THOMAS H.L. SELBY.
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 2            SYNCHRONOSS TECHNOLOGIES, INC   v. DROPBOX, INC.

                    ______________________

     Before PROST, Chief Judge, REYNA and TARANTO, Circuit
                            Judges.
 REYNA, Circuit Judge.
     Synchronoss Technologies, Inc. appeals the district
 court’s decisions that all asserted claims, drawn to technol-
 ogy for synchronizing data across multiple devices, are ei-
 ther invalid under 35 U.S.C. § 112, paragraph 2, or not
 infringed. Defendant Dropbox, Inc. cross-appeals asserting
 that all claims at issue are patent ineligible subject matter
 under § 101. For the reasons discussed below, we affirm
 the district court’s conclusions of invalidity under § 112
 and non-infringement and do not reach the question of pa-
 tent eligibility.
                         BACKGROUND
                    A. The Asserted Patents
     In its infringement suit, Synchronoss Technologies,
 Inc. (“Synchronoss”) alleged that Dropbox, Inc. (“Dropbox”)
 infringes U.S. Patent Nos. 6,671,757 (“’757 patent”),
 6,757,696 (“’696 patent”), and 7,587,446 (“’446 patent”) (col-
 lectively, “asserted patents”). 1 The ’757 patent describes a
 system for synchronizing data across multiple systems or
 devices connected via the Internet. The system generally
 involves one device or system that utilizes a first sync en-
 gine, a second device or system that utilizes a second sync
 engine, and a data store. See ’757 patent abstract
 (J.A. 6811). The first sync engine detects “difference infor-
 mation,” sends that information to the data store, and the

       1  During the litigation, Synchronoss asserted claims
 1, 8, 9, 14, 16, 21, 24, 26, and 28 of the ’757 patent, claims
 1, 2, 6–15, 18 and 19 of the ’446 patent, and claims 1, 3, 5,
 6, and 9–14 of the ’696 patent. See Appellant’s Br. 13.
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 data store in turn sends it to the second sync engine. See
 id. Using this system, “two devices need not be coupled to
 each other to perform a sync.” Id. at col. 3 ll. 30–31. The
 ’757 patent also explains that synchronization using the
 disclosed system “can occur at independent times using an
 intervening network based storage server to store changes
 to data for all the different devices in the system . . . .” Id.
 at col. 3 ll. 25–28. Claim 1 is illustrative and recites:
     1. A system for synchronizing data between a first
     system and a second system, comprising:
     a first sync engine on the first system interfacing
     with data on the first system to provide difference
     information in a difference transaction;
     a data store coupled to the network and in commu-
     nication with the first and second systems; and
     a second sync engine on the second system coupled
     to receive the difference information in the differ-
     ence transaction from the data store via the net-
     work, and interfacing with data on the second
     system to update said data on the second system
     with said difference information;
     wherein each said sync engine comprises a data in-
     terface, a copy of a previous state of said data, and
     a difference transaction generator.
 Id. at col. 46 l. 58–col. 47 l. 7. Remaining independent
 claims 16 and 24 are structured similarly to claim 1 but,
 among other differences, recite first and second “devices”
 rather than first and second “systems.” See id. at col. 48
 ll. 1–24, 51–64.
     The ’696 patent discloses a synchronization agent man-
 agement server connected to a plurality of synchronization
 agents via the Internet.        See ’696 patent abstract
 (J.A. 6861). The patent summarizes the claimed inven-
 tions as being drawn to a controller for a synchronization
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 system that maintains matching records and data for a
 user across multiple networked devices. See id. at col. 3
 ll. 20–23. It further explains that the disclosed inventions
 relate to a system for “transferring data between two de-
 vices[,] which require information to be shared between
 them.” Id. at col. 4 ll. 25–27. The synchronization agent
 management server “compris[es] a user login authentica-
 tor, a user data flow controller, and a unique user identifi-
 cation controller.” Id. at abstract. Claim 1 is illustrative
 and recites:
     1. A controller for a synchronization system, com-
     prising:
     a user identifier module;
     an authentication module identifying a user cou-
     pled to the synchronization system;
     a synchronization manager communicating with at
     least one interactive agent to control data migra-
     tion between a first network coupled device and a
     second network device;
     a transaction identifier module assigning a univer-
     sally unique identifier to each user of transaction
     objects in said data store; and
     a current table of universally unique identifier val-
     ues and versioning information, generated by ver-
     sioning modules on said devices associating a
     transaction identifier with each transaction object,
     providing a root structure for understanding the
     data package files.
