Hewlett Packard Enterprises Co v. Parity Networks LLC

1. Case Identification

• Case #: IPR2019-00373
• Patent #: 7,468,978
• Filed: November 30, 2018
• Petitioner(s): Hewlett Packard Enterprise Company
• Patent Owner(s): Parity Networks, LLC
• Challenged Claims: 1, 4, 12, 14, 15, and 16

2. Patent Overview

• Title: Method and Apparatus for Transferring Packets of Data on a Network
• Brief Description: The ’978 patent discloses methods and systems for transferring data packets from a source node in a private network (e.g., a VPN) through a public network (e.g., the Internet) and back to a destination node in the same private network. The core technique involves generating a value from a first header portion of a packet and including that value in a second header portion, which is then used to select one of multiple possible paths through the public network, enabling load balancing.

3. Grounds for Unpatentability

Ground 1: Obviousness over Jagannath and Callon - Claims 1, 4, 12, 14, 15, and 16 are obvious over Jagannath in view of Callon.

• Prior Art Relied Upon: Jagannath (Patent 7,095,740) and Callon (an Internet Engineering Task Force draft titled "A Framework for Multiprotocol Label Switching," Nov. 21, 1997).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Jagannath taught the foundational system for routing packets between nodes in a VPN across a public network using Multiprotocol Label Switching (MPLS). Jagannath disclosed using a VPN-ID in a label field to route packets but did not explicitly detail multipath routing or load balancing. Callon, which Jagannath expressly cited as defining the MPLS standard, filled this gap by teaching that MPLS standards must support multipath routing. Critically, Callon disclosed using a hash function on the source and destination IP addresses (from a packet's first header) to generate a value. This value could then be used to select a specific path for all packets in a given flow, thereby avoiding misordering while distributing traffic across multiple paths (i.e., load balancing). Petitioner contended that combining Callon’s hash-based multipath selection with Jagannath’s VPN-over-MPLS framework rendered the challenged claims obvious. The combination taught generating a value from a first header (per Callon), creating a second header containing this value, and using it to select a path on the second network (per Jagannath’s MPLS framework as enhanced by Callon).
  • Motivation to Combine: The primary motivation asserted was that Jagannath explicitly incorporated the MPLS standard defined by Callon. A person of ordinary skill in the art (POSITA) implementing Jagannath's system would have been directly motivated, if not required, to consult Callon to understand the MPLS standard's requirements. Upon doing so, the POSITA would learn from Callon that MPLS must support multipath routing and would find Callon’s specific teachings on using hash functions for path selection to be a natural and advantageous technique to implement within Jagannath's network, thereby making multipath routing more efficient.
  • Expectation of Success: Petitioner argued a POSITA would have had a high expectation of success. The proposed combination involved applying a known technique (Callon's hash-based load balancing) to a known type of system (Jagannath's MPLS-based VPN) to achieve a predictable result (efficient multipath routing and load balancing). Both references operated within the same field of IP networking and MPLS technology, making their teachings fully compatible.

4. Key Claim Construction Positions

• Petitioner argued for a specific construction of the path selection limitation in claims 1 and 12, such as "using the second header portion, selecting one of a plurality of possible paths..."
• Proposed Construction: "using the derived value in the second header portion, selecting one of a plurality of possible paths... such that different paths are selected for packets having different derived values."
• Rationale: Petitioner asserted this construction was required by the specification and the prosecution history of a parent patent. During prosecution, the patentee allegedly distinguished prior art by emphasizing that the "inventive nature" of the process was the ability to use a newly derived value to "load balance the packets on different paths." Petitioner argued this created a clear disavowal of scope, limiting the claims to systems where the derived value itself is the basis for selecting different paths, rather than merely being present in the header during path selection. This construction was central to mapping Callon's load-balancing teachings to the claims.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that the Board should not discretionarily deny the petition under 35 U.S.C. § 325(d).
• The core reason provided was that the primary prior art references, Jagannath and Callon, were not cited or considered by the examiner during the original prosecution of the ’978 patent. Therefore, the petition raised new questions of patentability that the Patent Office had not previously addressed.

6. Relief Requested

• Petitioner requests the institution of an inter partes review and cancellation of claims 1, 4, 12, 14, 15, and 16 of Patent 7,468,978 as unpatentable.