Case 6:10-cv-00417—LED Document 266
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`Filed 04/2512 Page 1 of 31 PagelD #: 7521
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`IN THE UNITED STATES DISTRICT COURT
`FOR THE EASTERN DISTRICT OF TEXAS
`TYLER DIVISION
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`CASE NO. 6:10—CV-417
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`§
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`§ §
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`§ §
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`§
`§
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`§ §
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`§ §
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`VIRNETX INC.,
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`Plaintiff,
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`vs.
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`CISCO SYSTEMS, INC., et 31.,
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`Defendants.
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`MEMORANDUM OPINION AND ORDER
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`This Memorandum Opinion construes the disputed claim terms in U.S. Patent Nos.
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`6,502,135 (“the “135 Patent”), 6,839,759 (“the ‘759 Patent”), 7,188,180 (“the ‘180 Patent”),
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`7,418,504 (“the ‘504 Patent”), 7,490,151 (“the ‘151 Patent”), and 7,921,211 (“the “211 Patent”).
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`Further, as stated at the Marianna hearing and agreed by the parties, the Court ORDERS
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`that VimetX Inc.’s Motion to Compel from Apple a Complete Response to VimetX’s Eighth
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`Common lnterrogatory (Docket No. 179) is DENIED AS MOOT.
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`BACKGROUND
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`VirnetX Inc. (“VirnetX”) asserts all six patents—in—suit against Aastra Technologies Ltd.;
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`Aastra USA, Inc; Apple Inc; Cisco Systems, Inc; NEC Corporation; and NEC Corporation of
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`America (collectively “Dcfendants”). The ‘135 Patent discloses a method of transparently
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`creating a Virtual private network (“VPN”) between a client computer and a target computer. The
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`‘759 Patent discloses a method for establishing a VPN without a user entering user identification
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`information. The ‘180 Patent discloses a method of establishing a secure communication link
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`between two computers. The ‘504 and ‘211 Patents disclose a secure domain name service. The
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`.VIRNETX EXHIBIT 2004
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`Apple V. VirnetX
`Trial IPR2015-00812
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`‘151 Patent discloses a domain name service capable of handling both standard and non-standard
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`domain name service queries.
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`The patentsvin—suit are all related; Application No. 09/504,783 (“the ‘783 Application”) is
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`an ancestor application for every patent—in-suit. The ‘135 Patent issued on December 31, 2002,
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`from the ‘783 Application. The ‘151 Patent issued from a division of the ‘783 Application. The
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`‘180 Patent issued from a division of a continuation-in—part of the “783 Application. Both the
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`‘759 and ‘504 Patents issued from a continuation of a continuation—in-part of the ‘783
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`Application. Finally, the ‘211 Patent is a continuation of the application that resulted in the ‘504'
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`patent.
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`The Court has already construed many of the terms at issue in a previous case that
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`involved the ‘135, ‘759, and ‘180 Patents. See VirnetX, Inc. v. Microsofi Corp, 2009 US. Dist.
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`LEXIS 65667, No. 6:07cv80 (ED. Tex. July 30, 2009) (“Microsoft”).
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`APPLICABLE LAW
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`“It is a ‘bedrock principle1 of patent law that ‘the claims of a patent define the invention
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`to which the patentee is entitled the right to exclude.” Phillips v. AWH Corp, 415 F.3d 1303,
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`1312 (Fed. Cir. 2005) (en banc) (quoting Innova/Pure Water Inc. v. Safari Water Filtration Syn,
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`Inc, 381 F.3d 1111, 1115 (Fed. Cir. 2004)). In claim construction, courts examine the patent’s
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`intrinsic evidence to define the patented invention’s scope. See id; CR. Bard, Inc. v. US.
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`Surgical Corp, 388 F.3d 858, 861 (Fed. Cir. 2004); Bell At]. Network Saws, Inc. v. Covad
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`Commons Group, Inc, 262 F.3d 1258, 1267 (Fed. Cir. 2001). This intrinsic evidence includes
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`the claims themselves, the specification, and the prosecution history. See Phillips, 415 F.3d at
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`1314; CR. Bard, Inc, 388 F .3d at 861. Courts give claim terms their ordinary and accustomed
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`meaning as understood by one of ordinary skill in the art at the time of the invention in the
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`context of the entire patent. Phillips, 415 F.3d at 1312—13; Alice, Inc. v. Im’l Trade Comm’n,
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`342 F.3d 1361, 1368 (Fed. Cir. 2003).
