Paper No. 95
`Filed: December 6, 2019
`
`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`
`––––––––––––––––––
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`
`––––––––––––––––––
`
`THE MANGROVE PARTNERS MASTER FUND, LTD. and APPLE INC.,
`Petitioners,
`
`v.
`
`VIRNETX INC.,
`Patent Owner.
`
`––––––––––––––––––
`
`Case No. IPR2015-010461
`U.S. Patent No. 6,502,135
`
`––––––––––––––––––
`
`PETITIONERS’ REMAND BRIEF
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`
`
`1 Apple Inc., who filed a petition in IPR2016-00062, has been joined as a Petitioner
`in the instant proceeding.
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`

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`IPR2015-01046
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`U.S. Patent No. 6,502,135
`
`TABLE OF CONTENTS
`
`I.
`II.
`
`Introduction ................................................................................................ 1
`The Federal Circuit’s Decision ................................................................... 3
`A. VirnetX’s Patentability Arguments for the ’135 Patent ....................... 3
`B.
`VirnetX’s Procedural Arguments ........................................................ 5
`III. Claim Construction ..................................................................................... 6
`A.
`“Client Computer” .............................................................................. 6
`B.
`“Direct” Communication .................................................................... 9
`IV. The Challenged Claims Are Anticipated under Both of the Petition’s
`Kiuchi Mappings ....................................................................................... 11
`A.
`The First Mapping: User Agent to Origin Server .............................. 13
`1.
`Overview of the First Kiuchi Mapping .................................... 13
`2.
`Kiuchi’s User Agent Communicates “Directly” with the Origin
`Server ..................................................................................... 18
`The Second Mapping: Client-Side Proxy to Server-Side Proxy ........ 24
`1.
`Overview of the Second Kiuchi Mapping ............................... 24
`2.
`Kiuchi’s Client-Side Proxy Is a “Client Computer” ................ 26
`Petitioner Mangrove Was Not Time-Barred Under Section 315(b) ....... 30
`A.
`There Was No Conspiracy Between Mangrove and RPX or Apple ... 31
`B. Mangrove’s Purchases of RPX Stock Do Not Implicate § 315(B)..... 33
`1. Mangrove’s Stock Purchases Do Not Make RPX or Apple
`RPIs ........................................................................................ 34
`2. Mangrove’s Stock Purchases Do Not Make RPX or Apple
`Privies ..................................................................................... 36
`VI. Conclusion ................................................................................................. 37
`Exhibit List .......................................................................................................... 39
`Certificate of Compliance ................................................................................... 43
`Certificate of Service........................................................................................... 44
`
`
`
`B.
`
`V.
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`U.S. Patent No. 6,502,135
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`TABLE OF AUTHORITIES
`
` Page(s)
`
`Cases
`Applications in Internet Time, LLC v. RPX Corp.,
`897 F.3d 1336 (Fed. Cir. 2018) ........................................................................ 34
`Dr. Reddy’s Labs. v. Indivior UK Ltd.,
`IPR2019-00329, Paper 21 (PTAB June 3, 2019) ........................................ 34, 35
`
`Gillig v. Nike, Inc.,
`602 F.3d 1354 (Fed. Cir. 2010) ........................................................................ 37
`In re Gleave,
`560 F.3d 1331 (Fed. Cir. 2009) ........................................................................ 27
`National Ass’n of Home Builders v. Defenders of Wildlife,
`551 U.S. 644 (2007) ........................................................................................... 5
`Power Integrations, Inc. v. Semiconductor Components Indus., LLC,
`926 F.3d 1306 (Fed. Cir. 2019) ........................................................................ 30
`RPX Corp. v. Publishing Techs., LLC,
