Case 6:10—cv—00417—LED Document 266
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`Filed 04/25/12 Page 1 of 31 PagelD#: 7521
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`IN THE UNITED STATES DISTRICT COURT
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`FOR THE EASTERN DISTRICT OF TEXAS
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`TYLER DIVISION
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`CASE NO. 6:]0~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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`§ §
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`VIRNETX INC.,
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`Plaintiff,
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`vs.
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`CISCO SYSTEMS, INC., et al.,
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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 US. 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 Markman hearing and agreed by the-parties, the Court ORDERS
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`that VirnetX Inc’s Motion to Compel from Apple a Complete Response to VirnetX’s Eighth
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`Common Interrogatory (Docket No. 179) is DENIED AS MOOT.
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`BACKGROUND
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`VimetX Inc. (“VimetX”) 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 cDefendants”). 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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`1
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`VIRNETX EXHIBIT 2004
`,,,,,APP19.“-Y:I9§¢X
`'Tnal IPR201500811
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`Page 1 of 31
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`VIRNETX EXHIBIT 2004
`Apple v. VirnetX
`Trial IPR2015-00811
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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 patents—in—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 VimeiX, Inc. v. Microsoft Corp, 2009 US. Dist.
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`LEXIS 65667, No. 6:07cv80 (ED. Tex. July 30, 2009) (“Microsofi”).
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`APPLICABLE LAW
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`“It is a ‘bedrock principle’ 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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`'
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`1312 (Fed. Cir. 2005) (en banc) (quoting Inflow/Pure Water Inc.
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`12. 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 All. Network Sewn, Inc. v. Covad
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`Commc’ns 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 1312713; Alloc, Inc. v. Ini’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
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`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]1aims 5must be read in view of the specification, of which they are a part.” Id.
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`(quoting Markman v. Wesrview 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 Viironics
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`Corp. v. Conceptmnic, Inc, 90 F.3d 1576, 1582 (Fed. Cir. 1996)); see also Teleflex, Inc. v.
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`Ficosa 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]lthough the specification may aid the court
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`in
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`interpreting the meaning of disputed claim language, particular embodiments and examples
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`appearing in the specification will not generally be read into the claims.” Comark Comma ’ns,
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`Inc. v. Harris Corp, 156 F.3d 1182, 1187 (Fed. Cir. 1998) (quoting Constant 12. Advanced
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`Moro-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 to supply the proper context for claim 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. Lifescan, 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). Technical 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
`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 also contend that some claims at issue are invalid for indefiniteness. A claim
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`is invalid under 35 U.S.C. § 112 ‘1] 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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`skilled in the art would not understand the scOpe of the claim when read in light of the
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`specification. Intellectual Prop. Dev., Inc. v. UAuCoiumbia Cabievision of Wesichesrer, 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 network
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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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`I 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 Microsoft. See
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`.Microsofi, 2009 US. Dist. LEXIS 65 667, at *8. Defendants seek to explicitly include the “secure
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`and anonymous” language that was implicitly included in the Court’s Microsoft construction. See
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`id. at >“l6 (“[T]he Court construes ‘Virtual private network1 as requiring both data security and
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`anonymity”). Just as in Microsofi, 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 Microsoft.
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`See id. at *14—17. For the same reasons stated in Microsofl‘, 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 VirnetX 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.1
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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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`.
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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 54'. Defendants argue that VimetX’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 Aventaii 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 Vimetxi
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`particularly-points one and three—reveal that the reason Aventaii 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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`VirnetX 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. Swingrz're Gm’fCorp, 187 Fed. App’x 981 (Fed. Cir. 2006), which involved a patent
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`directed to a golf club swing aide. During prosecution of the Momenrus 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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`1 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 God, 187 Fed. App’x at 984 (quoting prosecution
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`history). The district court held that this statement presented a clear disavowal of golf trainers
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`With 10525% club head weight because they would not meet the center of gravity requirement.
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`Id at 982. The Federal Circuit agreed that the district court’s interpretation was a fathomable
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`one. Id. at 983484. 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 10m25% 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. VimetX 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. 1.6,
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`at 5—6 (discussing the first reason); id. at 677 (discussing the second reason); id. at 7 (discussing
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`the third reason). In .Momemus 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, VirnctX 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. v.‘
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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 immunize 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 hep tables.”
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`VimetX’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 VirnetX‘s proposed construction of “virtual
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`private network” and “virtual priVate link.” Defendants contend that VimetX’s proposal
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`is
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`essentially “a communication link that permits computers to VPN.” Tr. of Marionan Hr”g 55,
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`Jan. 5, 2012. As a simplification, Defendants prepose “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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`the Markman hearing that they were not arguing “directly” requires a direct
`2 Defendants stipulated at
`electromechanical connection. See Tr. of Markman Hr’g 49750, Jan. 5, 2012. Rather, Defendants maintained that
`directly requires direct addressability. Thus, routers, firewalls, and simiiar 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. 44:1M5:35. This description discusses the use of hopping tables;
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`thus, Aastra
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`argues that this limitation should be imported into the claims.
