Case 6:10-cv-00417-LED Document 173 Filed 11/04/11 Page 1 of 36 PageID #: 2653
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`IN THE UNITED STATES DISTRICT COURT
`FOR THE EASTERN DISTRICT OF TEXAS
`TYLER DIVISION
`
`Plaintiff,
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`VIRNETX, INC.,
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`
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`vs.
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`CISCO SYSTEMS, INC., et al.
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`
`
`
`Defendants.
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`
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`§
`§
`§
`§
`§
`§
`§
`§
`§
`§
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`Civil Action No. 6:10-cv-417
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`JURY TRIAL DEMANDED
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`VIRNETX’S OPENING CLAIM CONSTRUCTION BRIEF
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`
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`
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`Petitioner Apple Inc. - Ex. 1042, Cover
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`Case 6:10-cv-00417-LED Document 173 Filed 11/04/11 Page 2 of 36 PageID #: 2654
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`
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`I.
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`II.
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`III.
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`IV.
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`TABLE OF CONTENTS
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`TECHNOLOGY OVERVIEW............................................................................................1
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`PRINCIPLES OF CLAIM CONSTRUCTION ...................................................................2
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`LEVEL OF ORDINARY SKILL IN THE ART .................................................................3
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`DISPUTED CLAIM CONSTRUCTIONS ..........................................................................3
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`A.
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`Disputes Concerning Types of Communication Links............................................3
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`1.
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`2.
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`3.
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`“virtual private network” [included in asserted
`claims of the ’135, ’180, and ’759 patents] .................................................3
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`“virtual private link” [included in asserted claims of
`the ’135 patent] ............................................................................................9
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`“secure communication link” [included in asserted
`claims of the ’504, ’211, and ’759 patents] ...............................................10
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`B.
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`Disputes Concerning Domain Name, Domain Name
`Service, Secure Domain Name, etc........................................................................13
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`1.
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`2.
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`3.
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`4.
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`5.
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`6.
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`“domain name service” [included in asserted claims
`of the ’135, ’180, ’504, and ’211 patents]..................................................13
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`“domain name” [included in asserted claims of the
`’135, ’180, ’504, and ’211 patents]............................................................14
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`“DNS proxy server” [included in asserted claims of
`the ’135 patent] ..........................................................................................16
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`“secure domain name service” [included in asserted
`claims of the ’180 patent] ..........................................................................17
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`“domain name service system” [included in asserted
`claims of the ’504 and ’211 patents]..........................................................19
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`“top-level domain name” [included in asserted
`claims of the ’504 and ’211 patents]..........................................................20
`
`C.
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`Disputes Concerning Web Site, Secure Web Site, Secure
`Web Computer, etc. ...............................................................................................21
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`1.
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`“web site” [included in asserted claims of the ’135
`patent] ........................................................................................................21
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`McKool 401908v2
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`i
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`Petitioner Apple Inc. - Ex. 1042, p. i
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`2.
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`3.
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`4.
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`5.
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`6.
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`“secure web site” [included in asserted claims of the
`’135 patent] ................................................................................................21
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`“secure target web site” [included in asserted claims
`of the ’135 patent]......................................................................................21
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`“secure web computer” [included in asserted claims
`of the ’135 patent]......................................................................................22
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`“secure server” [included in asserted claims of the
`’151 patent] ................................................................................................24
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`“target computer” [included in asserted claims of
`the ’135 patent] ..........................................................................................24
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`D.
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`Disputes Concerning Defendants’ Attempt to Rewrite the
`Claims ....................................................................................................................26
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`1.
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`2.
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`3.
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`4.
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`5.
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`6.
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`“between [A] and [B]” [included in asserted claims
`of the ’135, ’151, ’504, ’211, and ’759 patents] ........................................26
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`“determining whether the DNS request transmitted
`in step (1) is requesting access to a secure web site”
`[included in asserted claims of the ’135 patent] ........................................26
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`“generating from the client computer a Domain
`Name Service (DNS) request” [included in asserted
`claims of the ’135 patent] ..........................................................................26
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`“an indication that the domain name service system
`supports establishing a secure communication link”
`[included in asserted claims of the ’504 patent] ........................................26
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`“indicate/indicating… whether the domain name
`service system supports establishing a secure
`communication link” [included in asserted claims of
`the ’211 patent] ..........................................................................................26
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`“enabling a secure communication mode of
`communication” [included in asserted claims of the
`’759 patent] ................................................................................................27
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`E.