`IPR2018-01131, Paper 10 (PTAB Dec. 3, 2018) .............................................. 37
`Taylor v. Sturgell,
`553 U.S. 880 (2008) ......................................................................................... 36
`TRW Automotive US LLC v. Magna Elecs. Inc.,
`Case IPR2014-01499, Paper 7 (PTAB Mar. 19, 2015) ..................................... 36
`Unified Patents, Inc. v. Carucel, L.P.,
`IPR2019-01079, Paper 9 (PTAB Nov. 12, 2019) ............................................. 34
`Unified Patents, Inc. v. Realtime Adaptive Streaming, LLC,
`IPR2018-00883, Paper 36 (PTAB Oct. 11, 2018) ............................................ 35
`Ventex Co. v. Columbia Sportswear N. Am., Inc.,
`IPR2017-00651, Paper 148 (PTAB Jan. 24, 2019) ..................................... 34, 35
`VirnetX Inc. v. Mangrove Partners Master Fund, Ltd.,
`778 F. App’x 897 (Fed. Cir. 2019) ..................................................................... 1
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`VirnetX, Inc. v. Cisco Sys., Inc.,
`767 F.3d 1308 (Fed. Cir. 2014) ........................................................................ 28
`WesternGeco LLC v. ION Geophysical Corp.,
`889 F.3d 1308 (Fed. Cir. 2018) ........................................................................ 36
`Wi-Fi One, LLC v. Broadcom Corp.,
`878 F.3d 1364 (Fed. Cir. 2018) (en banc) ........................................................ 30
`Statutes
`35 U.S.C. § 315(b) ......................................................................................... passim
`
`
`
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`IPR2015-01046
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`I.
`
`Introduction
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`U.S. Patent No. 6,502,135
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`In its Final Written Decision (Paper 71, “Final Decision”), the Board
`
`correctly concluded that claims 1, 3-4, 7-8, 10, and 12 of the ’135 patent
`
`(“challenged claims”) are unpatentable. Patent Owner VirnetX Inc. (“VirnetX”)
`
`appealed, and on July 8, 2019, the U.S. Court of Appeals for the Federal Circuit
`
`vacated the Final Decision and remanded for further consideration of certain
`
`issues. VirnetX Inc. v. Mangrove Partners Master Fund, Ltd., 778 F. App’x 897
`
`(Fed. Cir. 2019) (“CAFC Dec.”). None of those remanded issues warrants the
`
`Board reaching a different determination.
`
`First, Kiuchi anticipates the challenged claims because the communications
`
`between Kiuchi’s user agent (a “client computer”) and origin server (a “target
`
`computer”) are “direct.” Most notably, requests in Kiuchi’s system directly address
`
`the desired server and resource, and thus satisfy even VirnetX’s opaque definition
`
`of “direct” communications. And while VirnetX has criticized the Kiuchi system
`
`for using proxies that supposedly “break” these “direct” communications between
`
`Kiuchi’s user agent and origin server, those criticisms ring hollow—VirnetX’s
`
`expert admitted that examples in the ’135 patent itself using operations
`
`indistinguishable from those in Kiuchi’s system do not “break” direct
`
`communications. VirnetX does not dispute that Kiuchi’s user agent is a “client
`
`computer” even under its narrow construction, so the only finding the Board need
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`make to establish anticipation is that Kiuchi discloses “direct” communications
`
`between the two claimed components. It plainly does.
`
`Second, Kiuchi anticipates the challenged claims under Petitioners’
`
`alternative anticipation mapping where Kiuchi’s client-side proxy is the “client
`
`computer.” For this mapping, VirnetX does not dispute that communications
`
`between Kiuchi’s client- and server-side proxies are “direct.” The only issue to be
`
`decided under this mapping, then, is whether Kiuchi’s client-side proxy is a “client
`
`computer” under a proper construction of that term. It plainly is—it fits within the
`
`plain and ordinary meaning of a client computer, and matches how the ’135 patent
`
`itself uses this term. And VirnetX’s assertions to the contrary must be rejected—its
`
`assertion that a “client computer” can only be a “user’s computer” conflicts with
`
`the intrinsic evidence and what its own expert said was the ordinary meaning of the
`
`term, and it is undisputed that the ’135 patent did not redefine “client computer” to
`
`have a special meaning.