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`The claims themselves provide substantial guidance in determining the meaning of
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`particular claim terms. Phillips, 415 F.3d at 1314. First, a term’s context in the asserted claim
`can be very instructive. Id. Other asserted or unasserted claims can also aid in determining the
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`claim’s meaning because claim terms are typically used consistently throughout the patent.- Id.
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`Differences among the claim terms can also assist in understanding a term’s meaning. Id. For
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`example, when a dependent claim adds a limitation to an independent claim, it is presumed that
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`the independent claim does not include the limitation. Id. at 1314—15.
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`“[C]laims “must be read in view of the specification, of which they are a part.” Id.
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`(quoting Markman v. Westview Instruments. Inc, 52 F.3d 967, 979 (Fed. Cir. 1995) (en banc)).
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`“[T]he specification “is always highly relevant to the claim construction analysis. Usually, it is
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`dispositive; it is the single best guide to the meaning of a disputed term.” Id. (quoting Vitronics
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`Corp. v. Conceptronic, Inc, 90 F.3d 1576, 1582 (Fed. Cir. 1996)); see also Teleflex, Inc. v.
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`Ficcsa N. Am. Corp, 299 F.3d 1313, 1325 (Fed. Cir. 2002). This is true because a patentee may
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`define his own terms, give a claim term a different meaning than the term would otherwise
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`possess, or disclaim or disavow the claim scope. Phillips, 415 F.3d at 1316. In these situations,
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`the inventor’s lexicography governs. Id. Also, the specification may resolve ambiguous claim
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`terms “where the ordinary and accustomed meaning of the words used in the claims lack
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`sufficient clarity to permit the scope of the claim to be ascertained from the words alone.”
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`Teleflex, Inc, 299 F.3d at 1325. But, “‘[a]1th0ugh the specification may aid the court in
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`interpreting the meaning of disputed claim language, particular embodiments and examples
`”3
`appearing in the specification will not generally be read into the claims. Comark Commc’ns,
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`Inc.
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`12. Harris Corp, 156 F.3d 1182, 1187 (Fed. Cir. 1998) (quoting Constant v. Advanced
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`Micro-Devices, Inc, 848 F.2d 1560, 1571 (Fed. Cir. 1988)); see also Phillips, 415 F.3d at 1323.
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`The prosecution history is another tool
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`to supply the proper context for c1ai1n construction
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`because a patent applicant may also define a term in prosecuting the patent. Home Diagnostics,
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`Inc, v. Liflascan, Inc, 381 F.3d 1352, 1356 (Fed. Cir. 2004) (“As in the case of the specification,
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`a patent applicant may define a term in prosecuting a patent”).-
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`Although extrinsic evidence can be useful, it is “‘less significant than the intrinsic record
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`in determining the legally operative meaning of claim language.” Phillips, 415 F.3d at 1317
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`(quoting CR. Bard, Inc, 388 F.3d at 862). Technicai dictionaries and treatises may help a court
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`understand the underlying technology and the manner in which one skilled in the art might use
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`claim terms, but technical dictionaries and treatises may provide definitions that are too broad or
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`may not be indicative of how the term is used in the patent. Id. at 1318. Similarly, expert
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`testimony may aid a court in understanding the underlying technology and determining the
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`
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`particular meaning of a term in the pertinent field, but an expert’s conclusory, unsupported
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`assertions as to a term’s definition is entirely unhelpful to a court. Id. Generally, extrinsic
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`evidence is “less reliable than the patent and its prosecution history in determining how to read
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`claim terms.” Id.
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`Defendants aiso contend that some claims at issue are invalid for indefiniteness. A claim
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`is invalid under 35 U.S.C. § 112 11 2 if it fails to particularly point out and distinctly claim the
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`subject matter that the applicant regards as the invention. The party seeking to invalidate a claim
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`under 35 U.S.C. § 112 11 2 as indefinite must Show by clear and convincing evidence that one
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`skilied in the art would not understand the scope of the claim when read in light of the
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`specification. Intellectual Prop. Dem, Inc. v. Uzi—Columbia Cablevision of Westchester, Inc, 336
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`F.3d 1308, 1319 (Fed. Cir. 2003).