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`Miscellaneous Dispute...........................................................................................28
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`1.
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`“cryptographic information” [included in asserted
`claims of the ’759 patent] ..........................................................................28
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`V.
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`CONCLUSION..................................................................................................................29
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`McKool 401908v2
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`ii
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`Petitioner Apple Inc. - Ex. 1042, p. ii
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`Case 6:10-cv-00417-LED Document 173 Filed 11/04/11 Page 4 of 36 PageID #: 2656
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`
`FEDERAL CASES
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`TABLE OF AUTHORITIES
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`PAGE(S)
`
`AIA Eng’g Ltd. v. Magotteaux Int’l S/A,
`2011 U.S. App. LEXIS 18125 (Fed. Cir. Aug. 31, 2011) .......................................................20
`
`Bd. of Regents of the Univ. of Tex. Sys. v. BENQ Am. Corp.,
`533 F.3d 1362 (Fed. Cir. 2008)................................................................................................20
`
`Clearwater Sys. Corp. v. Evapco, Inc.,
`394 Fed. Appx. 699 (Fed. Cir. 2010)............................................................................... passim
`
`E-Pass Techs., Inc. v. 3COM Corp.,
`343 F.3d 1364 (Fed. Cir. 2003)........................................................................................ passim
`
`Eon-Net LP v. Flagstar Bancorp,
`653 F.3d 1314 (Fed. Cir. Jul. 29, 2011).....................................................................................9
`
`Globetrotter Software, Inc. v. Elan Computer Group, Inc.,
`362 F.3d 1367 (Fed. Cir. 2004)................................................................................................16
`
`Grantley Patent Holdings, Ltd. v. Clear Channel Communs., Inc.,
`2008 U.S. Dist. LEXIS 1588 (E.D. Tex. Jan. 8, 2008) (Clark, J.)...........................................27
`
`i4i Ltd. P’ship v. Microsoft Corp.,
`598 F.3d 831 (Fed. Cir. 2010)......................................................................................11, 25, 27
`
`Johnson Worldwide Assocs., Inc. v. Zebco Corp.,
`175 F.3d 985 (Fed. Cir. 1999)..................................................................................................20
`
`MBO Labs., Inc. v. Becton, Dickinson & Co.,
`474 F.3d 1323 (Fed. Cir. 2007)................................................................................................20
`
`Momentus Golf, Inc. v. Swingrite Golf Corp.,
`187 Fed. Appx. 981 (Fed. Cir. 2006).........................................................................................8
`
`Nazomi Communications, Inc. v. ARM Holdings, PLC,
`403 F.3d 1364 (Fed. Cir. 2005)..................................................................................................2
`
`Omega Eng’g, Inc. v. Raytek Corp.,
`334 F.3d 1314 (Fed. Cir. 2003)........................................................................................ passim
`
`Phillips v. AWH Corp.,
`415 F.3d 1303 (Fed. Cir. 2005)............................................................................................2, 22
`
`Rheox, Inc. v. Entact, Inc.,
`276 F.3d 1319 (Fed. Cir. 2002)..............................................................................................7, 8
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`McKool 401908v2
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`iii
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`Petitioner Apple Inc. - Ex. 1042, p. iii
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`Case 6:10-cv-00417-LED Document 173 Filed 11/04/11 Page 5 of 36 PageID #: 2657
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`Vitronics Corp. v. Conceptronic,
`90 F.3d 1576 (Fed. Cir. 1996)..................................................................................................21
`
`Zircon Corp. v. Stanley Black & Decker, Inc.,
`2011 U.S. App. LEXIS 20164 (Fed. Cir. Oct. 5, 2011).............................................................9
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`McKool 401908v2
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`iv
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`Petitioner Apple Inc. - Ex. 1042, p. iv
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`Case 6:10-cv-00417-LED Document 173 Filed 11/04/11 Page 6 of 36 PageID #: 2658
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`I. TECHNOLOGY OVERVIEW
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`There are six patents at issue in this lawsuit: U.S. Patent Nos. 6,502,135 (the ’135 patent),
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`6,839,759 (the ’759 patent), 7,188,180 (the ’180 patent), 7,418,504 (the ’504 patent), 7,490,151
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`(the ’151 patent), and 7,921,211 (the ’211 patent). The patents are attached in Exhibits 1-6.
