PTAB

IPR2025-00840

Docker Inc v. Intellectual Ventures II LLC

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Root Image Caching and Indexing for Block-Level Distributed Application Management
  • Brief Description: The ’844 patent describes a block-level “branching store file system” for managing different versions of a file system for multiple compute nodes. The system uses a shared, read-only base image (“root image”) and unique, node-specific images (“leaf images”) that store only the changes made by each node to the root image.

3. Grounds for Unpatentability

Ground 1: Caching Claims Obviousness over Menage - Claims 1-13 are obvious over Menage

  • Prior Art Relied Upon: Menage (Patent 6,618,736)
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Menage discloses all limitations of the “caching” claims (1-13). Menage describes a system for creating file systems for multiple virtual private servers (analogous to compute nodes) using a set of shared storage units for common data (the claimed “root image”) and a set of private storage units for changes made by each virtual server (the claimed “leaf images”). Critically, Petitioner asserted that Menage’s leaf images inherently store only changes to the initial file system and new data, not unchanged blocks from the root, thus teaching the key limitation added during prosecution of the ’844 patent. Menage further explicitly taught that its shared storage units could be easily cached for high-speed access, meeting the caching limitation of claim 1.
    • Key Aspects: Petitioner contended that Menage, which was not considered during prosecution, teaches the core inventive concept of the ’844 patent, including the specific copy-on-write mechanism that led to the claims' allowance.

Ground 2: Indexing Claims Obviousness over Menage and Murphy - Claims 14-27 are obvious over Menage in view of Murphy

  • Prior Art Relied Upon: Menage (Patent 6,618,736) and Murphy (Patent 7,395,324)
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Menage provides the foundational root/leaf file system architecture as described in Ground 1. Murphy, which also was not considered during prosecution, addresses the "indexing" limitations of claims 14-27 by teaching a system for remotely managing computers. Murphy’s system uses a “file administration program” to create an index of files contained within a boot “image file” (analogous to Menage’s root image). Murphy further disclosed that this index file can be stored on a shared server, making it accessible to other client computers. This combination, Petitioner asserted, renders the indexing and sharing of indexing results limitations obvious.
    • Motivation to Combine: A POSITA would combine Murphy’s well-known indexing technique with Menage’s file system to achieve the known and predictable benefit of more efficient file search and location. Applying a known technique (indexing) to improve a similar system (Menage's shared file system) would have been a simple and logical design choice.
    • Expectation of Success: A POSITA would have had a high expectation of success because both Menage and Murphy describe systems where multiple clients share a base file system, and file system indexing was a well-understood computing technique used to improve performance in such environments.

Ground 3: Caching Claims Obviousness over Birse and Rothman - Claims 1-13 are obvious over Birse in view of Rothman

  • Prior Art Relied Upon: Birse (Patent 7,089,300) and Rothman (Patent 7,398,382)

  • Core Argument for this Ground:

    • Prior Art Mapping: As an alternative to Menage, Petitioner argued Birse provides a base system for the caching claims. Birse described a net-booted computer system where multiple clients (“compute nodes”) access a protected, read-only master copy of an operating system from a server's “system volumes” (the “root image”). Birse’s system also used client-specific “shadow volumes” that store only user-initiated changes to the operating system, which Petitioner equated to the claimed “leaf images.” Rothman was cited for its teaching of caching techniques for network booting, where a boot image is cached at a network device proximate to the client to reduce network traffic and improve boot speed on subsequent requests.
    • Motivation to Combine: A POSITA would have been motivated to incorporate Rothman's caching techniques into the Birse system for the clear benefit of faster access to frequently requested data. This would improve the performance of Birse's net-booted environment, a common goal in system design.
    • Expectation of Success: The expectation of success would have been high, as caching was a ubiquitous technique for improving performance in computer storage and network systems. Both references operate in the same field of network-booted clients accessing a base image, making the combination straightforward.

  • Additional Grounds: Petitioner asserted that claims 14-27 are obvious over Birse in view of Murphy, applying the same indexing logic from Ground 2 to the alternative base file system taught by Birse.

4. Relief Requested

  • Petitioner requests institution of an inter partes review (IPR) for claims 1-27 of the ’844 patent and cancellation of those claims as unpatentable under 35 U.S.C. §103.