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`LEVEL OF ORDINARY SKILL IN THE ART
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`The parties agree that a person of ordinary skill in the art would have a master’s degree in
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`computer science or computer engineering and approximately two years of experience in
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`computer networking and computer network security.
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`CLAIM TERMS
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`virtual private [1 etwork
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`VirnetX proposes “a network of computers which privately communicate with each other
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`by encrypting traffic on insecure communication paths between the computers.” Defendants
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`propose the following emphasized additions: “a network of computers which privately and
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`directly communicate with each other by encrypting traffic on insecure communication paths
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`between the computers where the communication is both secure and anonymous.”
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`secure and anonymous
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`VirnetX proposes the same construction adopted by this Court
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`in Microsofl. See
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`Microsofi, 2009 US. Dist. LEXIS 65667, at *8. Defendants seek to explicitly include the “secure
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`and anonymous” language that was implicitly included in the Court’s Microsofl construction. See
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`id. at *16 (“[T]he Court construes “virtual private network” as requiring both data security and
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`anonymity”). Just as in Microsoft, the parties here dispute whether a virtual private network
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`requires anonymity, and the Court hereby incorporates by reference its reasoning in Mcrosofi.
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`See I'd. at *14717. For the same reasons stated in Merosoft, the Court finds that a virtual private
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`network requires both data security and anonymity. For clarity, this language is now explicitly
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`included in the Court’s construction of “virtual private network.”
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`directly
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`Defendants propose that communication within a virtual private network is “direct” based
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`on. arguments that VimetX made to the United States Patent and Trademark Office (“PTO”) to
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`overcome rejections based on the Aventail reference during reexamination of the ‘135 Patent]
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`VirnetX provided three reasons that Aventail did not disclose a virtual private network:
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`First, Aventail has not been shown to demonstrate that computers connected via
`the Aventail system are able to communicate with each other as though they were
`on the same network. .
`.
`.
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`Second, according to Aventail, Aventail Connect’s fundamental operation
`incompatible with users transmitting data that
`is
`sensitive to network
`is
`information .
`.
`.
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`Third, Aventail has not been shown to disclose a VPN because computers
`connected according to Aventail do not communicate directly with each other.
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`Docket No. 182 Attach. 16, at 577. Defendants argue that VirnetX’s third distinction warrants a
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`finding that communication over a virtual private network must be direct.
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`VimetX argues that its statements during reexamination are not a clear disavowal of
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`claim scope. Rather, VirnetX contends that it “overcame Aventail on the ground that Aventail
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`did not teach a VPN at all.” Docket No. 173, at 8. However, the statements made by VimetXW
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`particularly points one and threemreveal that the reason Aventail did not disclose a VPN was
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`because it did not permit direct communication between the source and target computers.
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`VimetX further argues that it did not clearly disavow claim scope regarding any one of
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`the three distinctions between Aventail and a VPN. For support, VirnetX relies on Momentus
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`Golf, Inc. v. Swingrite GolfCorp, 187 Fed. App”): 981 (Fed. Cir. 2006), which involved a patent
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`directed to a golf club swing aide. During prosecution of the Momentus Golf patent,
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`the
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`applicants stated: “A hollow device having 10—25% club head weight cannot'meet
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`the
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`' The Aventail reference involved a means of secure communication between two clients via an intermediary
`SOCKS server.
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`requirement in applicant’s claims that the center of gravity of the trainer be substantially at the
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`center of a solid round stock.” Momenrus Golf. 187 Fed. App’x at 984 (quoting prosecuti0n
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`history). The district court held that this statement presented a clear disavowal of golf trainers
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`with 10~25% club head weight because they would not meet the center of gravity requirement.
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`1d. at 982. The Federal Circuit agreed that the district court’s interpretation was a fathomable
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`one. Id. at 983w84. However, it reversed the district court because another interpretation was also
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`reasonable and still supported the applicant’s distinguishing arguments—that the statement only
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`clearly disavowed hollow clubs with 10—25% club head weight. Id. at 984 (emphasis added). The
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`Federal Circuit held that the statement could reasonably be interpreted to disavow (1) clubs with '
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`10—25% club head weight or (2) hollow clubs with 10725% club head weight. in light of the
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`competing interpretations, the Federal Circuit determined that there was only a disclaimer of the
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`more narrow interpretation.
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`The instant case does not present such an ambiguous statement. VirnetX stated that
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`“Aventail has not been shown to disclose the VPN .
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`.