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`The Court has previously construed terms for the ’135, ’759, and ’180 patents in VirnetX
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`Inc. v. Microsoft Corp., Civ. No. 6:07-cv-80 (E.D. Tex.). The Court’s claim construction
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`opinion from the Microsoft litigation is attached at Ex. A. The new patents belong to the same
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`family of patent applications.1 As such, the technology at issue in the new patents will be
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`familiar to the Court.
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`The patents are all concerned with secure communications. At a high level, the ’135
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`patent discloses and claims systems and methods that create a virtual private network (VPN)
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`based on a DNS request. Similarly, the ’504 and ’211 patents disclose and claim a domain name
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`service system for establishing a secure communication link, and the ’151 patent discloses and
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`claims a domain name system that establishes an encrypted channel based on a DNS request.
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`The ’759 patent discloses and claims systems and methods that establish a VPN link using DNS
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`without a user entering cryptographic information, such as encryption keys. The ’180 patent
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`discloses and claims systems and methods for a secure domain name service.
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`These inventions solve several problems known in the prior art. For example, the prior
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`art required a user to manually set up the VPN e.g., manually configuring the cryptographic keys
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`required to encrypt and decrypt the messages. Manually-created VPNs were neither flexible nor
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`easy to use. And business travelers trying to remotely connect to their corporate networks
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`1 Specifically, the ’211 patent is a continuation of the ’504 patent, which is itself a continuation
`of a continuation-in-part of the application that became the ’135 patent. The ’151 patent is a
`division of the ’135 patent application.
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`VIRNETX’S OPENING CLAIM CONSTRUCTION BRIEF
`McKool 401908v2
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`PAGE 1 OF 29
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`Petitioner Apple Inc. - Ex. 1042, p. 1
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`through VPNs had difficulty setting up and using VPNs. See ’135::2:52-63. The inventions of
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`the patents-in-suit made it easier to create VPNs and other secure communication links. This is
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`an immense benefit to both users and computers that establish VPNs considering that, in the
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`prior art, VPN and other secure communications that were difficult to set up were infrequently
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`used, leaving sensitive communications unprotected.
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`II. PRINCIPLES OF CLAIM CONSTRUCTION
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`VirnetX proposes constructions of the claims of the patents-in-suit in accordance with
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`long-established principles of claim construction—giving a claim term its ordinary meaning that
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`one of skill in the art, at the time of the invention and in light of the patent’s specification and
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`prosecution history, would have given it, except in two unusual circumstances: (1) where the
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`intrinsic record provides a special definition for the term; or (2) where the patentee disclaims a
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`portion of the term’s ordinary meaning. See, e.g., Phillips v. AWH Corp., 415 F.3d 1303, 1316–
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`17 (Fed. Cir. 2005). “[A]lthough the specification often describes very specific embodiments of
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`the invention, [the Federal Circuit has] repeatedly warned against confining the claims to those
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`embodiments.” Phillips, 415 F.3d at 1323 (citing Nazomi Communications, Inc. v. ARM
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`Holdings, PLC, 403 F.3d 1364, 1369 (Fed. Cir. 2005)). Limitations from the specification
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`should not be read into the claims unless the patentee “acted as his own lexicographer and
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`imbued the claim terms with a particular meaning or disavowed or disclaimed scope of coverage,
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`by using words or expressions of manifest exclusion or restriction.” E-Pass Techs., Inc. v. 3COM
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`Corp., 343 F.3d 1364, 1369 (Fed. Cir. 2003) (citations omitted).
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`Defendants seek to construe the claims in ways that have no basis in these or other
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`principles of construction. Because the Court is familiar with the law of claim construction as
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`well as the patents-in-suit, VirnetX will discuss specific claim construction principles only where
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`applicable to each dispute.
`VIRNETX’S OPENING CLAIM CONSTRUCTION BRIEF
`McKool 401908v2
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`PAGE 2 OF 29
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`Petitioner Apple Inc. - Ex. 1042, p. 2
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`III. LEVEL OF ORDINARY SKILL IN THE ART
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`Just as in the Microsoft litigation, VirnetX proposes that a person of ordinary skill in the
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`art would have a Master’s degree in computer science or computer engineering as well as two
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`years of experience in computer networking with some accompanying exposure to network
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`security. See Jones Decl. at ¶ 5. The Defendants have not disclosed a contention as to the level
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`of ordinary skill in the art.