 J.A. 6901. Remaining asserted independent claims 9 and
 16 cover similar subject matter, except that claim 9 recites
 a “user authentication module” instead of an “authentica-
 tion module.” Id. at col. 45 ll. 49–56; J.A. 6899. Also, claim
 16 recites a “user login authenticator” rather than claim 1’s
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 “authentication module,” and it additionally recites a “user
 data flow controller.” Id. at col. 46 ll. 13–20; J.A. 6899.
      The ’446 patent describes a “method for transferring
 media data to a network coupled apparatus.” ’446 patent
 abstract (J.A. 6902). The patent summarizes the disclosed
 inventions as methods that involve (i) maintaining a “mu-
 sic store” in a user’s dedicated personal information space
 and (ii) transferring some of the data from that personal
 information space to the user’s Internet-coupled device
 upon request. See id. at col. 3 ll. 45–51. Claim 1 is illus-
 trative and recites:
    1. A method of transferring media data to a net-
    work coupled apparatus, comprising:
    (a) maintaining a personal information space iden-
    tified with a user including media data comprising
    a directory of digital media files, the personal infor-
    mation space being coupled to a server and a net-
    work;
    (b) generating a first version of the media data in
    the personal information space;
    (c) generating a digital media file, in response to an
    input from the user, comprising a second version of
    the media data in a same format as the first version
    in the personal information space, the second ver-
    sion including an update not included in the first
    version;
    (d) obtaining difference information comprising dif-
    ferences between the first version of the media data
    and the second version of the media data; and
    (e) transferring a digital media file over the net-
    work containing the difference information from
    the personal information space to the network cou-
    pled apparatus in response to a sync request made
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     from a web browser at the network-coupled appa-
     ratus by the user.
 Id. at col. 13 l. 47–col. 14 l. 2. Claim 11, the other inde-
 pendent claim, recites a system for carrying out the method
 of claim 1 comprising a “personal information store,” a
 “processing device,” and a “server” for transferring digital
 media from the “personal information store” to a “network
 coupled apparatus.” See id. at col. 14 ll. 35–57.
                    B. Procedural History
     Synchronoss filed a complaint on March 27, 2015, al-
 leging that Dropbox infringed the ’757, ’696, and ’446 pa-
 tents. On February 5, 2016, Dropbox filed a motion to
 dismiss the complaint on the grounds that all three as-
 serted patents were patent ineligible subject matter under
 § 101. J.A. 654–83. On December 22, 2016, the district
 court denied Dropbox’s motion, concluding that “the chal-
 lenged claims, viewed as an ordered combination, impose
 specific limitations sufficient under Enfish and McRO to
 survive at the motion to dismiss stage.” J.A. 55. It further
 concluded that the asserted claims, as described in the pa-
 tents, are “directed to improving the manner in which com-
 puters synchronize data between devices connected to a
 network,” resulting in an increase in speed and a reduction
 in required bandwidth and storage space. See id. Shortly
 thereafter, in February 2017, the district court referred the
 case to a magistrate judge for discovery purposes.
      The following month, in March 2017, the district court
 set a claim construction schedule. Dropbox and its tech-
 nical expert, Dr. Freedman, contended in its briefing that
 certain terms that appear across all the ’696 patent’s as-
 serted claims are indefinite because they constitute func-
 tional limitations that invoke 35 U.S.C. § 112, paragraph
 6, but do not correspond to adequate structure in the spec-
 ification. These six terms include: (i) “user identifier mod-
 ule” (in all claims); (ii) “authentication module identifying
 a user coupled to the synchronization system” (in claim 1);
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 (iii) “user authenticator module” (in claim 9); (iv) “user
 login authenticator” (in claim 16); (v) “user data flow con-
 troller” (in claim 16); and (vi) “transaction identifier mod-
 ule” (in all claims). J.A. 25–32, 37–39, 6898–901.