`
`Finally, nothing supports VirnetX’s challenge to Mangrove’s compliance
`
`with § 315(b). VirnetX’s latest theory appears to be that third-party RPX
`
`Corporation (“RPX”) and/or Petitioner Apple are co-conspirators who directed
`
`Mangrove to file this IPR at their behest. The additional discovery granted of
`
`Mangrove conclusively disproves this theory: RPX had absolutely no involvement
`
`in Mangrove’s filings and Mangrove’s RPX stock purchases were unrelated to this
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`proceeding. There is simply no RPI or privy relationship between Mangrove and
`
`RPX or Apple that could implicate § 315(b). Thus, the Board should again find the
`
`challenged claims unpatentable.
`
`II. The Federal Circuit’s Decision
`
`The Board’s Final Decision found every challenged claim in the ’135 patent
`
`unpatentable. VirnetX appealed to the Federal Circuit, and advanced both
`
`procedural and patentability arguments. See Br. for Appellant VirnetX Inc., No.
`
`2017-1368, Dkt. No. 45 (Fed. Cir. Apr. 2, 2018) (“PO CAFC Br.”); Reply Br. for
`
`Appellant VirnetX Inc., No. 2017-1368, Dkt. No. 70 (Fed. Cir. June 19, 2018)
`
`(“PO CAFC Reply Br.”). The Federal Circuit’s decision dismissed many of these
`
`arguments, but vacated the Board’s final decision and remanded for the Board to
`
`address a limited number of issues.
`
`A. VirnetX’s Patentability Arguments for the ’135 Patent
`
`VirnetX advanced numerous arguments why it believed Kiuchi did not
`
`anticipate the challenged claims. See Paper 44 (“Resp.”), 18-37; Paper 67 (“Sur-
`
`Reply”), 2-11. On appeal, however, VirnetX advanced only two.
`
`First, VirnetX contended the claim term “client computer” must be
`
`construed to be only a “user’s computer,” and that the Board erred by finding
`
`Kiuchi’s client-side proxy to be a “client computer.” PO CAFC Br. 44-45; see id.,
`
`38-43. The Court then faulted the Board for not explicitly construing “client
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`computer” in connection with Petitioners’ mapping of Kiuchi’s client-side proxy as
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`the “client computer” and for taking VirnetX’s proposed construction “out of
`
`context.” CAFC Dec. 908-09. But it ultimately decided that the Board should
`
`construe “client computer” on remand, instructing it to “analyz[e] the language of
`
`[VirnetX’s] proposed construction ….”2 Id..
`
`Second, VirnetX argued, and the Court agreed, that the Board should have
`
`construed a “VPN between the client computer and the target computer” as
`
`requiring “direct” communication between the client computer and the target
`
`computer. Id., 908-10. The Court held that “[t]he statements VirnetX made during
`
`reexamination” regarding the Aventail reference “constitute disclaimer,” and that a
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`“VPN between the client computer and the target computer” requires “direct
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`communication between the client and target computers.” Id., 910. The Court,
`
`however, left to the Board on remand the task of “assess[ing] Kiuchi’s disclosure
`
`in light of the proper construction in the first instance,” including whether its
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`systems use “direct” communications. Id.
`
`
`
`2 The Court confirmed that Petitioners had “advanced alternative theories in their
`
`petitions, one of which was that the user agent meets the limitations of the ‘client
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`computer,’” and that VirnetX was provided adequate notice and opportunity to
`
`respond. CAFC Dec. 909.