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`. for at least three reasons.” Docket No. 182
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`Attach. 16, at 5. VirnetX then proceeded to independently present and discuss each of the three
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`distinct reasons that Aventail did not disclose the claimed VPN. See Docket No. 182 Attach. 16,
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`at 5—6 (discussing the first reason); id. at 6—7 (discussing the second reason); id. at 7 (discussing
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`the third reason). In Momenius Golf, the applicant combined two potential distinctions in a single
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`sentence, creating ambiguity as to whether the distinctions were independent or intertwined.
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`Here, VirnetX expressly stated that there were three bases for distinction. Each of these reasons,
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`alone, served to distinguish the claimed VPN from the Aventail reference. See Andersen Corp. 12.
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`Fiber Composites, LLC, 474 F.3d 1361, 1374 (Fed. Cir. 2007') (“An applicant’s invocation of
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`multiple grounds for distinguishing a prior art reference does not imrnunize each of them from
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`being used to construe the claim language”). Accordingly, the Court finds that the claimed
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`“virtual private network” requires direct communication between member computers.2
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`'The Court construes “virtual private network” as “a network of computers which
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`privately and directly communicate with each other by encrypting traffic on insecure paths
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`between the computers where the communication is both secure and anonymous.”
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`virtual private link
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`VimetX proposes
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`“a
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`communication link that permits
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`computers
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`to privately
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`communicate with each other by encrypting traffic on insecure communication paths between the
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`computers.” Defendants, except the two Aastra entities, propose “a link in a virtual private
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`network.” The Aastra entities propose “a link in a virtual private network that accomplishes data
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`security and anonymity through the use of hop tables.”
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`VirnetX’s proposed construction closely tracks its proposal for “virtual private network,”
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`replacing “a network of computers which” with “a communication link that permits computers
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`to.” “Network of computers” implies that
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`the computers are linked together;
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`likewise a
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`“communication link that permits computers [to communicate]” implies a computer network.
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`Defendants also note the similarity between VimetX’s proposed construction of “virtual
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`private network” and “virtual private link.” Defendants contend that VirnetX’s proposal
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`is
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`essentially “a communication link that permits computers to VPN.” Tr. of Markman Hr” g 55,
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`Jan. 5, 2012. As a simplification, Defendants propose “a link in a virtual private network.”
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`The Aastra entities argue that a virtual private link should be limited to virtual private
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`network links that use hop tables to achieve data security and anonymity. An embodiment of
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`they were not arguing “directly” requires a direct
`the Marlmian hearing that
`stipulated at
`2 Defendants
`electromechanical connection. See Tr. of Markman Hr’g 49—50, Jan. 5, 2012. Rather, Defendants maintained that
`directly requires direct addressability. Thus, routers, firewalls, and similar servers that participate in typical network
`communication. do not impede ”direct” communication between a client and target computer.
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`claim 13 of the ‘135 Patent, which contains the term “virtual private link,” is depicted in Figure
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`31. A detailed description of this embodiment is also provided in the specification. See ‘135
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`Patent cols. 44:14—45:35. This description discusses the use of hopping tables; thus, Aastra
`argues that this-limitation should be imported into the claims.
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`The Court rejects Aastra’s attempt to incorporate limitations of a preferred embodiment
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`into the claims. See Fatal/to v. Kent State Univ., 669 F.3d 1349, 1355 (Fed. Cir. 2012) (cautioning
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`against importing limitations from a preferred embodiment into the claims). The specification
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`notes that the use of hopping is one option for accomplishing the data security and anonymity
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`features. See ‘135 Patent col. 45 :10—13 (“‘Next, signaling server 3101 issues a request to
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`transport server 3102 to allocate a hopping table (or hopping algorithm or other regime) for the
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`purpose of creating a VPN with client 3103” (emphasis added)). Thus, the applicants envisioned
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`alternate methods of implementing data security and anonymity beyond hopping tables, and
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`importing the hopping limitation into the claims is inappropriate.
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`The patent specification, in the detailed description of Figure 31, uses the term virtual
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`private network and virtual private link interchangeably. Compare id. col. 44:37—40 (“When a
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`packet is received from a known user, the signaling server activates a virtual private link (VPL)
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`between the user and the transport server .
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`.