     Specifically, Dr. Freedman opined that the terms “mod-
 ule,” “authenticator,” and “controller”—one of which ap-
 pears in all of the six terms—would be understood by
 persons of ordinary skill in the art as functional terms that
 do not impart any particular structure. J.A. 26–28. He
 further opined that the six terms’ prefixes to those words—
 for example, “user login authenticator”—similarly would
 be understood as functional language devoid of particular
 structure. J.A. 27–28. He also testified that a person of
 ordinary skill in the art would understand “dozens of dis-
 crete ways” to implement the six functional claim terms,
 and that the specification failed to describe any specific
 structure for carrying out the respective functions. See
 J.A. 27–28, 38, 1884, 2187–88, 2190, 2193–94, 2203–04.
 Synchronoss offered no contrary expert testimony but tried
 to repurpose Dr. Freedman’s list of known ways to perform
 the claimed functions as evidence that a person of ordinary
 skill in the art understood the terms as having structure.
 J.A. 28, 38, 1671–72, 1681–82. Synchronoss also cited dic-
 tionaries and previous district court decisions to argue that
 the terms were understood in the field to have structure.
 See J.A. 28, 1671–75. The district court rejected Syn-
 chronoss’s arguments, credited Dr. Freedman’s testimony,
 and concluded that all claims in the ’696 patent are invalid
 as indefinite. J.A. 25–32.
     The court also construed hardware-related terms that
 appear in all asserted claims, namely “system,” “device,”
 and “apparatus.” J.A. 24. Synchronoss proposed the fol-
 lowing construction, which is the language used by the as-
 serted patents to define the term, “device”:
     a collection of elements or components organized
     for a common purpose, and may include hardware
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 8           SYNCHRONOSS TECHNOLOGIES, INC     v. DROPBOX, INC.

     components of a computer system, personal infor-
     mation devices, hand-held computers, notebooks,
     or any combination of hardware which may include
     a processor and memory which is adapted to re-
     ceive or provide information to another device; or
     any software containing such information residing
     on a single collection of hardware or on different
     collections of hardware.
 J.A. 24; see also ’757 patent col. 5 ll. 13–23; ’696 patent
 col. 4 ll. 27–36; ’446 patent col. 1 ll. 8–11 (incorporating by
 reference the ’757 patent)).
     Synchronoss also argued that Dropbox’s proposed con-
 struction—which included a list of computing devices—was
 “not incorrect, but incomplete to the extent that it limits
 the definition to hardware devices.” J.A. 24. Dropbox re-
 sponded that the term “device” could not properly be con-
 strued to exclude hardware. J.A. 1877 (“[T]o the extent the
 definition of ‘device’ purports to cover mere software in the
 absence of any hardware, it is inconsistent with how ‘de-
 vice’ is used in the claims.”). Dropbox pointed to the fact
 that certain claims required a device to be “coupled” to a
 network, and that software in the absence of hardware is
 not capable of such coupling. Id. Notably, at the hearing,
 Synchronoss agreed with Dropbox that “device” could not
 mean software “completely detached” from hardware.
 J.A. 2481–82. The district court adopted Synchronoss’s
 construction because of its express support in the asserted
 patents. J.A. 25. But it also agreed with Dropbox that the
 claims could not cover software in the absence of hard-
 ware. 2

     2   See J.A. 25 (“Defendants’ third argument concern-
 ing stand-alone software does not apply here, as the Court
 understands the ’757 Patent’s use of the term ‘software’ to
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     In May 2019, following the district court’s claim con-
 struction order invalidating the ’696 patent’s asserted
 claims as indefinite, Dropbox moved for summary judg-
 ment with respect to the remaining ’757 and ’446 patents.