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`B. VirnetX’s Procedural Arguments
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`The Federal Circuit also addressed VirnetX’s procedural objections. First, it
`
`rejected VirnetX’s assertion that Petitioner Apple’s joinder to these proceedings
`
`violates 35 U.S.C. § 315(b). CAFC Dec. 901-03. The Court found the issue raised
`
`by VirnetX to be, at most, harmless error, and “decline[d] to decide whether
`
`Apple’s joinder was permitted under § 315(b)-(c) because VirnetX has not
`
`demonstrated that it was prejudiced by Apple’s involvement.” Id., 901; see, e.g.,
`
`National Ass’n of Home Builders v. Defenders of Wildlife, 551 U.S. 644, 659-660
`
`(2007).
`
`The Court also found that substantial evidence supported the Board’s
`
`conclusion that Mangrove Partners Hedge Fund was not an RPI. Id., 902-03. The
`
`Court noted that even if the hedge fund was an RPI, nothing prevented Petitioner
`
`Mangrove from curing noncompliance with § 312(a)(2) given that the hedge fund
`
`is not time-barred under § 315(b). Id., 903.
`
`Finally, the Court found that “the Board abused its discretion by refusing to
`
`allow VirnetX to … file a motion for additional discovery into the connection
`
`between Mangrove and RPX.” Id., 904; see PO CAFC Br. 64. The Court did not,
`
`however, “express a view on the merits of such a motion should VirnetX file one
`
`on remand.” CAFC Dec. 904.
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`III. Claim Construction
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`U.S. Patent No. 6,502,135
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`As the Federal Circuit observed, the Board should “resolve the claim
`
`construction dispute as to the meaning of ‘client [computer]’” as it pertains to
`
`Petitioners’ second anticipation mapping (i.e., where the client-side proxy is the
`
`“client computer”). See CAFC Dec. 908. Petitioners’ first anticipation mapping
`
`does not implicate this issue—there, the “user agent” is the “client computer.”
`
`The Federal Circuit also construed a “VPN between the client computer and
`
`the target computer” to require “direct” communication between the client and
`
`target computers. Id., 908-10. It did not define, however, what is required for a
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`communication to be “direct,” and directed the Board to determine whether the
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`communications between Kiuchi’s user agent and origin server meet that
`
`requirement. Petitioners’ second anticipation mapping does not implicate this
`
`issue—there is no dispute that communications between Kiuchi’s client-side and
`
`server-side proxies are “direct.”
`
`A.
`
`“Client Computer”
`
`Based on its ordinary meaning and use throughout the ’135 patent, a “client
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`computer” is a “computer from which a data request to a server is generated.”
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`Paper 5 (“Pet.”) at 16.3 As Dr. Guerin explained, a skilled person would have
`
`understood a “client computer” to refer to the conventional client component of a
`
`client/server architecture.4 Ex. 1003, ¶19; Ex. 1014, 5. Both experts agreed that a
`
`skilled person would have understood a conventional “client” to be any application
`
`that generates a request for data from a server. Ex. 1003, ¶19; Ex. 1036, 97:8-15,
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`101:1-10. And that is precisely how the ’135 patent uses the term “client”—it
`
`repeatedly refers to any “client application” (including a “web browser”) that
`
`makes requests for information from a server. Ex. 1001, 37:30-32, 38:15-18.
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`VirnetX nonetheless contended that the ’135 patent equates a “client computer”
`
`with a “user’s computer.” Resp. 8-10. That is incorrect for several reasons.
`
`
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`3 The Petition in the proceeding involving the related ’151 patent proposed that
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`“client” be construed as “a device, computer, system, or program from which a
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`data request to a server is generated.” IPR2015-01047, Paper 5 at 15. Here, the
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`claims require a “client computer.”
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`4 Numerous dictionaries confirm Dr. Guerin’s opinion, including ones cited by
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`VirnetX. Ex. 2028, 3; Ex. 1014, 5; Ex. 1037, 11; Ex. 1043, 88; accord IPR2014-
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`00404, Paper 42, 8-9.