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`IV. DISPUTED CLAIM CONSTRUCTIONS
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`A. Disputes Concerning Types of Communication Links
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`1. “virtual private network” [included in asserted claims of the ’135, ’180, and ’759 patents]
`VirnetX’s Proposed Construction
`Defendants’ Proposed Construction
`a network of computers which privately
`a network of computers which privately and
`communicate with each other by encrypting
`directly communicate with each other by
`traffic on insecure communication paths between
`encrypting
`traffic
`on
`insecure
`the computers
`communication paths between the computers
`where the communication is both secure and
`anonymous.
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`For the term “virtual private network,” or “VPN,” VirnetX proposes a construction
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`identical to the Court’s construction in the Microsoft case. See Ex. A (the Court’s claim
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`construction Memorandum in VirnetX Inc. v. Microsoft Corp., 6:07-cv-80) at 35. The
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`Defendants propose the same construction, but with two modifications: (i) the “where the
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`communication is both secure and anonymous” language; and (ii) the “directly” language. As
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`explained below, there is no legally justifiable basis for these modifications, and they would
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`impose erroneous, extraneous limitations into the claim.
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`“Anonymous.” The Defendants’ proposed language comes from the Court’s Microsoft
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`claim construction opinion, which states that the term “virtual private network” requires “both
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`data security and anonymity.” See Ex. A. at 9. Respectfully, VirnetX submits that the Court was
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`incorrect in requiring anonymity.
`VIRNETX’S OPENING CLAIM CONSTRUCTION BRIEF
`McKool 401908v2
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`PAGE 3 OF 29
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`Petitioner Apple Inc. - Ex. 1042, p. 3
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`The Court was correct that the ’135 patent discloses a way to achieve anonymity, i.e.,
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`“preventing[ing] an eavesdropper from discovering that terminal 100 is in communication with
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`terminal 110.” See Ex. A at 8 (citing the patent). But it does not follow that every claim in the
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`patent is directed toward achieving anonymity. Rather, only the dependent, “IP address
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`hopping” claims of the ’135 patent (e.g., claims 6, and 14-17) achieve the anonymity
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`contemplated by the patent. Specifically, the patent discusses how traffic analysis can defeat
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`anonymity by determining the identities of transmitters and receivers and how this is a problem
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`for various prior art communication schemes. See Background of the Invention, ’135::1:57-592
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`(“[P]roxy schemes are vulnerable to traffic analysis methods of determining identities of
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`transmitters and receivers.”) (emphasis added) see also ’135::2:46-47 (“[O]nion-routing . . . can
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`be defeated using traffic analysis.”) (emphasis added). The patent addresses the threat of
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`traffic analysis through its disclosed IP address hopping scheme. See ’135::5:13-20 (“IP address
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`changes [i.e., IP address hopping] made by TARP terminals and routers can be done at regular
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`intervals, at random intervals, or upon detection of ‘attacks.’ The variation of IP addresses
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`hinders traffic analysis that might reveal which computers are communicating, and also
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`provides a degree of immunity from attack.”) (emphasis added).
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`Separate and apart from the problem of traffic analysis vis-à-vis anonymity, the patent
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`also disclosed a new, better way to establish VPNs. See ’135::32:29-35 (“The following
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`describes various improvements and features that can be applied to the embodiments described
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`above. The improvements include: (1) . . . (2) a DNS proxy server that transparently creates a
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`virtual private network in response to a domain name inquiry[.]”). Claims 1, 10, and 13 claim
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`2 This brief uses the notation such as “’135::1:57-59” to refer to the lines 57 through 59 of
`column 1 of the ’135 patent.