 Dropbox first argued that all asserted claims of the ’446
 patent were indefinite because they contain an impossibil-
 ity. Specifically, the claims require “generating a [single]
 digital media file” that itself “compris[es] a directory of dig-
 ital media files.”        J.A. 11.    Synchronoss’s expert,
 Mr. Alpaugh, conceded that “a digital media file cannot
 contain a directory of digital media files.” J.A. 12, 4985.
 Mr. Alpaugh had further testified that “comprising was ad-
 mittedly the wrong choice of words and perhaps the better
 word here would have been resulting in a second version or
 some other choice.” J.A. 12, 4985. Synchronoss’s corporate
 designee similarly testified that “if someone were to sug-
 gest that ‘media data’ always means ‘directory of digital
 media files[,]’ . . . then Clause C would not make sense.”
 J.A. 12, 6490. Synchronoss responded that a person of or-
 dinary skill in the art “would have been reasonably certain
 that the asserted ’446 patent claims require a digital media
 that is a part of a directory because a file cannot contain a
 directory.” J.A. 6109. The district court rejected Syn-
 chronoss’s argument as an improper attempt to redraft the
 claims and thus granted summary judgment in favor of
 Dropbox that all asserted claims of the ’446 patent are in-
 definite. J.A. 13.
     Dropbox also sought summary judgment that the as-
 serted claims of the ’757 and ’446 patents are not infringed
 because the asserted claims, as construed, all required
 hardware, but Dropbox’s accused software could not meet
 that requirement. J.A. 6268–72. Synchronoss responded
 that the “[t]he participle phrase ‘residing on hardware’

 reference software in combination with a hardware compo-
 nent or element.”) (citing J.A. 1877, 2482).
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 describes location; it is not an independent requirement of
 the claims.” J.A. 7, 6098. In other words, according to Syn-
 chronoss, the asserted claims only cover “the ‘software’ re-
 siding on the hardware, but not the hardware itself.”
 J.A. 7, 6098. Under this interpretation of the claims, Syn-
 chronoss argued, Dropbox’s software infringed.
      The district court rejected Synchronoss’s argument and
 granted summary judgment of non-infringement, noting
 that Synchronoss agreed at the claim construction hearing
 that the asserted claims did not encompass “software com-
 pletely detached from hardware.” J.A. 7–8, 25, 2482. The
 district court explained that, in its claim construction or-
 der, it had “unambiguously held that ‘[first/second] system’
 did not cover software alone.” J.A. 7; see also J.A. 25 (“[T]he
 Court understands that the ’757 Patent’s use of the term
 ‘software’ to reference software in combination with a hard-
 ware component of element.”). The district court further
 rejected Synchronoss’s theory, based on Uniloc USA, Inc.
 v. Microsoft Corp., 632 F.3d 1292 (Fed. Cir. 2011), that the
 claims required software “in residence” on hardware but
 not the hardware itself. J.A. 8. Because all asserted claims
 of the ’757 and ’446 patents required hardware and Syn-
 chronoss did not accuse any Dropbox hardware of infring-
 ing, the court granted summary judgment of non-
 infringement as to the ’757 and ’446 patents. Synchronoss
 appeals the district court’s claim construction and sum-
 mary judgment decisions. Dropbox cross-appeals the dis-
 trict court’s denial of Dropbox’s motion to dismiss. We have
 jurisdiction under 28 U.S.C. § 1295(a)(1).
                          DISCUSSION
     We review the grant of summary judgment under the
 law of the regional circuit in which the district court sits,
 here, the Ninth Circuit. Classen Immunotherapies, Inc. v.
 Elan Pharm., Inc., 786 F.3d 892, 896 (Fed. Cir. 2015). Ap-
 plying Ninth Circuit law, we review the district court’s
 grant of summary judgment de novo. Amgen Inc. v. Sandoz
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 Inc., 923 F.3d 1023, 1027 (Fed. Cir. 2019). We review a
 district court’s claim constructions, including determina-
 tions of indefiniteness, de novo, but we review subsidiary
 factual findings based on extrinsic evidence for clear error.