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`U.S. Patent No. 6,502,135
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`First, as Dr. Monrose testified, the ’135 patent does not expressly redefine
`
`the term “client” or “client computer” to have a meaning different from its ordinary
`
`meaning. See Ex. 1036, 74:15-75:16, 95:1-6. VirnetX also has not contended that
`
`any prosecution history caused this term to have a special meaning. Given both
`
`points, it would be legal error to interpret “client computer” differently from its
`
`plain and ordinary meaning. And this is true whether the claims are assessed with
`
`their broadest reasonable interpretation or as by a district court.5
`
`Second, VirnetX’s assertion that “client computer” means only a “user’s
`
`computer” is contrary to the intrinsic record. When the ’135 patent refers to a user
`
`or a user’s computer, it uses those terms explicitly, expressly distinguishing the
`
`“user’s computer” from a “conventional client,” noting that the latter can be
`
`included in the former. See, e.g., Ex. 1001, Fig. 26 (item 2601), 38:14-15 (“A
`
`user’s computer 2601 includes a 15 conventional client (e.g., a web browser)
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`2605 …”); 37:30-32; 39:17-20 (“The user's security level can also be determined
`
`by transmitting a request message back to the user’s computer …”); 39:22-29 (“…
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`in step 2706 a secure VPN is established between the user’s computer and the
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`secure target site … by allocating a hopping regime that will be carried out
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`
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`5 The ’135 patent will expire in February of 2020.
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`between the user’s computer and the secure target site …”); 44:40-45.6 Thus, the
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`’135 patent does not use “client computer” synonymously with “user’s
`
`computer”—when it refers to the “user’s computer,” it does so explicitly, and
`
`when it refers to “client” or “client computer,” it uses those terms with their
`
`ordinary meaning. Id.
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`Finally, the ’135 patent describes several embodiments where a VPN is
`
`initiated by a “client” that is not running on a computer portrayed as being
`
`operated by a user. Ex. 1001, 38:14-15, 38-44. For example, the ’135 patent
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`discloses embodiments where a VPN is established between two computers
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`described simply as a “first and second computer” and not showing any user
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`involvement (Id., 31:57-64, 36:26-28, Figs. 20, 24), as well as examples that refer
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`only to two “host computer[s],” (id., 40:27-30, Figs. 28, 29). Those examples
`
`reinforce that a “client computer” is (consistent with its ordinary meaning) simply
`
`“a computer from which a data request to a server is generated”—it does not have
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`to be a “user’s” computer. See IPR2014-00404, Paper 42, 15-16; Pet. 16.
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`B.
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`“Direct” Communication
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`Although the Federal Circuit found that a “VPN between a client computer
`
`and a target computer” requires “direct” communication between the client and
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`
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`6 All emphasis added unless otherwise noted.
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`target (CAFC Dec. 908-10), it did not define that term. Likewise, in these
`
`proceedings, VirnetX has never articulated what the requirements for a “direct”
`
`communication are—when VirnetX’s counsel was pointedly asked at oral
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`argument for a definition, he could not provide one. Paper 70, 60:11-22. Likewise,
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`VirnetX’s expert Dr. Monrose testified he did not know and said whether a
`
`reference discloses a “direct” communication was a “judgment call.” Ex. 1036,
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`261:20-262:9, 263:3-20.
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`The only time VirnetX has ever suggested what a “direct communication”
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`requires was during the concurrent litigation between it and Apple, where
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`VirnetX’s expert testified that direct communication refers to direct addressability
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`of the target computer:
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`Q… A secure communication link must be a direct communication
`link. And I believe that you've told us that direct communication
`refers to direct addressability, correct?
`
`A. That’s correct.
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`Ex. 1044, 50:25-51:5.