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`. 3’), with id. col. 45:10—13 (noting that the signaling
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`server requests the transport server to create a hopping table for the purpose of “creating a VPN
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`with client 3103.”), and id, col. 45:32—35 (“After a VPN has become inactive for a certain time
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`period (e.g., one hour), the VPN can be automatically torn down by transport server 3102 or
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`signaling server 3101.”); see Nysrrom v. Trex Co, Inc., 424 F.3d 1136, ll43 (Fed. Cir. 2005)
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`(“Different terms or phrases in separate claims may be construed to cover the same subject
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`matter where the written description and prosecution history indicate that such a reading of the
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`terms or phrases is proper”). Finally, VimetX’s and Defendants” proposed constructions of
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`virtual private link are very similar to their proposed constructions for virtual private network.
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`Accordingly,
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`the Court construcs “virtual private link” as “a virtual private network as
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`previously defined.”
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`secure communication link
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`VirnetX proposes “an encrypted communication link.” Defendants propose “virtual
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`private network communication link.” The parties in Microsofi agreed that this term, as used in
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`the ‘759 Patent, did not require construction because the claims themselves provide a definition
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`of the term. Microsoft, 2009 US. Dist. LEXIS 65667, at *43. For instance, claim 1 states: “the
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`secure communication link being a virmal private network communication link over the
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`computer network.” ‘759 Patent col. 57:20~22. Here, the parties also agree that, as to the ‘759
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`Patent, the term means “virtual private network communication link.” However, the claims of the
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`‘504 and ‘211 Patents use this term without further defining it. Thus, the parties dispute the
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`construction of the term as used in the ‘504 and ‘211 Patents.
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`VirnetX contends that “secure” means the link uses some form of data encryption,
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`highlighting the following passage from the ‘504 Patent specification: “Data security is usually
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`tackled using some form of data encryption.” ‘504 Patent col. 1:55—56. VimetX argues that the
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`inventors would have used the term “virtual private network communication link” had it desired
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`to limit “secure communication link” to that interpretation. VimetX further argues Defendants’
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`proposal improperly imports a limitation from the preferred embodiment, which discloses a
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`secure communication Eink that is also a virtual private network communication link. VirnctX
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`states that “Defendants fail to explain why a secure communication link must always be a virtual
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`private netWOrk communication link for all possible embodiments of the claims.” Docket No.
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`192, at 4. Finally, VirnetX argues that
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`it did not narrow the interpretation of “secure
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`communication link” during the prosecution of the ‘504 and ‘211 Patents.
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`Defendants argue that secure communication link is defined in the Summary of the
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`Invention: “The secure communication link is a virtual private network communication link over
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`the computer network.” ‘504 Patent col. 6:61762. Defendants further argue that the detailed
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`description of the invention also uses the terms “secure communication 1i
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`” and “virtual private
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`network communication link” synonymously. Defendants also highlight VirnetX’s arguments
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`regarding “secure communication link” while prosecuting U.S. Patent No. 8,051,181 (“the ‘181
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`patent”), a related patent that is not at issue in the instant case.
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`The ‘18] Patent is related to the patents-in-suit; it is a division of a continuation—in—part
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`of the ‘783 Application that serves as an ancestor application for ali of the patents-in-suit. The
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`Federal Circuit has held that arguments to the PTO regarding one patent application are
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`applicable to related patent applications. See Microsoft Corp. v. Mufti-Tech Syn, Inc, 357 F.3d
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`1340, 1349 (Fed. Cir. 2004) (“[T]he prosecution history of one patent
`
`is relevant
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`to an
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`understanding of the scope of a common term in a second patent stemming from the same parent
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`
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`application”). The Federal Circuit has also held that arguments regarding a later filed application
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`may be applicable to a previously filed application. See Verizon Saws. Corp. v. Vonage Holdings
`
`Corp, 503 F.3d 1295, 1307 (Fed. Cir. 2007) (rejecting the argument that a disclaimer should not
`
`apply because it occurred after the patent under consideration had issued). Here, the ‘181 Patent
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`issued after all of the patents-in—suit. Its application was filed later than the applications for the
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`patents—in—suit except for the ‘211 Patent, which was filed approximately six months earlier.