 MasterMine Software, Inc. v. Microsoft Corp., 874
 F.3d 1307, 1310 (Fed. Cir. 2017). Patent eligibility under
 § 101 is ultimately a question of law, reviewable de novo,
 which may contain underlying issues of fact. Berkheimer
 v. HP Inc., 881 F.3d 1360, 1365 (Fed. Cir. 2018).
                       A. Jurisdiction
     We first address a threshold question of jurisdiction.
 Absent extraordinary circumstances, for a district court
 judgment to be appealable to this court under 28 U.S.C.
 § 1295(a)(1), the judgment must resolve all claims and
 counterclaims or make an express determination under
 Rule 54(b) of the Federal Rules of Civil Procedure that
 there is no just reason for delay. SafeTCare Mfg., Inc. v.
 Tele-Made, Inc., 497 F.3d 1262, 1267 (Fed. Cir. 2007); see
 also Int’l Elec. Tech. Corp. v. Hughes Aircraft Co., 476
 F.3d 1329, 1330 (Fed. Cir. 2007) (concluding no final judg-
 ment, and thus a lack of jurisdiction, where the defendants’
 counterclaims were never dismissed and thus remained ex-
 tant).
      In its order granting summary judgment of non-in-
 fringement on the ’757 patent, the district court denied as
 moot Synchronoss’s motion for summary judgment of va-
 lidity of the ’757 patent. A finding of non-infringement,
 however, does not by itself moot a request for declaratory
 judgment of invalidity. See Cardinal Chem. Co. v. Morton
 Int’l, Inc., 508 U.S. 83, 98 (1993). Therefore, Dropbox’s in-
 validity counterclaims survived the judgment of non-in-
 fringement, and the district court’s purported “final
 judgment” based on its summary judgment decision did not
 constitute a final decision under 28 U.S.C. § 1295(a)(1).
     In Amgen Inc. v. Amneal Pharmaceuticals LLC, 945
 F.3d 1368, 1374 (Fed. Cir. 2020), we held that a party can
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 12          SYNCHRONOSS TECHNOLOGIES, INC       v. DROPBOX, INC.

 “cure” a jurisdictional defect stemming from its unresolved
 invalidity counterclaim if it agrees to “‘give up’” the claim
 regardless of the outcome of the appeal. We held that such
 a representation, even made at oral argument, effectively
 “nullifie[s]” the outstanding issues, rendering the court’s
 judgment as to infringement “final” for purposes of our ju-
 risdiction. Id. During oral argument, Dropbox agreed to
 give up its invalidity counterclaims with respect to the ’757
 patent.      Oral Arg. at 6:27–13:08, http://oralargu-
 ments.cafc.uscourts.gov/default.aspx?fl=19-2196.mp3.
 Based on Dropbox’s representation as to its counterclaims,
 we deem the district court’s judgment final and we assert
 jurisdiction under § 1295(a)(1).
                        B. Indefiniteness
     Synchronoss challenges the district court’s conclusions
 that the asserted claims of the ’446 and ’696 patents are
 indefinite under 35 U.S.C. § 112. Section 112, paragraph
 2, provides that “[t]he specification shall conclude with one
 or more claims particularly pointing out and distinctly
 claiming the subject matter which the applicant regards as
 his invention.” 35 U.S.C. § 112. A patent claim is indefi-
 nite if it fails to provide a person of ordinary skill in the art
 reasonable certainty regarding the scope of the claimed in-
 vention. Nautilus, Inc. v. Biosig Instruments, Inc., 572 U.S.
 898, 901 (2014); Biosig Instruments, Inc. v. Nautilus, Inc.,
 783 F.3d 1374, 1380–81 (Fed. Cir. 2015).
                       1. The ’446 Patent
      The district court granted summary judgment that the
 asserted claims of the ’446 patent are invalid under § 112,
 paragraph 2, on the ground they contain an impossibility.
