NetApp Inc v. Crossroads Systems Inc

1. Case Identification

• Case #: IPR2015-00773
• Patent #: 7,051,147
• Filed: February 19, 2015
• Petitioner(s): NetApp Inc.
• Patent Owner(s): Crossroads Systems, Inc.
• Challenged Claims: 1-13

2. Patent Overview

• Title: Storage Router for Providing Virtual Local Storage
• Brief Description: The ’147 patent discloses a storage router system that provides host devices with virtual local storage on remote storage devices. The system uses technologies like Fibre Channel (FC) transport mediums and a supervisor unit to manage a configuration that maps hosts to specific storage regions and implements access controls.

3. Grounds for Unpatentability

Ground 1: Obviousness over CRD-5500 and Smith - Claims 1-13 are obvious over the CRD-5500 User Manual and Data Sheet in view of Smith.

• Prior Art Relied Upon: CRD-5500 User Manual (a 1996 RAID controller manual), CRD-5500 Data Sheet (a 1996 data sheet), and Smith (a 1996 journal article on the Tachyon chip).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that the CRD-5500 references taught a RAID controller that functions as the claimed "storage router." This controller provided virtual local storage by mapping "redundancy groups" on physical disks to host-specific Logical Unit Numbers (LUNs) via a "Host LUN Mapping" feature, which met the limitations for mapping storage and controlling access. Smith disclosed the "Tachyon" chip, a well-known, off-the-shelf component for bridging between Fibre Channel (FC) and SCSI protocols. Petitioner contended that integrating Smith's Tachyon chip into the I/O modules of the CRD-5500 controller would create the claimed first and second FC controllers. The CRD-5500's main processor was alleged to function as the claimed "supervisor unit."
  • Motivation to Combine: A person of ordinary skill in the art (POSITA) would combine these references because the CRD-5500 Data Sheet explicitly stated that its architecture was designed to support high-speed serial interfaces like Fibre Channel. Smith's Tachyon chip was a readily available and logical solution to implement this suggested FC capability. The motivation was to leverage the known benefits of FC, such as higher bandwidth and longer connection distances, for the CRD-5500 storage system.
  • Expectation of Success: The combination was predictable, involving the integration of a standard protocol-bridging chip into a modular controller designed for such upgrades.

Ground 2: Obviousness over Kikuchi and Bergsten - Claims 3, 6-9, and 12 are obvious over Kikuchi in view of Bergsten.

• Prior Art Relied Upon: Kikuchi (Patent 6,219,771) and Bergsten (Patent 6,073,209).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Kikuchi disclosed a control device connecting FC hosts to SCSI storage, which performed host-level access control by referencing an address registration unit. Bergsten taught a more detailed FC-to-SCSI bridging architecture using emulation and physical drivers, along with advanced virtual mapping of logical to physical addresses. The proposed combination would use Kikuchi's fundamental access control framework but enhance its bridging and virtualization capabilities with the more sophisticated driver-based system from Bergsten.
  • Motivation to Combine: A POSITA would combine the references to improve the Kikuchi system with the superior virtualized, networked storage functionality taught by Bergsten. Bergsten noted the desirability of a storage controller that was independent of specific host or storage hardware, a key advantage of its virtualization scheme. Incorporating this into Kikuchi would increase the number of accessible storage devices and enhance system flexibility and scalability.
  • Expectation of Success: Petitioner argued the architectures were compatible, making the integration of Bergsten's driver-based virtualization into Kikuchi's controller a routine and predictable modification for a skilled engineer.

Ground 3: Obviousness over Bergsten and Hirai - Claims 3, 6-9, and 12 are obvious over Bergsten in view of Hirai.

• Prior Art Relied Upon: Bergsten (Patent 6,073,209) and Hirai (JP Application # Hei 5[1993]-181609).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground began with Bergsten's storage controller, which provided FC-to-SCSI bridging and two-stage virtual mapping. Petitioner argued that Hirai supplemented Bergsten by teaching a highly granular, partition-level access control system. Hirai described using a partition control table to assign specific access rights (e.g., read, write, create, delete) to different hosts for distinct storage partitions. This detailed access control map from Hirai would be implemented within Bergsten's supervisor unit to manage storage access.
  • Motivation to Combine: While Bergsten mentioned basic write-protection, a POSITA would have been motivated to incorporate Hirai's more comprehensive and nuanced access control system to provide additional layers of security. This would allow an administrator to set varying levels of access (e.g., read-only for some users, full access for others) for specific blocks of data, enhancing the security and utility of Bergsten's networked storage system.
  • Expectation of Success: Petitioner contended that applying Hirai's logical access control framework onto Bergsten's logical addressing scheme was a predictable design choice with a high expectation of success for a POSITA in the field of network storage design.

4. Key Claim Construction Positions

• Petitioner argued for a construction of "native low-level block protocol" (NLLBP) that includes protocols like SCSI and Fibre Channel Protocol (FCP). This construction distinguishes NLLBPs from higher-level network protocols (like TCP/IP) that require translation and add overhead. This interpretation was critical for Petitioner's arguments because the prior art systems operated using SCSI and FCP, and establishing them as NLLBPs was necessary to meet the claim limitations.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under 35 U.S.C. §325(d) would be inappropriate despite a previous, related IPR petition (IPR2014-01209) being denied institution. Petitioner asserted the prior denial was based solely on a procedural error—improperly incorporating arguments by reference from an expert declaration—rather than a substantive review of the merits. It was argued that the present petition corrected this defect by presenting all evidence and arguments within the four corners of the document, similar to another related and successfully instituted IPR (IPR2014-01207), and therefore warranted full consideration.

6. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 1-13 of Patent 7,051,147 as unpatentable.