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`VIRNETX’S OPENING CLAIM CONSTRUCTION BRIEF
`McKool 401908v2
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`PAGE 4 OF 29
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`Petitioner Apple Inc. - Ex. 1042, p. 4
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`are directed to this improvement, and these claims do not include the “IP address hopping”
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`limitation.3
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`In addition to revisiting the Court’s opinion regarding the requirement of anonymity, it is
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`important to revisit Microsoft’s arguments that supported it. Microsoft argued that anonymity is
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`a “primary purpose” of all VPNs. See Claim Construction Tr. from the Microsoft case, attached
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`as Ex. C, at 34:18-24.4 Microsoft’s lawyer then discussed an example VPN scheme—
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`encapsulation—to attempt to demonstrate that this is true. See Ex. C at 35:9-25. But contrary to
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`Microsoft’s lawyer’s representations, the purpose of encapsulation is not to hide the IP addresses
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`of the inner IP packet. See Jones Decl. at ¶ 6. Rather, the purpose of encapsulation is to enable
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`computers to communicate as though they were on the same, private network. See id. Namely,
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`in an encapsulation scheme, the outer IP packet transports the inner IP packet across the Internet
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`and to the private network. See id. The private network then extracts the inner IP packet and
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`routes it just as if the packet had originated within the network. In this way, the “anonymity” of
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`the inner packet’s IP addresses is merely a consequence of the true purpose of encapsulation—
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`enabling computers to communicate as if they were on the same private network. See id. This
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`3 The Court cited the specification’s discussion of IP addresses “still be hopped” for the
`proposition that “the modifications of the invention retain the anonymity feature.” See Ex. A at 9
`(citing ’135::23:20-25). The modification claimed in claims 1, 10, and 13, however, is discussed
`under the subheading “B. Use of a DNS Proxy to Transparently Create Virtual Private
`Networks,” which begins at col. 37, line 17. In that section, IP address hopping is described as
`merely “one embodiment.” See ’135::38:33-35 (“In one embodiment, gatekeeper 2603 creates
`“hopblocks” to be used by computer 2601 and secure target site 2604.”).
`4 The page numbers that VirnetX cites refer to the transcription page number and not the page
`numbers of the *.txt file. For clarity, 34:18-24 refers to the following argument: “Now, our view
`is that there are two primary purposes in a private network and VPN, as borne out by the
`specifications of the patents but also by the ordinary meaning to those skilled in the art. The first
`is data security, and the second is anonymity.”
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`VIRNETX’S OPENING CLAIM CONSTRUCTION BRIEF
`McKool 401908v2
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`PAGE 5 OF 29
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`Petitioner Apple Inc. - Ex. 1042, p. 5
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`view of VPNs is entirely consistent with the prosecution history of the ’135 patent. See Ex. B5 at
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`126 (explaining that Aventail does not teach a VPN because computers connected via the
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`Aventail system are not able to communicate with each other “as though they were on the same
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`network.”). Moreover, this view of VPNs is already supported by the Court’s construction for
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`this term in that a VPN allows computers to “privately communicate with each other.”
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`“Directly.” The Defendants propose that computers communicating in a VPN must
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`“directly” communicate with each other. Setting aside the ambiguity that this limitation would
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`create,7 this language should be rejected because there is no limiting language in the claims,
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`written description or prosecution history requiring that computers must communicate “directly”
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`in order to constitute a VPN. See Clearwater Sys. Corp. v. Evapco, Inc., 394 Fed. Appx. 699,
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`706 (Fed. Cir. 2010) (“There is no limiting language in the claims, written description, or
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`prosecution history requiring that the ‘power source’ power the entire apparatus. Accordingly,
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`the district court improperly imported an extraneous limitation into the claim.”).
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`5 Exhibit B contains selected excerpts to the prosecution history from the original examination
`and re-examination of the ’135 patent.
`6 For the Court’s convenience, VirnetX included page numbers for all of the prosecution history
`exhibits. The page numbers that VirnetX added are in blue font in the lower right-hand corner.
`When VirnetX cites to specific pages of these exhibits, VirnetX is referring to these blue page
`numbers.
`7 In the context of computer communications, the word “directly” is very ambiguous as most
`computer topologies include numerous network devices between two computers that are
`communicating. VirnetX did not argue that the term “directly” precluded the presence of
`intermediate network connections on the path between the client and the target that relay traffic.
`Rather, during reexamination, VirnetX explained that computers connected to the Aventail
`system did not communicate directly because “[a]ll communications between the client and
`target stop and start at the intermediate SOCKS server.” Ex. B at 14. If the Court were to accept
`the Defendants’ “directly” language in their proposed construction, VirnetX fully expects the
`Defendants to attempt to exploit this ambiguity in asserting non-infringement defenses based on
`intermediate network devices.