`The Court rejects Aastra’s attempt to incorporate limitations of a preferred embodiment
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`into the claims. See Falana 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
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`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 interchangeabiy. 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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`. .”), 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 3l03.”), and id. col. 45332455 (“After a VPN has become inactive for a certain time
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`period (eg, one hour), the VPN can be automatically torn down by transport server 3102 or
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`signaling server 3101.”); see Nystmm v. Trex Co, Inc, 424 F.3d 1136, 1143 (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, VirnetX’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 construes “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 Morosofl 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. Mcrosofi, 2009 US. Dist. LEXIS 65667, at *43. For instance, claim 1 states: “the
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`secure communication link. being a virtual 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. li55756rVirnetX 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. VirnetX 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 link that is also a virtual private network communication iink. VimetX
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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. 6:61—62. Defendants further argue that the detailed
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`description of the invention also uses the terms “secure communication link” 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 US. 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 “181 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 all 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 Mcrosofi Corp. v. Mum-Tech Syn, 1110., 357 F.3d
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`1340, 1349 (Fed. Cir. 2004) (“[T]he prosecution history of one patent
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`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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`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 Servs. Corp. v. Vonage Holdings
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`Corp, 503 F.3d 1295, 1307 (Fed. Cir. 2007) (rejecting the argument that a disclaimer should not
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`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 ‘18l Patent, VirnetX distinguished the Aventail reference from the
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`“secure communication.
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`link” limitation using arguments nearly identical
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`to those discussed
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`Pagell 0f31 .
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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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`reexamination. Compare Docket No. 182 Attach. 16, at 5—7 (arguments regarding “virtual
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`private network” and Avcntail), 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, the parties agreed that it did not require construction
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`because the claim language itself defined the term as “being a virtual private network
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`. communication link.” “759 Patent col. 57:20722. However, the later—filed applications that issued
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`as the ‘504 and c211 Patents removed this defining language from the claims. Accordingly the
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`'
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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
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`of the Invention relates to a particular preferred embodiment and opens as follows:
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`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. 6:3642. 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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`6:434le (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 communication link is a virtual
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`Case 6:10—CV—00417—LED Document 266
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`Filed 04/25/12 Page 13 of 31 PagelD #: 7533
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`private network communication link.” Id. col. 6:61—63. The patentee is not acting as his owu
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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 Patent claims. Thus, secure
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`communication link shall be interpreted without this limitation in the ‘5 04 and “211 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. 5717,43 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. Velma, Inc, 438 F.3d 1374, 1380 (Fed.
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`Cir. 2006) (“‘[C]l.aim 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.” c504 Patent col.
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`115556 (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.”4
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`3 Claim 28 of the ‘211 Patent is similar.
`4 As the Court discussed earlier, the ‘759 Patent claims further limit the secure communication link recited therein.
`This construction does not contradict these provisions of the ‘75 9 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—00417—LED Document 266
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`Fited 04/25/12 Page 14 of 31 PagelD #: 7534
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`domain name service
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`VimetX proposes “a lookup 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 Mcrosofi. Defendants propose
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`to append “to the requester” to VimetX’s proposed construction.
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`VirnetX argues that Defendants’ proposal incorporates an extraneous limitation. Further,
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`VirnetX 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 7—8 (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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`I proxy, or both). VirnetX 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 .
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`, the server does not
`return the true 11’ 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. 37:63-38:2. Defendants argue that VimetX ignores the implicit meaning of the
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`Court’s Mcrosofi 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. 17 1] 8. Thus, VimetX argues, a domain
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`name request may cause an IP address to be returned “to the client, or to a DNS proxy .
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`.
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`.
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`, or
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`both.” Id. VimetX’s expert is effectively describing a scenario detailed in the “135 Patent and
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`cited above by VirnetX. This scenario is further described in detail
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`in the specification and
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`depicted in Figure 26. See “135 Patent col. 3821342 (describing the operation of the system
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`Case 6:10—cv—00417—LED Document 266
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`depicted in Figure 26). VirnetX 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 non—secure 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
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`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. 3813642. The DNS Proxy 2610, operating as an internal. component of the modified
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`DNS server 2602, returns an address to the requester, the client computer 2601. Thus, viewing
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`the modified DNS server 2602 as a black box, it remrned 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 I]?
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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-OO417—LED Document 266
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`Filed 04/25/12 Page 16 of 31 PagelD #: 7536
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`domain name
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`VimetX proposes the same construction adopted by the Court in Mcrosofi: “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 1? address.” In Mcrosofi, 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. See M'crosofi, 2009 US. Dist. LEXIS 65667, at *24m25. For
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`the same reasons stated in Mcmsofi,
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`the Court construes “domain name” as “a name
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`corresponding to an lP 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