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`While VirnetX and its expert, Dr. Monrose, have never affirmatively stated
`
`what direct communications are, the latter has admitted that several examples of
`
`communications depicted in the ’135 patent disclosure use “direct”
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`communication. Resp. 7-12, Ex. 2043, ¶¶20-21. These examples show a diverse
`
`array of network communications that use different types of operations (e.g.,
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`encryption/decryption, wrapping/unwrapping) and transit many different paths
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`(e.g., through ISPs, firewalls, and/or routers), yet do not “break” direct
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`communication. Ex. 1001, 7:40-49, 12:59-13:40, Fig. 24. In one example, “direct”
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`communications between two hosts (“host 1” and “host 2”) transit two separate
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`VPNs – a first VPN between host #1 and an ISP and a second, “separate VPN”
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`between the ISP and host #2. Ex.1001, 41:56-65, Fig. 29.
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`By this standard, the communications that occur between the “user agent”
`
`and the “origin server” in Kiuchi’s system are “direct communications.” As
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`explained further below, those communications employ direct addressing and use
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`conventional techniques analogous to the ’135 patent’s examples that, according to
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`VirnetX’s expert, do not “break” direct communication.
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`IV. The Challenged Claims Are Anticipated under Both of the Petition’s
`Kiuchi Mappings
`
`The Petition demonstrated that Kiuchi anticipates each of the challenged
`
`claims of the ’135 patent.7 It presented two mappings of elements of the Kiuchi
`
`system to the requirements of the claims. In the first mapping, Kiuchi’s user agent
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`
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`7 On appeal, VirnetX addressed claim 1 and did not advance separate patentability
`
`arguments for the remaining challenged claims. Thus, those claims rise and fall
`
`with claim 1.
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`is the “client computer” and generates requests for information stored on an origin
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`server (the “target computer”):
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`
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`Pet. 26-27; Reply 8-11.
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`In the second mapping, the Petition identified Kiuchi’s client-side proxy as
`
`the “client computer,” and showed that it generates C-HTTP requests for
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`information from the server-side proxy (the “target computer”):
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`
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`Pet. 26-27; Reply 8-11.
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`U.S. Patent No. 6,502,135
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`The Petition also explained how each “client computer” “directly”
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`communicated with its corresponding “target computer”:
`
` (1)
`
`the user agent sends HTTP requests directly addressed to the origin
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`server (a “target computer”), and
`
`(2)
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`the client-side proxy sends IP messages directly addressed to the
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`server-side proxy (another “target computer”).
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`Pet. 26-29; Reply 13-16. As explained further below, each of these mappings
`
`independently satisfies these elements of the claims. Any arguments to the contrary
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`must be limited to those VirnetX raised in its Patent Owner Response (Paper 44),
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`Sur-Reply (Paper 67), or CAFC Appeal Brief. See Paper 12, 3.
`
`A. The First Mapping: User Agent to Origin Server
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`VirnetX has contended that Kiuchi’s user agent–origin server mapping does
`
`not anticipate the challenged claims because Kiuchi’s user agent does not
`
`communicate “direct[ly]” with the origin server. VirnetX’s arguments cannot be
`
`reconciled with what Kiuchi discloses, the testimony of its experts, and the
`
`examples in the ’135 patent that involve “direct” communication.
`
`1.
`
`Overview of the First Kiuchi Mapping
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`As the Petition explains, Kiuchi’s user agent (a “client computer”) generates
`
`an HTTP/1.0 Get Request for a resource identified in part by a hostname (a “DNS
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`request”). Ex. 1002, 65 (§2.3); Pet. 27. Kiuchi shows that this request includes a
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`URL that contains information identifying both the server-side proxy and the
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`origin server: it contains the hostname of the server-side proxy
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`(“server.in.current.connection”) and a resource that is resident on the origin server
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`(“sample.html”):
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`
`
`Ex. 1002, 65 (§1), 66 (Figures),
`
`The user agent sends the HTTP/1.0 Get Request to the client-side proxy,
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`which receives the request and evaluates the hostname in the URL to determine
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`where to send the Get Request next. Ex. 1002, 65 (§1), 66 (Figures). It does this by
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`sending the hostname to the C-HTTP name server: if the hostname corresponds to
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`a server-side proxy registered with the closed network, the C-HTTP name server
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`returns the public IP address of the server-side proxy along with other information
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`needed to establish an encrypted C-HTTP connection. Id., 65 (§2), 73.