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`When prosecuting the ‘181 Patent, VirnetX distinguished the Aventail reference from the
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`“secure communication link” limitation using arguments nearly identical to those discussed
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`earlier regarding Aventail and the “virtual private network” term. VimetX argued that Aventail
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`failed to disclose a “secure communication link” for the same three reasons asserted in the ‘135
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`
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`reexamination. Compare Docket No. 182 Attach. 16, at 5—7 (arguments regarding “virtual
`
`private network” and Aventail), with Docket No. 202 Attach. l, at 6—8 (arguments regarding
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`“secure communication link” and Aventail). Therefore, for the same reasons stated earlier
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`regarding “virtual private network,” a “secure communication link” also requires direct
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`communication between its nodes.
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`“Secure communication link” was originally used in the claims of the ‘759 Patent, which
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`was also at issue in Microsoft. There,
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`the parties agreed that it did not require construction
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`because the claim tanguage itself defined the term as “being a virtual private network
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`communication link.” “759 Patent col. 57:20—22. However, the later-filed applications that issued
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`as the “504 and ‘211 Patents removed this defining language from the claims. Accordingly the
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`term is not so limited in the ‘504 and ‘211 Patents as in the “759 Patent.
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`Defendants argue that the Summary of the Invention defined a secure communication
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`link as a- virtual private network communication link. However, this discussion in the Summary
`
`of the Invention relates to a particular preferred embodiment and opens as follows:
`
`invention, a user can conveniently
`According to one aspect of the present
`establish a VPN using a “one-click” .
`.
`. technique withOut being required to enter
`[information] for establishing a VPN. The advantages of the present invention are
`provided by a method for establishing a secure communication link .
`.
`.
`.
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`‘504 Patent col. 613642. Thus, the advantage of being able to seamlessly establish a one-click
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`VPN is provided by “a method for establishing a secure communication link.” The description
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`continues by describing the details of an embodiment that realizes this advantage. See id. cols.
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`6:434:10 (describing the one-click embodiment). It is within this description of the preferred
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`embodiment that the specification acknowledges that the “secure cornmunication link is a virtual
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`private network communication link.” 1d. col. 6:61763. The patentee is not acting as his own
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`lexicographer here; rather, he is describing a preferred embodiment. The claims and specification
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`of the ‘504 and ‘211 Patents reveal that the patentee made a conscious decision to remove the
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`virtual private network limitation originally present in the ‘759 Patth claims. Thus, secure
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`communication link shall be interpreted without this limitation in the ‘504 and ‘21]. Patents.
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`VimetX proposes that a secure communication link is an encrypted link. However, claim
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`28 of the ‘504 Patent3 covers “[t]he system of claim 1, wherein the secure communication link
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`uses encryption.” ‘504 Patent col. 57117718. VirnetX’s proposal seeks to import a limitation
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`from dependent claim 28 into independent claim 1, and this violates the doctrine of claim
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`differentiation. See Curtiss- Wright Flow Control Corp. V. Velon, Inc, 438 F.3d 1374, 1380 (Fed.
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`Cir. 2006) (“‘[C]laim differentiation’ refers to the presumption that an independent claim should
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`not be construed as requiring a limitation added by a dependent claim.”). The specification notes
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`that “[d]ata security is usually tackled using some form of data encryption.” ‘504 Patent col.
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`1:55w56 (emphasis added). Therefore, encryption is not the only means of addressing data
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`security. Accordingly, a secure communication link is one that provides data security, which
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`includes encryption.
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`The Court construes “secure communication link” as “a direct communication link that
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`provides data security?”1
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`3 Claim 28 ofthe ‘21] Patent is similar.
`4 As the Court discussed earlier, the “759 Patent ciaims further limit the secure communication link recited therein.
`This construction does not contradict these provisions of the ‘759 claims, which limit the secure communication link
`there to a virtual private network communication link. Thus, as a practical matter, the “secure communication link”
`recited in the ‘759 Patent claims is a “virtual private network communication link.”
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`Case 6:10-cv—004‘IT—LED Document 266
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`Filed 04/25/12 Page 14 of31 PagelD #: 7534
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`domain name service
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`VirnetX preposes “a lockup service that returns an IP address for a requested domain
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`name,” adopting the Court’s previous construction of this term in Microsofi. Defendants propose
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`to append “to the requester” to VirnetX’s proposed construction.
