PTAB

IPR2016-00747

Activision Blizzard Inc v. Acceleration Bay LLC

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Petition
petition Intelligence

1. Case Identification

2. Patent Overview

  • Title: Method For Leaving a Multicast Computer Network
  • Brief Description: The ’147 patent discloses a method for a computer to disconnect from a multicast computer network that is structured as a "non-complete, m-regular graph." The method aims to "heal" the network by forming new connections between the neighbors of the departing computer, thereby maintaining the m-regular characteristic of the network topology.

3. Grounds for Unpatentability

Ground 1: Obviousness over Shoubridge, Denes, and Rufino - Claims 1-16 are obvious over Shoubridge in view of Denes and Rufino.

  • Prior Art Relied Upon: Shoubridge (a 1997 IEEE conference paper), Denes (a 1979 mathematics journal article), and Rufino (a 1992 IEEE conference paper).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the primary references collectively disclose all limitations of the challenged claims. Shoubridge taught a dynamic, 4-regular, non-complete computer network with a "torus" topology where nodes could fail or be mobile. This established the claimed network environment. Denes, a foundational work in graph theory, taught the precise mathematical algorithm for removing a node from an m-regular graph while preserving its regularity. This is achieved by disconnecting the departing node and connecting its former neighbors to one another in pairs. Rufino taught the practical messaging protocols for managing node departure in a token-ring network (a 2-regular graph). This included a departing node sending a set_successor disconnect message containing neighbor address information to its predecessor, and a node broadcasting a who_follows search message to find a new connection after a neighbor fails.
    • Motivation to Combine: A POSITA would combine these references to enhance the reliability of the dynamic network described in Shoubridge. When a node leaves such a network, it is desirable to maintain the m-regular topology to prevent bottlenecks. A POSITA would look to well-known graph theory principles and find Denes's explicit algorithm for this exact problem. To implement Denes’s abstract mathematical steps, a POSITA would naturally turn to a known messaging protocol like Rufino's to coordinate the disconnection and reconnection between nodes. Petitioner asserted it was well known to expand Rufino's 2-regular ring concepts to m-regular grid topologies.
    • Expectation of Success: A POSITA would have a reasonable expectation of success because combining the references involved applying a known mathematical solution (Denes) to a known problem (maintaining topology in Shoubridge's dynamic network) using a standard messaging implementation (Rufino).

Ground 2: Obviousness over Shoubridge, Denes, Rufino, and Hirviniemi - Claims 4-5, 14, and 16 are obvious over the combination of Ground 1 in further view of Hirviniemi.

  • Prior Art Relied Upon: The combination from Ground 1, and Hirviniemi (Patent 5,802,285).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground specifically addressed dependent claims requiring the network to be implemented using the "Internet" and "TCP/IP" connections. Petitioner argued that to the extent the primary combination did not explicitly teach these limitations, Hirviniemi supplied the missing element. Hirviniemi taught a method for interfacing network software, such as that used in a local area network, to a wide area network like the Internet using the TCP/IP protocol.
    • Motivation to Combine: A POSITA seeking to implement the network from the primary combination would be motivated to use the Internet and TCP/IP. These were ubiquitous, standard technologies for ensuring network compatibility, usefulness, and mass reach. Hirviniemi demonstrated that applying TCP/IP to connect different network types was routine and advantageous.

Ground 3: Obviousness over Shoubridge, Denes, Rufino, and Balph - Claims 8 and 13 are obvious over the combination of Ground 1 in further view of Balph.

  • Prior Art Relied Upon: The combination from Ground 1, and Balph (Patent 4,700,185).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground addressed dependent claims requiring a node to send a message accepting a proposal to connect. Petitioner contended that if Rufino did not sufficiently disclose this feature, Balph did. Balph taught a "request with response" mechanism for a token bus network where a receiving station responds to a request frame, thereby confirming and accepting a proposed connection.
    • Motivation to Combine: A POSITA implementing the connection protocol of Rufino would be motivated to incorporate the explicit request-and-response handshake taught by Balph. This was a well-known method for maximizing reliability, avoiding network confusion, and confirming that a connection was successfully established before proceeding, representing a standard and predictable design choice.

  • Additional Grounds: Petitioner asserted an alternative ground (Ground 4) challenging claims 1-16 as obvious over Shoubridge, Denes, Rufino, and Todd. This ground proposed Todd (a 1994 IEEE journal article) as an alternative to Rufino, arguing Todd explicitly teaches expanding 2-regular token ring messaging to a 4-regular token grid network, reinforcing the motivation to apply such messaging to Shoubridge's 4-regular topology.

4. Key Claim Construction Positions

  • “m-regular”: Petitioner proposed that this term, central to the patent, means "each node is connected to exactly m other nodes." This construction defines the fundamental topological constraint that the patent's method purports to maintain during node departure.

5. Relief Requested

  • Petitioner requested the institution of an inter partes review and the cancellation of claims 1-16 of the ’147 patent as unpatentable under 35 U.S.C. §103.