 The evidence supports that conclusion. Specifically, the
 ’446 patent’s asserted claims require “generating a [single]
 digital media file” that itself “compris[es] a directory of dig-
 ital media files.” J.A. 11. Synchronoss’s expert, however,
 testified that “a digital media file cannot contain a direc-
 tory of digital media files,” J.A. 12, 4985, and Synchronoss’s
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 corporate designee testified the claims would “not make
 sense” if “media data” was understood to mean “directory
 of media files,” J.A. 12, 6490.
     Synchronoss does not dispute that the claims contain
 an impossibility. It contends that a person of ordinary skill
 in the art would read the specification and reasonably un-
 derstand that the inventions “mean that, in response to in-
 put from a user, a digital media file is generated as a
 second, updated version of the media data in the same for-
 mat as the first version of the media data.” Appellant’s
 Br. 39. We are not persuaded.
      In Allen Engineering Corp. v. Bartell Industries, Inc.,
 we explained that where a person of ordinary skill in the
 art would understand based on the specification that the
 claims do not set forth what the inventor regards as his in-
 vention, the claims are invalid under § 112, paragraph 2.
 299 F.3d 1336, 1349 (Fed. Cir. 2002) (rejecting the argu-
 ment that “perpendicular” would be understood as “paral-
 lel” in light of the specification’s teachings). In Trustees of
 Columbia University in City of New York v. Symantec
 Corp., we held the claims indefinite because they nonsen-
 sically “describe[d] the step of extracting machine code in-
 structions from something that does not have machine code
 instructions.” 811 F.3d 1359, 1367 (Fed. Cir. 2016). Here,
 the asserted claims of the ’446 patent are nonsensical and
 require an impossibility—that the digital media file con-
 tain a directory of digital media files. Adopting Syn-
 chronoss’s proposal would require rewriting the claims, but
 “it is not our function to rewrite claims to preserve their
 validity.” Allen, 299 F.3d at 1349. We therefore hold that
 the claims are indefinite as a matter of law under § 112,
 paragraph 2.
                      2. The ’696 Patent
     The district court concluded in its claim construction
 order that all asserted claims of the ’696 patent are indefi-
 nite because six claim terms that appear across all asserted
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 14          SYNCHRONOSS TECHNOLOGIES, INC     v. DROPBOX, INC.

 claims did not correspond to adequate structure disclosed
 in the specification.
     The threshold inquiry is whether the claims at issue
 invoke § 112, paragraph 6. The standard is whether a per-
 son of ordinary skill in the art would understand that the
 claim terms recite a function but not sufficient structure
 for performing the function. See Williamson v. Citrix
 Online, LLC, 792 F.3d 1339, 1349 (Fed. Cir. 2015) (citing
 Greenberg v. Ethicon Endo-Surgery, Inc., 91 F.3d 1580,
 1583 (Fed. Cir. 1996)). Even if a claim term lacks the word
 “means,” § 112, paragraph 6 is invoked if the challenger
 shows that the claim term fails to recite sufficiently defi-
 nite structure or recites a function without sufficient struc-
 ture for performing that function. Williamson, 792 F.3d
 at 1349 (citing Watts v. XL Sys., Inc., 232 F.3d 877, 880
 (Fed. Cir. 2000)).
     If a claim term invokes § 112, paragraph 6, we apply a
 two-step process for construing the term. The first step is
 to identify the claimed function. Williamson, 792 F.3d
 at 1351. The second step is to determine whether sufficient
 structure is disclosed in the specification that corresponds
 to the claimed function. Id. If the specification fails to dis-
 close adequate corresponding structure, the claim is indef-
 inite. Id. at 1351–52.
     Against that legal backdrop, we turn to the claim terms
 at issue. The term “user identifier module” appears in all
 asserted claims of the ’696 patent. According to Syn-
 chronoss, the function of this claim term is “identifying a
 user.” Appellant’s Br. 52. Synchronoss argues that “[t]he
 algorithm of the top half of Fig. 17” and the text at col-
 umn 32, lines 6 to 34, together describe structure sufficient
 to achieve the function of identifying a user. Id. at 53. We
 disagree.