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`VIRNETX’S OPENING CLAIM CONSTRUCTION BRIEF
`McKool 401908v2
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`PAGE 6 OF 29
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`Petitioner Apple Inc. - Ex. 1042, p. 6
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`Presumably, the Defendants will rely on the prosecution history as allegedly supporting
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`constituting a disclaimer of scope, but the prosecution history gives no such support. As this
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`Court is well aware, not every description of a prior art reference is automatically a disclaimer of
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`scope. Rather, disclaimer is found when a patentee makes clear and unmistakable prosecution
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`arguments limiting the meaning of a claim term in order to overcome a rejection. See Omega
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`Eng’g, Inc. v. Raytek Corp., 334 F.3d 1314, 1324 (Fed. Cir. 2003) (“Where the patentee has
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`unequivocally disavowed a certain meaning to obtain his patent, the doctrine of prosecution
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`disclaimer attaches and narrows the ordinary meaning of the claim congruent with the scope of
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`the surrender.”). An exemplary case of prosecution history disclaimer is Rheox, Inc. v. Entact,
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`Inc., 276 F.3d 1319 (Fed. Cir. 2002). In that case, the patentee explicitly disclaimed compounds
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`of higher solubility to overcome an anticipation rejection; as a result, the patentee was barred
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`from later arguing that the claims should encompass such compounds. See id. at 1326.
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`In the re-examination of the ’135 patent, VirnetX provided three reasons why Aventail
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`did not teach a VPN. See Ex. B at 12-15. The three basic distinctions that VirnetX made over
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`Aventail were: first, that “Aventail has not been shown to demonstrate that computers connected
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`via the Aventail system are able to communicate with each other as though they were on the
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`same network,” see Ex. B at 12-13; second that “Aventail Connect’s fundamental operation is
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`incompatible with users transmitting data that is sensitive to network information,” see Ex. B at
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`13-14; and third, that “Aventail has not been shown to disclose a VPN because computers
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`connected according to Aventail do not communicate directly with each other,” see Ex. B at 14.8
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`As such, unlike the patentee in Rheox, VirnetX was not forced to overcome a reference by
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`8 VirnetX also disputed that the Aventail reference is prior art. See Ex. B at 9-11. After
`unsuccessfully searching to find evidence establishing Aventail as prior art, the examiner
`concluded that “Aventail cannot be relied upon as prior art to the ’135 patent.” See Ex. B. at 4-5.
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`VIRNETX’S OPENING CLAIM CONSTRUCTION BRIEF
`McKool 401908v2
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`PAGE 7 OF 29
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`Petitioner Apple Inc. - Ex. 1042, p. 7
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`disclaiming a certain scope of VPN taught by Aventail. Rather, VirnetX overcame Aventail on
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`the ground that Aventail did not teach a VPN at all.
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`Moreover, because VirnetX offered three distinctions over the Aventail reference, there
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`can be no “clear and unmistakable” disclaimer as to any one, isolated distinction. Momentus
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`Golf, Inc. v. Swingrite Golf Corp., 187 Fed. Appx. 981 (Fed. Cir. 2006) is instructive on this
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`point. In that case, a patentee distinguished its patented golf club swing aide over a prior art
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`reference on two grounds during prosecution. Namely the patentee argued to the USPTO that a
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`prior art golf club swing aide did not meet a claim term because the prior art golf club swing aide
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`was hollow and had a 10-25% club head weight. See id. at 984. The district court treated the
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`weight distinction—in isolation—as a disclaimer of scope, and the Federal Circuit found that to
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`be an erroneous application of prosecution history disclaimer. See id. The Federal Circuit
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`explained that the patentee’s statements did not meet the “clear and unmistakable” test because it
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`was unclear whether the patentee disclaimed hollow devices as well as devices with 10-25% club
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`head weight or alternatively whether the patentee merely disclaimed hollow devices with 10-
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`25% club head weights. See id. Similarly, the Defendants cannot meet the “clear and
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`unmistakable” test with respect to one of VirnetX’s three distinctions over the Aventail
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`reference.
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`For the foregoing reasons, VirnetX respectfully requests that the Court reconsider its
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`dicta concerning the meaning of “private” and in any event not require anonymity for the claim
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`term “virtual private network.”
