Cigna Corp v. Sound View Innovations LLC

1. Case Identification

• Case #: IPR2020-00924
• Patent #: 6,725,456
• Filed: May 15, 2020
• Petitioner(s): Cigna Corporation and Cigna Health and Life Insurance Company
• Patent Owner(s): Sound View Innovations, LLC
• Challenged Claims: 13 and 17

2. Patent Overview

• Title: Methods and Apparatus for Ensuring Quality of Service in an Operating System
• Brief Description: The ’456 patent discloses techniques for providing a desired quality of service (QoS) for applications in a computer system. The system uses a hierarchical scheduling model composed of nodes called "resource reservations" to guarantee minimum resource allocations and manage resource sharing.

3. Grounds for Unpatentability

Ground 1: Obviousness over Banga, Mercer, and Waldspurger - Claims 13 and 17 are obvious over Banga in view of Mercer and Waldspurger.

• Prior Art Relied Upon: Banga (a 1999 USENIX paper on "Resource Containers"), Mercer (a 1994 IEEE paper on "Processor Capacity Reserves"), and Waldspurger (a 1994 USENIX paper on "Lottery Scheduling").
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Banga disclosed the core framework of the claims through its "resource containers," which are hierarchical operating system entities that logically contain all resources used by an application to provide differentiated QoS. Petitioner contended that Mercer supplemented Banga by teaching the details of implementing "fixed-share scheduling" through "reserves," which guarantee a minimum amount of a resource (e.g., 30% of CPU time), thus satisfying the "minimum amount of resources" limitation. Waldspurger was argued to provide a known method for managing unreserved resources through "lottery scheduling," a proportional-share model where "lottery tickets" act as a "weight" that specifies how a child reservation shares its parent's unreserved resources with its siblings. For claim 17's limitation of a process being restricted to creating reservations descending from its own root, Petitioner asserted Banga suggested this by describing a web server creating a root container and child containers, and that adding standard access controls to enforce this hierarchy would have been an obvious, trivial modification to a POSITA.
  • Motivation to Combine: A POSITA would combine the references because Banga explicitly suggested using its resource containers with other management policies and cited both Mercer and Waldspurger as relevant, complementary technologies. Mercer provided the necessary implementation details for Banga's high-level disclosure of "guaranteed CPU shares." A POSITA would integrate Waldspurger's lottery scheduling, as suggested by both Banga and Mercer, to efficiently utilize unreserved system capacity, a known goal in operating system design.
  • Expectation of Success: A POSITA would have a reasonable expectation of success in combining these known OS scheduling techniques, as they were all designed to solve related problems in resource management and were described as being compatible.

Ground 2: Obviousness over McKusick and Goyal - Claim 13 is obvious over McKusick in view of Goyal.

• Prior Art Relied Upon: McKusick (a 1996 textbook, "The Design and Implementation of the 4.4BSD Operating System") and Goyal (a 1996 USENIX paper, "A Hierarchical CPU Scheduler for Multimedia Operating Systems").
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that McKusick described the 4.4BSD UNIX operating system, a well-known platform designed to be modular and easily modified, but which had a limited scheduler unsuitable for real-time applications. Goyal disclosed a hierarchical CPU scheduler that provides QoS guarantees by partitioning resources through a tree of nodes. Each node in Goyal's tree has a "weight" that performs two functions: (1) guaranteeing a "specified share" (a minimum amount) of its parent's bandwidth, and (2) ensuring any unused bandwidth is fairly allocated among active sibling nodes. Petitioner contended that Goyal's hierarchical nodes are the claimed "resource reservations," and its multi-faceted "weight" meets the limitations of both a minimum resource guarantee and a weight for sharing resources with siblings. The sum of the minimums guaranteed by child nodes in Goyal's examples equals the parent's total available resource, meeting the final limitation of claim 13.
  • Motivation to Combine: A POSITA would combine the references to solve a known problem: retrofitting the 4.4BSD operating system described in McKusick with a more sophisticated scheduler capable of supporting real-time applications. McKusick explicitly noted the need and attempts to improve BSD's scheduling for real-time performance. Goyal provided a well-documented, successful implementation of such a scheduler in a similar UNIX environment, making it an obvious candidate for substitution. The combination was presented as a simple replacement of one known element (a basic scheduler) with an improved one (Goyal's scheduler) to achieve a predictable result.
  • Expectation of Success: A POSITA would expect success because the modification involved swapping a modular component (the scheduler) in an OS expressly designed for such modification with a proven scheduler from a similar OS environment.

4. Arguments Regarding Discretionary Denial

• Petitioner argued extensively that discretionary denial would be improper under both 35 U.S.C. §325(d) and §314(a). The prior art combinations were asserted to be new and not cumulative of art considered during prosecution. Regarding the General Plastic factors, Petitioner argued it is unrelated to the petitioner in a co-pending IPR (IPR2020-00818) and asserted different grounds, meaning this is not an improper follow-on petition. Regarding the Fintiv factors, Petitioner argued that the parallel district court case was in its early stages, a stay was likely given the presiding judge’s history, the merits of the Petition were strong, and the challenge to claim 17 created no overlap with the co-pending litigation or IPR, all of which weigh in favor of institution.

5. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 13 and 17 of Patent 6,725,456 as unpatentable.