     The cited portion of Figure 17 depicts alternative steps
 labeled “forgot password,” “sign up,” “provide specific infor-
 mation,” and “login.” ’696 patent at Fig. 17. It also depicts
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 a downstream step labeled “confirm account.” Id. The cor-
 responding text cited by Synchronoss, however, does not
 detail what a user identifier module consists of or how it
 operates. See id. col. 32 ll. 6–34. Dropbox’s expert,
 Dr. Freedman, identified “many ways in which a system
 could perform user identification, each with its own dis-
 tinct structure.” J.A. 2187–88. Synchronoss offered no con-
 trary expert testimony, but rather relied on
 Dr. Freedman’s list of “nearly 20 different structures” as
 evidence that a user identifier module would be understood
 by a person of ordinary skill in the art as corresponding to
 structure. J.A. 28. In doing so, Synchronoss illustrated
 that the claim term “user identifier module” does what the
 definiteness requirement prohibits. It is not enough that a
 means-plus-function claim term correspond to every
 known way of achieving the claimed function; instead, the
 term must correspond to “adequate” structure in the spec-
 ification that a person of ordinary skill in the art would be
 able to recognize and associate with the corresponding
 function in the claim. See Williamson, 792 F.3d at 1352.
 Because the term “user identifier module” fails in this re-
 gard, we hold that the term is indefinite and, thus, the as-
 serted claims of the ’696 patent are invalid. As the term
 appears in all asserted claims, we do not address the re-
 maining five terms in the asserted claims of the ’696 pa-
 tent, which the district court also deemed indefinite.
                       C. Infringement
     Synchronoss appeals the district court’s grant of sum-
 mary judgment of non-infringement on all asserted claims
 of the ’757 patent. 3 Synchronoss argues that the district

     3   Synchronoss also challenges the district court’s
 conclusion that the ’446 patent’s asserted claims are not
 infringed. Given our conclusion above that those claims
 are indefinite, we address the infringement issue only as to
 the ’757 patent.
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 16         SYNCHRONOSS TECHNOLOGIES, INC     v. DROPBOX, INC.

 court erred in concluding that the asserted claims require
 hardware. Synchronoss specifically contends that the as-
 serted claims—as construed by Synchronoss—recite hard-
 ware not as a claim limitation, but merely as a reference to
 the “location for the software,” Appellant’s Br. 26, or “the
 environment in which software operates,” id. at 24.
     The district court determined that the language, “soft-
 ware . . . residing on . . . hardware,” proposed by Syn-
 chronoss as a construction for the terms “device,” “system,”
 and “apparatus,” J.A. 22, limits the asserted claims’ scope
 and thus requires infringing technology to possess hard-
 ware. See J.A. 7–8. In reaching this conclusion, the court
 emphasized Synchronoss’s concession that the asserted
 claims, as construed, could not cover software absent hard-
 ware. See J.A. 7–8.
      Synchronoss argues that its agreement that the claims
 cannot cover “software completely detached from hard-
 ware” was not a concession that the claims require hard-
 ware. Appellant’s Br. 29. Instead, Synchronoss argues
 that the district court “misinterpreted Synchronoss’ coun-
 sel’s assent to that statement” and that Synchronoss’s po-
 sition has consistently been that the term “hardware” in its
 proposed construction refers in a non-limiting sense to the
 “hardware environment” in which “the software is always
 expected to work.” Id. We disagree.
      We conclude that the “hardware” term limits the scope
 of the asserted claims of the ’757 patent. Synchronoss itself
 proposed the construction including the “hardware” term
 on the basis that the asserted patents used that language
 to define the term “device.” Synchronoss also agreed with
 the district court that “no one’s arguing that a device could
 be software completely detached from hardware.”
 J.A. 2481–82. The conclusion that the “hardware” term
 limits the claim scope is thus consistent with both Syn-
 chronoss’s own assertions and the record evidence.
