Microsoft Corp v. VirnetX Inc

1. Case Identification

• Case #: IPR2014-00401
• Patent #: 7,188,180
• Filed: January 31, 2014
• Petitioner(s): Microsoft Corporation
• Patent Owner(s): VirnetX Inc.
• Challenged Claims: 1, 4, 6, 10, 12-15, 17, 20, 22, 26, 28-31, 33, 35, and 37

2. Patent Overview

• Title: METHOD FOR ESTABLISHING SECURE COMMUNICATION LINK BETWEEN COMPUTERS OF VIRTUAL PRIVATE NETWORK
• Brief Description: The ’180 patent discloses methods for establishing a secure communication link to a computer within a private network. The method involves a client computer using a non-standard "secure domain name," querying a special "secure domain name service" (SDNS) to resolve that name into a network address, and then using that address to initiate a secure connection via a virtual private network (VPN) communication link.

3. Grounds for Unpatentability

Ground 1: Anticipation over Provino - Claims 1, 10, 12-15, 17, 26, 28-31, and 33 are anticipated by Provino under 35 U.S.C. §102.

• Prior Art Relied Upon: Provino (Patent 6,557,037).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Provino discloses every limitation of the challenged independent claims. Provino describes a two-phase process for an external client device to securely communicate with a server inside a VPN. First, the client establishes a secure tunnel to the VPN's firewall. Second, when the user provides a "human-readable Internet address" for an internal server (the claimed "secure domain name"), the client device first queries a conventional external nameserver, which fails. The device then sends a query through the secure tunnel to a dedicated nameserver inside the VPN (the claimed "secure domain name service"). This internal nameserver resolves the address and returns the server's IP address (the "secure computer network address"). The client then uses this IP address to send an access request to the server through the secure tunnel, which constitutes the claimed "virtual private network communication link."

Ground 2: Obviousness over Provino, Guillen, and Kosiur - Claims 4, 6, 20, 22, 35, and 37 are obvious over Provino in view of Guillen and Kosiur under 35 U.S.C. §103.

• Prior Art Relied Upon: Provino (Patent 6,557,037), Guillen (a 1993 conference paper on QoS routing), and Kosiur (a 1998 book on managing VPNs).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground addressed dependent claims requiring "provisioning information" or a "predetermined level of service." Petitioner asserted that Provino’s VPN system lacks an explicit disclosure of providing Quality of Service (QoS) information. Guillen was introduced for its teaching of using directory services, like DNS, to store and provide QoS parameters to clients during address resolution, enabling applications to request a specific level of service. Kosiur was cited to establish that applying QoS techniques to VPNs was well-known in the art to support real-time applications like multimedia.
  • Motivation to Combine: A POSITA would combine Guillen's QoS teachings with Provino's VPN architecture to enhance its capabilities. Since Provino already used a dedicated internal nameserver (nameserver 32) for address resolution within the VPN, a POSITA would have found it obvious to modify this nameserver to also store and return QoS parameters, as taught by Guillen. This would allow Provino's system to support different service levels for various applications, a known benefit in the art.
  • Expectation of Success: A POSITA would have had a high expectation of success, as combining known QoS directory functions with a known VPN architecture was a predictable way to achieve a service-aware network. The integration involved applying a known data-provisioning technique (QoS parameters in DNS) to a known system element (a private nameserver).

4. Key Claim Construction Positions

• "secure domain name": Petitioner proposed this term be construed as "a non-standard domain name that corresponds to a secure computer network address and cannot be resolved by a conventional domain name service (DNS)." This construction was argued as crucial because it aligns with Provino’s disclosure of a "human-readable" address that fails at a conventional nameserver but resolves at a private, internal nameserver.
• "secure domain name service": Petitioner proposed this term means "a service that can resolve secure computer network addresses for a secure domain name for which a conventional domain name service cannot resolve addresses." This construction allows Provino’s internal nameserver (nameserver 32), which exclusively services the private VPN, to meet the claim limitation.
• "provisioning information": Petitioner argued for a broad construction of "information that enables communication in a virtual private network." This interpretation would encompass the QoS parameters taught by Guillen, which enable and control the quality of communications within the VPN.

5. Arguments Regarding Discretionary Denial

• Petitioner dedicated significant argument to preemptively address the one-year time bar under §315(b), as Petitioner had been a defendant in prior litigations involving the ’180 patent more than one year before this petition was filed.
• Dismissal "Without Prejudice": Petitioner argued that the prior litigations were terminated via a settlement that included a dismissal of Microsoft’s invalidity counterclaims "without prejudice." Petitioner contended that this type of dismissal nullifies the legal effect of the service of the complaint for §315(b) purposes, preserving its right to bring a future validity challenge, such as this IPR.
• Interpretation of "a complaint": As an alternative, Petitioner argued that the statutory language "served with a complaint" in §315(b) is ambiguous when multiple lawsuits are filed. Petitioner urged the Board to interpret it as referring to the most recent complaint, which would mean the one-year clock reset upon service of the complaint in the then-pending 2013 litigation, making the petition timely.

6. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1, 4, 6, 10, 12-15, 17, 20, 22, 26, 28-31, 33, 35, and 37 of the ’180 patent as unpatentable.