Unified Patents LLC v. American Patents LLC

1. Case Identification

• Case #: IPR2019-00482
• Patent #: 7,373,655
• Filed: December 27, 2018
• Petitioner(s): Unified Patents Inc.
• Patent Owner(s): American Patents LLC
• Challenged Claims: 5-7

2. Patent Overview

• Title: Control of access to network resources
• Brief Description: The ’655 patent discloses a method for controlling access to network resources. The method involves a user connecting to a pre-authorized network element; if the user is authorized, the user is allowed to "assume the identity" of the network element to access resources that the element is permitted to access.

3. Grounds for Unpatentability

Ground 1: Claims 5 & 6 are obvious over Coile in view of Templin

• Prior Art Relied Upon: Coile (Patent 6,473,406) and Templin (Patent 5,781,550).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Coile, which was not considered during prosecution, teaches the core limitations of independent claim 5. Coile describes a proxy server system where a client (user), who is not authorized to connect to a protected server, connects instead to a proxy server that is pre-authorized to access that server's resources. The proxy receives the user's request and authenticates the user before relaying communications. Petitioner contended that this maps to the claim limitations of arranging a pre-authorized network element, receiving a user request, and determining user authorization. For the limitation of "allowing the user to assume the identity of the network element," Petitioner argued that while Coile's proxy "stands in for" the protected machine, Templin is needed to explicitly teach this concept. Templin discloses a secure gateway that intercepts a packet from a trusted host, consumes it, and generates a new packet with the gateway's source address. This makes the trusted host appear to the destination as if it were the gateway, thereby assuming its identity. Dependent claim 6, which requires the network element be coupled to one or more network servers, was allegedly met by Coile's disclosure of a proxy connected to a server providing network services.
  • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Coile and Templin to gain the security benefits disclosed in Templin. Templin's method of address replacement acts as an "invisible middleman" that prevents the destination server from learning the originating client's identity. A POSITA would have been motivated to incorporate this security feature into Coile's known proxy architecture to create a more secure and transparent connection, a stated goal of Coile.
  • Expectation of Success: A POSITA would have had a reasonable expectation of success because Templin explicitly teaches how to implement the secure gateway by configuring a proxy to consume a packet and generate a new one with a different source address. This was a predictable implementation of known networking principles.

Ground 2: Claim 7 is obvious over Coile in view of Templin further in view of Hu

• Prior Art Relied Upon: Coile (Patent 6,473,406), Templin (Patent 5,781,550), and Hu (Patent 5,586,260).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground addresses dependent claim 7, which adds the limitation of "checking an identity characteristic of the user to determine whether the user is authorized." Petitioner argued that Coile's teaching of an "authentication or password procedure" inherently discloses checking an identity characteristic like a username. To bolster this position, Petitioner introduced Hu. Hu explicitly discloses an "authentication gateway" where a client provides a "user name and password" to verify "the identity of the client." Petitioner asserted that Hu's explicit disclosure of checking a username as an identity characteristic renders the limitation obvious.
  • Motivation to Combine: A POSITA would combine Hu's teachings with the Coile/Templin framework to improve the user authentication process. Petitioner argued that Coile's system could be interpreted as requiring two separate, undesirable authentication steps (once with the proxy, again with the server). Hu teaches a more efficient authentication gateway that provides client access to server systems without embedding passwords or requiring repeated authentications. This benefit would have motivated a POSITA to integrate Hu’s streamlined authentication method into the base proxy system.
  • Expectation of Success: Success would be expected because Hu provides detailed flow diagrams and descriptions for implementing its authentication gateway system, making its integration with a proxy server a predictable design choice.

• Additional Grounds: Petitioner asserted an additional obviousness challenge (Ground 3) against claims 5-7 based on Shapiro (Patent 5,991,810) in view of Coile and Templin. This ground relied on a similar combination theory, with Shapiro providing the base proxy system and Coile and Templin adding teachings of pre-authorization and assuming a network identity, respectively.

4. Key Claim Construction Positions

• "assume the identity" / "assuming the identity": Petitioner argued that these terms, recited in claim 5, are not explicitly defined in the ’655 patent. Based on the patent’s summary of the invention, which states that upon authorization, "the authorized user assumes the identity of the machine and appears to the network as if it were that machine," Petitioner contended that a POSITA would understand these phrases to mean, at a minimum, "appearing to the network as if it were" the network element. This construction was central to Petitioner's argument that Templin's address-swapping gateway met the claim limitation.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that the Board should not exercise its discretion to deny institution under 35 U.S.C. §314(a) or §325(d). The primary reasons asserted were that none of the prior art references relied upon in the petition were cited or served as the basis for rejection during the original prosecution of the ’655 patent. Furthermore, Petitioner noted that the ’655 patent had not been challenged in any previous IPR petition, making many discretionary denial factors inapplicable.

6. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 5-7 of the ’655 patent as unpatentable.