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 SYNCHRONOSS TECHNOLOGIES, INC    v. DROPBOX, INC.          17

      The evidence shows that Dropbox provides its custom-
 ers with software for download but no corresponding hard-
 ware. See, e.g., J.A. 6358 (Synchronoss’s expert, Mr.
 Alpaugh, testifying that “I’m not aware of them selling any
 hardware. . . . The hardware is not part of my opinion.”);
 see also Appellant’s Br. 36 (“[T]he claims at issue in this
 case are satisfied by the software that Dropbox makes, of-
 fers for sale and sells.” (emphasis added)). Because Drop-
 box does not provide its customers with any hardware in
 conjunction with its accused software, Dropbox does not
 make, sell, or offer for sale the complete invention. See Ro-
 tec Indus., Inc. v. Mitsubishi Corp., 215 F.3d 1246, 1252 n.2
 (Fed. Cir. 2000) (“[O]ne may not be held liable under
 § 271(a) for ‘making’ or ‘selling’ less than a complete inven-
 tion.”).
      Nor does Dropbox directly infringe by “using” the en-
 tire claimed system under § 271(a). Direct infringement by
 “use” of a claimed system requires use of each and every
 element of the system. Centillion Data Sys., LLC v. Qwest
 Commc’ns Int’l, Inc., 631 F.3d 1279, 1284 (Fed. Cir. 2011).
 “[T]o ‘use’ a system for purposes of infringement, a party
 must put the invention into service, i.e., control the system
 as a whole and obtain benefit from it.” Id. (citing NTP, Inc.
 v. Research In Motion, Ltd., 418 F.3d 1282, 1317 (Fed.
 Cir. 2005)).
     In Centillion, the claims recited a system comprising
 back-end computing means to carry out certain functions,
 as well as end users’ “personal computer data processing
 means.” 631 F.3d at 1282. We reasoned that, “[w]hile
 Qwest may make the back-end processing elements, it
 never ‘uses’ the entire claimed system because it never puts
 into service the personal computer data processing means.”
 Id. at 1286. “Supplying the software for the customer to
 use,” we explained, “is not the same as using the system.”
 Id.
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 18         SYNCHRONOSS TECHNOLOGIES, INC     v. DROPBOX, INC.

      Synchronoss argues that the district court misinter-
 preted Centillion, Appellant’s Br. 33, and that Centillion
 does not apply given its factual differences to this case, Ap-
 pellant’s Reply Br. 10. We disagree. Although Centillion
 involves distinct facts, the legal standard articulated in
 Centillion applies to whether Dropbox directly infringes by
 “using” Synchronoss’s claimed system. See Centillion, 631
 F.3d at 1284. Synchronoss fails to identify how the district
 court misstated or misapplied that standard. In the ab-
 sence of a genuine factual dispute as to Dropbox’s control
 of, and benefit from, the claimed system, we find no error
 in the district court’s conclusion that Dropbox does not di-
 rectly infringe by “using” the claimed system under
 § 271(a).
     For these reasons, we affirm the district court’s grant
 of summary judgment of non-infringement with respect to
 the asserted claims in the ’757 patent.
                       D. Cross-Appeal
     Because we affirm the district court’s judgment of in-
 validity of the asserted claims of the ’696 and ’446 patents
 under § 112, paragraph 2, we need not reach the question
 of whether those claims are patent eligible under 35 U.S.C.
 § 101. Nor do we reach that question with respect to the
 asserted claims of the ’757 patent, given Dropbox’s agree-
 ment at oral argument to waive its invalidity counter-
 claims with respect to the ’757 patent. See, e.g., Amgen,
 945 F.3d at 1374.
                         CONCLUSION
     We have considered the parties’ remaining arguments
 and find them unpersuasive. Accordingly, we affirm the
 district court’s judgments of invalidity under § 112, para-
 graph 2, with respect to the ’446 and ’696 patents and non-
 infringement with respect to the ’757 patent.
                         AFFIRMED
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 SYNCHRONOSS TECHNOLOGIES, INC   v. DROPBOX, INC.        19

                          COSTS
     No costs.