PTAB

IPR2025-01380

Red Hat Inc v. Competitive Access Systems Inc

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Multipath Communication Devices And Methods
  • Brief Description: The ’649 patent relates to methods and devices for establishing multipath network connections to aggregate bandwidth. The technology is described as a residential communications gateway (RCG) intended to enhance existing telephone lines to solve "last mile" bandwidth limitations.

3. Grounds for Unpatentability

Ground 1: Claims 1-23 are obvious over Kotzin, optionally in view of Peirce and Held.

  • Prior Art Relied Upon: Kotzin (Application # 2003/0026221), Peirce (Patent 5,878,040), and Held (a 2000 textbook titled Network Design Principles and Applications).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Kotzin, which was not considered during prosecution, discloses all limitations of the challenged claims. Kotzin teaches a bandwidth aggregation system where a primary wireless unit (a "data-requesting device") can share bandwidth with a plurality of other wireless units ("network-edge devices") to increase its effective bandwidth. Petitioner asserted that Kotzin’s system shows a data-source device (e.g., an internet server) receiving multipath information and sending different portions of a data stream to different network-edge devices, which then retransmit the data to the data-requesting device for reassembly. This, Petitioner contended, meets the core limitations of independent claims 1, 7, 13, 18, and 21, which variously recite methods and devices for establishing and sending data over such multipath connections. For limitations in dependent claims requiring a "connection ID" (e.g., claims 2 and 7), Petitioner argued this feature is inherent to Kotzin’s session-based system or would have been an obvious addition.
    • Motivation to Combine (for §103 grounds): Petitioner argued that although Kotzin alone renders the claims obvious, a person of ordinary skill in the art (POSITA) would have been motivated to combine Kotzin with Peirce and Held. Kotzin expressly teaches sharing bandwidth for a "particular communication or session" but does not detail the session identification mechanism. Peirce, which also relates to bandwidth sharing, explicitly discloses using a "session identifier" or "bundle ID" to coordinate data streams. A POSITA would combine Peirce’s session ID with Kotzin’s system to provide a known mechanism for distinguishing between communication sessions, thereby improving the reliability of Kotzin's system. Similarly, for claim 10’s requirement of notifying a device when all data has been sent, a POSITA would have looked to a general networking reference like Held, which teaches standard TCP handshake and notification protocols for ensuring complete and error-free data transmission.
    • Expectation of Success (for §103 grounds): A POSITA would have had a reasonable expectation of success in implementing Peirce’s session ID or Held’s notification protocols in Kotzin’s system, as these were well-known, standard techniques in packet-based communications used to solve predictable problems.

Ground 2: Claims 1-23 are obvious over Phatak, optionally in view of Held.

  • Prior Art Relied Upon: Phatak (a 2002 IEEE INFOCOM article titled "A Novel Mechanism for Data Streaming Across Multiple IP Links") and Held.
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Phatak, also not considered during prosecution, renders all challenged claims obvious. Phatak discloses a mechanism for streaming data across multiple IP links (e.g., cellular, WiFi, Ethernet) to aggregate bandwidth and improve reliability. The system involves a data source (Host A) splitting a data flow at the IP layer and distributing packets across multiple interfaces to a data-requesting device (Host B). Petitioner asserted this maps directly to the claimed methods. Phatak’s use of TCP/IP tuples and IP-in-IP tunneling to manage the multipath session was argued to teach the claimed "multipath information" and "connection ID." The hosts exchanging information about their available IP addresses constitutes receiving multipath information about network-edge devices capable of joining a connection.
    • Motivation to Combine (for §103 grounds): Petitioner contended that Phatak alone renders the claims obvious. However, to the extent Phatak does not explicitly teach notifying the data-requesting device upon completion of data transfer (claim 10), a POSITA would have been motivated to incorporate this functionality using standard protocols described in Held. Phatak’s system relies on TCP, and Held explains that standard TCP includes mechanisms like the FIN flag and three-way handshakes to manage and terminate connections, which inherently involves notifying endpoints about the status of data transmission. A POSITA would combine these known TCP features, as taught by Held, with Phatak’s system to ensure robust and complete data transfer, a predictable solution to a known problem.
    • Expectation of Success (for §103 grounds): Implementing standard TCP/IP notification features from Held into Phatak's TCP-based system would have been a routine task for a POSITA with a high expectation of success.

4. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial is not appropriate because the primary prior art references, Kotzin and Phatak, were not substantively considered during the original prosecution. Petitioner also noted that while a subset of claims were previously challenged in a separate inter partes review (IPR) by another party (IPR2023-00880), that proceeding was terminated prior to an institution decision, and Petitioner was not a party to that action.

5. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 1-23 of the ’649 patent as unpatentable under 35 U.S.C. §103.