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`After the encrypted C-HTTP connection is established, the client-side proxy
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`encrypts the HTTP/1.0 Get Request and wraps that message within a C-HTTP
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`request message, as shown below.
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`Id., 74-75; see id., 66 (HTTP/1.0 request encrypted and wrapped in C-HTTP
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`request”).
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`The client-side proxy then sends the C-HTTP request to the server-side
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`proxy, which extracts the HTTP/1.0 Get Request and decrypts it, id., 66 (§7),
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`yielding the original URL generated by the user agent:
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`The server-side proxy inspects the URL and forwards the Get Request to the
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`origin server. Id., 66 (§7). In response, the origin server sends an HTTP Response
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`with the requested resource back the user agent. Id., 66 (§8). The origin server does
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`this by transmitting the HTTP Response to the server-side proxy, which encrypts it
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`and wraps it in a C-HTTP message, as shown below. Id., 75.
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`The server-side proxy sends the C-HTTP message to the client-side proxy, which
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`decrypts the HTTP Response and forwards it to the user agent. Ex. 1002, 66 (§8).
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`While this example involves retrieval of an HTML file, any other type of
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`resource stored on the origin server can be specified, such as an image file (e.g.,
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`sample.jpg). Id., 67 (discussing “image and sound data”). If a user wanted to
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`retrieve a picture (“sample.jpg”) stored on the origin server, the GET request
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`would specify that file in the URL (e.g., “GET
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`http://server.in.current.connection/sample.jpg” HTTP/1.0<CR><LF>”), and the
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`“sample.jpg” file (in unmodified form) would then be sent within the response
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`message to the user agent. See id., 65 (§8); Ex. 1036, 230:9-12, 274:7-281:15.
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`The Petition also explained how this functionality and Kiuchi’s components
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`satisfied each requirement of independent claim 1. It explained that Kiuchi
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`discloses a “method of transparently creating” an encrypted C-HTTP connection
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`(“a virtual private network (VPN)”) between the user agent (“a client computer”)
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`and the origin server (a “target computer”). Pet. 26-27; Ex. 1002, 65 (§2.2).
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`Kiuchi’s user agent generates an HTTP request that includes a URL identifying a
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`resource located on the origin server, and because the URL address in the request
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`includes a hostname of the server-side proxy, it thus performs the step of “(1)
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`generating from the client computer a Domain Name Service (DNS) request that
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`requests an IP address corresponding to a domain name associated with the target
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`computer.” Pet. 27; Ex. 1002, 65 (§2.2); Ex. 1003, ¶¶20-22.
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`Kiuchi’s client-side proxy will then, in concert with the C-HTTP name
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`server, determine whether the host specified in the URL is registered in the closed
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`network and whether the user agent can communicate with it. Ex. 1002, 65 (§ 2.3);
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`Pet. 28-29; Ex. 1003, ¶¶23-24. If the host is registered and the user agent is
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`authorized, the C-HTTP server sends the client-side proxy “the IP address and
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`public key of the server-side proxy and both request and response Nonce values.”
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`Ex. 1002, 65 (§ 2.3); Pet. 29. Kiuchi thus discloses the steps of “(2) determining
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`whether the DNS request transmitted in step (1) is requesting access to a secure
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`web site” and “(3) in response to determining that the DNS request in step (2) is
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`requesting access to a secure target web site ….”