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`VirnetX argues that Defendants’ proposal incorporates an extraneous limitation. Further,
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`VimetX provides an expert declaration stating that one of skill in the art, after reading the
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`specification, would understand that a domain name service does not necessarily return the
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`requested IP address to the requester. See Docket No. 173 Attach. 17 W 778 (stating that in the
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`context of a DNS proxy, the IP address may be returned to the original requesting client, the
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`proxy, or both). VimetX also argues that the specification envisions a domain name service that
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`does not always return an address to the requester. For instance, the specification states:
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`According to certain aspects of the invention, a specialized DNS server traps DNS
`requests and, if the request is from a special type of user .
`.
`. , the server does not
`return the true IP address of the target node, but instead automatically sets up a
`virtual private network between the target node and the user.
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`‘135 Patent cols. 37:63—38z2. Defendants argue that VirnetX ignores the implicit meaning of the
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`Court’s Microsofi construction by arguing that a domain name service does not necessarily
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`return the requested IP address to the requester.
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`VirnetX’s expert explains that “in one mode, the domain name request can be received by
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`a DNS proxy (or DNS proxy module), which, in turn, may forward the request to a DNS function
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`that can return an IP address.” Docket No. 173 Attach. l7 1] 8. Thus, VirnetX argues, a domain
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`name request may cause an IP address to be returned “to the ciient, or to a DNS proxy .
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`.
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`.
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`, or
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`both.” Id. VirnetX’s expert is effectively describing a scenario detailed in the ‘135 Patent and
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`cited above by VimetX. This scenario is further described in detail in the specification and
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`depicted in Figure 26. See ‘135 Patent col. 38:13—42 (describing the operation of the system
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`Case 6:10—cv—00417-LED Document 266
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`Filed 04/25112 Page 15 of 31 PagelD #: 7535
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`depicted in Figure 26). VimetX asserts that Defendants” proposed construction precludes this
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`preferred embodiment.
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`Contrary to VirnetX’s argument, Defendants” proposed limitation does not preclude a
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`preferred embodiment. The “specialized” or “modified” DNS server
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`referenced in the
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`specification is shown as 2602 in Figure 26. This modified DNS server contains a DNS proxy
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`function and a standard DNS server function. Requests for nonusecure sites are passed through to
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`the DNS server, and an IP address is returned to the requesting client. In this case, two separate
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`domain name requests are effectively being made: (1) between the client computer 2601 and the
`modified DNS server 2602; and (2) between the DNS Proxy 2610 and the DNS Server 2609. If
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`the original client request is for a secure site, then the DNS Proxy 2610 establishes a VPN
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`connection between the client and the secure site. The specification explains the final stages of
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`this process:
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`Thereafter, DNS proxy 2610 returns to user computer 2601 the resolved address
`passed to it by the gatekeeper (this address could be different from the actual
`target computer) 2604, preferably using a secure administrative VPN. The address
`that is returned need not be the actual address of the destination computer.
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`Id. col. 38:3642. The DNS Proxy 2610, operating as an internal component of the modified
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`DNS server 2602, returns an address to the requestor, the client computer 2601. Thus, viewing
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`the modified DNS server 2602 as a black box, it returned an address to the requesting client
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`computer.
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`For these reasons, the Court finds that a domain name service inherently returns the LP
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`address for a requested domain name to the requesting party. The Court construes “domain name
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`service” as “a lookup service that returns an IP address for a requested domain name to the
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`requester.”
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`Case 6:10—cv-00417-LED Document 266
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`Filed 04l25/12 Page 16 of31 PagelD #: 7536
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`domain name
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`VirnetX proposes the same construction adopted by the Court in Microsoft: “a name
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`corresponding to an IP address.” Defendants propose “a hierarchical sequence of words in
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`decreasing order of specificity that corresponds to a numerical IP address.” 111 Microsoft, the
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`Court addressed Defendants’ argument that a domain name is necessarily hierarchical in nature;
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`that analysis is incorporated herein. Sec Microsofi, 2009 U.S. Dist. LEXIS 65667, at *24m25. For
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`the same reasons stated in Microsoft,
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`the Court construes “domain name” as “a name
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`corresponding to an IP address.”
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`DNS proxy server
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`VirnetX proposes “a computer or program that responds to a domain name inquiry in
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`place of a DNS.” Defendants propose “a computer or program that responds to a domain name
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`inquiry in place of a DNS, and prevents destination servers from determining the identity of the
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`entity sending the domain name inquiry.” VimetX‘s proposal and the first portion of Defendants’
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`proposal reflect the construction adopted by this Court in Microsofi. Id. at *39. Here, the dispute
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`is whether a DNS proxy server “prev