VMware Inc v. Proven Networks LLC

1. Case Identification

• Case #: IPR2021-00196
• Patent #: 7,450,507
• Filed: November 16, 2020
• Petitioner(s): VMware, Inc. and Dell Technologies Inc.
• Patent Owner(s): Proven Networks, LLC
• Challenged Claims: 1-9 and 13-19

2. Patent Overview

• Title: Hierarchal Rate-Limiting at a Network Node That Utilizes an Infinity Rate-Limit Check
• Brief Description: The ’507 patent describes a method and system for managing data traffic in a communications network using hierarchical rate-limiting. The purported invention is the use of an "infinity rate-limit check" which allows a data packet that fails a rate-limit check at a lower (child) classification level to receive an "automatic pass," so its ultimate fate is decided by a rate-limit check at a higher (parent) classification level, thereby enabling bandwidth borrowing.

3. Grounds for Unpatentability

Ground I: Anticipation of Claims 1, 2, and 6-9 by Hussain

• Prior Art Relied Upon: Hussain (Patent 7,161,904).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Hussain teaches every limitation of the challenged method claims. Hussain discloses a hierarchical rate-limiting system where packets are subjected to checks at multiple levels. Critically, Hussain teaches a "no dropping" policy that can be applied to a packet that fails a rate-limit check at a child level. This policy, Petitioner asserted, is functionally identical to the ’507 patent’s "infinity rate-limit check," as it prevents the packet from being dropped and extends its life to be evaluated at a higher, parent level. This allows the packet to pass if the parent level has sufficient bandwidth, which is the same "bandwidth borrowing" concept described in the ’507 patent. Dependent claims related to overall pass/fail outcomes and parent-child relationships were also argued to be disclosed in Hussain's policy-based system.

Ground II: Obviousness of Claims 1-9 and 13-19 over Kiremidjian in view of Hussain

• Prior Art Relied Upon: Kiremidjian (Application # 2003/0081623) and Hussain (Patent 7,161,904).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner contended that Kiremidjian discloses a hardware-based, hierarchical rate-limiting system that performs checks for multiple classification levels in parallel. Kiremidjian’s system uses a credit-based system to control traffic flow and classifies packets based on various parameters. While Kiremidjian teaches the foundational hierarchical structure, it does not explicitly disclose a feature equivalent to the "infinity rate-limit check." Hussain, as argued in Ground I, supplies this missing element with its "no dropping" policy.
  • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Hussain’s "no dropping" policy with Kiremidjian’s system to implement the well-known technique of bandwidth borrowing. This would have been an attractive and obvious way to improve the configurability and efficiency of Kiremidjian's parallel, hardware-based system.
  • Expectation of Success: A POSITA would have had a reasonable expectation of success because Kiremidjian already described using configurable node-specific policy flags to control packet queueing. Implementing Hussain’s "no dropping" policy would simply involve defining a new "no queuing" flag to prevent a packet from being queued (or dropped) upon a rate-limit failure, which was a straightforward extension of Kiremidjian’s existing architecture.

Ground III: Obviousness of Claims 1-3, 6-9, 13-17, and 19 over Gingras

• Prior Art Relied Upon: Gingras (Patent 7,664,028).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Gingras discloses a two-level "hierarchical metering" system using primary (child-level) and secondary (parent-level) meters with token buckets. For each metering result (e.g., non-conformant), Gingras teaches that one of three actions can be specified: DISCARD, REMARK, or "NO ACTION." Petitioner asserted that selecting the "NO ACTION" option for a non-conforming packet at the primary meter is functionally identical to the ’507 patent’s "infinity rate-limit check." This action causes the system to ignore the primary meter's failure and pass the packet to the secondary (parent) meter for a final determination, thus enabling bandwidth borrowing.
  • Motivation to Combine: A POSITA would have been motivated to configure Gingras’s system to associate the "NO ACTION" option with a non-conforming outcome at the primary meter. This represented a simple and straightforward way to implement the well-known and desirable technique of bandwidth borrowing in a rate-limit hierarchy, a concept the ’507 patent itself acknowledged was part of the prior art.
  • Expectation of Success: A POSITA would have had a high expectation of success because Gingras explicitly taught that any of the three available actions could be associated with any of the metering outcomes, making the proposed configuration an inherent and intended option within the Gingras system.

4. Key Claim Construction Positions

• "Infinity rate-limit check": Petitioner argued this term was coined by the applicants of the ’507 patent and has no plain and ordinary meaning. Based on the patent’s specification, Petitioner proposed it should be construed as "a rule that grants an automatic pass to a packet at a child classification level regardless of the outcome of the rate-limit check at that child classification level." This construction is central to all grounds, as it allows Petitioner to equate this "coined term" with functionally identical, but differently named, concepts in the prior art, such as Hussain’s "no dropping" policy and Gingras’s "NO ACTION" rule.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under §314(a) and the Fintiv factors would be inappropriate. The core reasons provided were:
  • The petition was filed promptly and well within the one-year statutory bar.
  • The parallel district court litigation was in its very early stages, with fact discovery stayed and no significant investment of resources by the court or parties.
  • Petitioner VMware is not a party to the district court litigation and has interests beyond that case.
  • The petition raises different grounds and relies on different prior art than a co-pending IPR filed by another party (NetApp), mitigating concerns of duplicative efforts.

6. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 1-9 and 13-19 of the ’507 patent as unpatentable under 35 U.S.C. §102 and §103.