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`Finally, if the client-side proxy determines that the server side proxy is
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`registered in the closed network, it automatically establishes an encrypted C-HTTP
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`connection between the client-side and server-side proxies, allowing the user agent
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`and the origin server, located on their own secure private networks, to securely
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`communicate (“automatically initiating the VPN between the client computer and
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`the target computer”). Ex. 1002, 65 (§§ 2.2-2.3); Pet. 29-31; Ex. 1003, ¶¶23-31.
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`VirnetX has conceded that Kiuchi’s user agent is a “user’s computer” and
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`thus satisfies its own, narrow construction of “client computer.” Resp. 25. The only
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`remaining dispute is whether Kiuchi’s user agent communicates “directly” with the
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`secure server. It does.
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`2.
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`Kiuchi’s User Agent Communicates “Directly” with the Origin
`Server
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`As explained in § III.B, the word “direct” must at least encompass
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`communications where the request from the client directly addresses the target
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`computer. Ex.1044, 50:25-51:5. Kiuchi meets that definition. When it issues an
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`HTTP Get Request, the user agent in Kiuchi specifies the address of the resource
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`on the origin server via the URL. Ex. 1002, 65 (§1), 66 (Figures). VirnetX’s expert
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`Dr. Monrose admitted that Kiuchi’s URL contains the actual address of the
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`resource on the origin server. Ex. 1036, 240:21-241:14. This HTTP Get Request is
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`routed across several devices and then delivered to the origin server. Ex. 1002, 65-
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`66. Thus, communications between Kiuchi’s user agent and the origin server are
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`“direct” communications because the user agent can communicate with the origin
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`server by directly addressing the origin server.
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`VirnetX asserts that operations performed by Kiuchi’s client-side and server-
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`side proxies somehow break the “direct” communications between the user agent
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`and the origin server by “stopping communication [], wrapping/unwrapping
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`messages, encrypting/decrypting their contents, re-formatting, and ultimately re-
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`sending messages.” Resp. 31. But VirnetX’s arguments cannot be reconciled with
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`the ’135 patent’s disclosure or the admissions of its expert, which establish that
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`operations indistinguishable from those performed by Kiuchi’s system do not
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`break “direct” communications.
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`For example, the ’135 patent describes communications mediated by TARP
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`routers,8 which VirnetX’s expert, Dr. Monrose, admitted perform direct
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`communications. Ex. 2043, ¶¶20-21; Ex. 1036, 43:2-9, 79:9-81:11. These TARP
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`routers (i) encrypt messages and “wrap” them with another header before
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`transmission, and then (ii) decrypt and unwrap the messages upon receipt before
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`sending the data to another destination. Ex. 1001, Figs. 1, 2, 3A, 4, 13, 20, 24;
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`10:48-54, 13:33-38, 20:51-56; Ex. 1036, 130:7-20.
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`
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`8 TARP routers act as “proxy” devices because they receive and send
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`communications from the user’s computer that are addressed to a different target
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`computer. See Ex. 1014, 5 (defining “proxy”).
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`Kiuchi’s system works the same way. When a user agent sends an HTTP/1.0
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`GET Request addressed to the origin server, the client-side proxy receives the GET
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`Request, encrypts it, “wraps” the encrypted request in a C-HTTP message, and
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`forwards it to the server-side proxy. Ex. 1002, 66, Fig. (c) (the “HTTP/1.0 request
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`[is] encrypted and wrapped in a C-HTTP request”), §2.3(6) (“a client-side proxy
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`forwards HTTP/1.0 requests”). The server-side proxy receives the C-HTTP
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`message, unwraps and decrypts the HTTP/1.0 message, and forwards it to the
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`origin server. Id., §2.3(8) (“the C-HTTP response is decrypted and the HTTP/1.0
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`response extracted”). Kiuchi’s client-side proxy thus receives the GET Request
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`from the user agent and processes it in the same way that TARP routers do in the
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`’135 patent.
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`Other passages in the ’135 patent likewise show use conventional operations
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`by proxies or routers that VirnetX contends do not “break”