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`VIRNETX’S OPENING CLAIM CONSTRUCTION BRIEF
`McKool 401908v2
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`
`
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`PAGE 8 OF 29
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`Petitioner Apple Inc. - Ex. 1042, p. 8
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`

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`Case 6:10-cv-00417-LED Document 173 Filed 11/04/11 Page 14 of 36 PageID #: 2666
`
`
`2. “virtual private link” [included in asserted claims of the ’135 patent]
`VirnetX’s Proposed Construction
`Defendants’ Proposed Construction
`a communication pathway
`that permits
`a communication link that permits computers to
`computers to privately communicate with
`privately communicate with each other by
`each other by encrypting traffic on insecure
`encrypting traffic on insecure communication
`communication paths between the computers
`paths between the computers
`and
`accomplishes
`data
`security
`and
`anonymity through the use of hop tables.
`
`VirnetX’s proposed construction for this term is adapted from the Court’s construction
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`for “virtual private network” in the Microsoft case. See Ex. A at 35. The Defendants’ proposed
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`construction is identical to VirnetX’s, but it includes the phrase “and accomplishes data security
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`and anonymity through the use of hop tables.” For the reasons stated in § IV.A.1, supra, the
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`Court should reject the Defendants’ attempt to impose the “anonymity” and “hop table”
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`limitations into this claim.
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`Further, the Defendants’ proposed construction would render the dependent claims
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`superfluous. Specifically, claims 14 through 17 of the ’135 patent add the additional
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`requirements that are directed to IP hopping. For example, claim 16 requires that the IP
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`addresses of a packet be compared against moving window of valid IP addresses. As such, there
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`is a strong presumption that the term “virtual private link” does not require anonymity or IP hop
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`tables. See, e.g., Zircon Corp. v. Stanley Black & Decker, Inc., 2011 U.S. App. LEXIS 20164
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`(Fed. Cir. Oct. 5, 2011) (“[T]he presumption arising from claim differentiation is a strong one
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`when the very limitation one seeks to import into an independent claim appears in a claim
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`dependent therefrom.”) (citing Liebel-Flarsheim Co. v. Medrad, Inc., 358 F.3d 898, 910 (Fed.
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`Cir. 2004)); but see Eon-Net LP v. Flagstar Bancorp, 653 F.3d 1314, at *18 (Fed. Cir. Jul. 29,
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`2011) (“[C]laim differentiation is a rule of thumb that does not trump the clear import of the
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`specification”) (citing Edwards Lifesciences, LLC v. Cook Inc., 582 F.3d 1322, 1331 (Fed. Cir.
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`2009)).
`
`VIRNETX’S OPENING CLAIM CONSTRUCTION BRIEF
`McKool 401908v2
`
`
`
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`PAGE 9 OF 29
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`Petitioner Apple Inc. - Ex. 1042, p. 9
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`

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`Case 6:10-cv-00417-LED Document 173 Filed 11/04/11 Page 15 of 36 PageID #: 2667
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`3. “secure communication link” [included in asserted claims of the ’504, ’211, and ’759
`patents]
`VirnetX’s Proposed Construction
`an encrypted communication link
`
`Defendants’ Proposed Construction
`virtual private network communication link.
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`As an initial matter, while the claim term “secure communication link” was at issue in the
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`Microsoft case, the Court found that no construction was necessary because the term was defined
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`in the claim as “virtual private network communication link.” See Ex. A at 25 (citing claims 1
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`and 16 of the ’759 patent). VirnetX does not dispute that “secure communication link” is limited
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`to “virtual private network communication link” for the claims of the ’759 patent for this reason.
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`(All claims in the ’759 patent define the term within the claims.) The claims in the ’504 and
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`’211 patents, however, do not define the “secure communication link” term in this way, and a
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`construction is therefore warranted.
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`VirnetX’s construction for this term is adapted directly from the specification. See
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`’504::1:55-569 (“Data security is usually tackled using some form of data encryption.”); see also
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`Ex. A at 25 (“Also, ‘communication’ and ‘link’ are common terms that jurors would understand
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`without a claim construction, and the patents do not assign any specialized meaning to these
`
`terms.”). This is the ordinary scope of “secure communication link” given in the patents, and the
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`Court should therefore adopt this construction.
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`Conversely, the Court should reject the Defendants’ construction for at least three
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`reasons. First, “[h]ad the inventors intended this limitation [to mean virtual private network
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`communication link], they could have