Silver Peak Systems Inc v. Riverbed Technology Inc

1. Case Identification

• Case #: IPR2014-00149
• Patent #: 8,321,580
• Filed: November 13, 2013
• Petitioner(s): Silver Peak Systems, Inc.
• Patent Owner(s): Riverbed Technology, Inc.
• Challenged Claims: 1-24

2. Patent Overview

• Title: Transaction Accelerator for Client-Server Communication Systems
• Brief Description: The ’580 patent describes methods and systems for accelerating data communication between clients and servers over a network. The core technique involves intercepting response data, determining if a portion of that data is already locally accessible to the recipient, and if so, replacing that portion with a smaller reference to instruct the recipient to retrieve the data from its local storage, thereby reducing data transmission over the network.

3. Grounds for Unpatentability

Ground 1: Claims 1-5, 7-12, 14-17, and 20-22 are obvious over Datta in view of APA.

• Prior Art Relied Upon: Datta (Application # 2003/0004998) and Admitted Prior Art (APA) from the ’580 patent specification.
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Datta, which was not before the Examiner, discloses the key inventive concept highlighted during prosecution: a system for caching web page fragments to improve delivery speeds. Datta teaches determining if content is locally accessible to a proxy cache and, if so, generating a template with a reference (a key) to that content instead of sending the full content. This modified response instructs the proxy cache to insert the locally stored fragment. Petitioner contended this directly maps to the ’580 patent's limitations of determining local accessibility, modifying response data by replacing a portion with a reference, and instructing the first apparatus to use the reference for retrieval. The APA was used to supply the general framework of client-server transactions being intercepted by proxies, as acknowledged in the ’580 patent’s background section.
  • Motivation to Combine: A Person of Ordinary Skill in the Art (POSA) would have been motivated to apply Datta's specific technique for efficient content delivery within the general proxy architecture described by APA. This combination represented a simple substitution of a known technique (Datta's fragment caching) into a known system (APA's proxy servers) to achieve the predictable result of improved network performance.
  • Expectation of Success: A POSA would have had a high expectation of success, as combining a known caching method with a standard proxy architecture was a common approach to enhancing performance.

Ground 2: Claims 6, 13, 18-19, and 23-24 are obvious over Datta and APA, in further view of Singh and Tolly.

• Prior Art Relied Upon: Datta (Application # 2003/0004998), APA, Singh (Patent 6,856,651), and Tolly (a 2001 performance evaluation).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground built upon Ground 1 to address the dependent claims reciting a specific network topology: a first apparatus (proxy) communicating with a first computer over a local area network (LAN), a second apparatus communicating with a second computer over a second LAN, and the two apparatuses communicating with each other over a wide area network (WAN). Petitioner asserted that Singh and Tolly explicitly teach this exact architecture. Tolly describes and illustrates a test bed for a Peribit networking product (based on Singh's technology) that shows two LANs (a branch office and a corporate office) connected via a WAN, with network appliances placed at the edge of each LAN to optimize traffic over the WAN link.
  • Motivation to Combine: The motivation was to implement the performance-enhancing system of Datta and APA in the well-known LAN-WAN-LAN enterprise network environment described by Singh and Tolly. A POSA seeking to improve bandwidth utilization across a WAN—a primary goal of the ’580 patent—would naturally look to apply caching and data reduction techniques at the gateways between the LANs and the WAN, as shown by Tolly.
  • Expectation of Success: Implementing a known optimization technique within a standard network configuration was a predictable and routine design choice, ensuring a high expectation of success.

Ground 3: Claims 1-5, 7, and 15-17 are obvious over Singh in view of APA.

• Prior Art Relied Upon: Singh (Patent 6,856,651) and APA.
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner presented this as an alternative ground where Singh, rather than Datta, provides the core data reduction technique. Singh teaches a system for improving bandwidth utilization by detecting repeated phrases in a data stream and replacing subsequent instances with a reference to an entry in a dictionary. Petitioner argued this is analogous to the ’580 patent’s claims. Singh discloses determining if a data phrase has been seen before (i.e., is locally accessible in the dictionary) and, if so, replacing it with a reference number. The receiving system then uses this reference to reconstruct the original data from its synchronized dictionary. As in Ground 1, APA supplied the context of using this technique within a client-server proxy architecture.
  • Motivation to Combine: A POSA would have been motivated to combine Singh's powerful data compression method with the standard proxy framework of APA to reduce bandwidth consumption for client-server traffic. The Examiner in related reexaminations had previously found this combination to be obvious for providing the known advantage of applying data compression to client-server transactions.
  • Expectation of Success: Applying a known compression algorithm like Singh's to a standard network proxy was a well-understood method for improving network efficiency, leading to a clear expectation of success.
• Additional Grounds: Petitioner asserted an additional obviousness challenge (Ground 4) against claims 6, 18, and 19 based on the combination of Singh, APA, and Tolly, which parallels the logic of Ground 2 by applying the Singh/APA system to the specific LAN-WAN-LAN network topology disclosed by Tolly.

4. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1-24 of Patent 8,321,580 as unpatentable.