Workspot Inc v. Citrix Systems Inc

1. Case Identification

• Case #: IPR2019-01002
• Patent #: 8,135,843
• Filed: April 19, 2019
• Petitioner(s): Workspot, Inc.
• Patent Owner(s): Citrix Systems, Inc.
• Challenged Claims: 1, 5, 7-9, 12, 16, 18-19, 23-24, 29-30

2. Patent Overview

• Title: Methods and Systems for Providing Access to an Application
• Brief Description: The ’843 patent describes methods for publishing graphical user interface applications on the web. The disclosed system architecture enables a client device to receive access information for a remote application from a web service directory, use that information to get address details from a web server, and then connect to the application on an application server.

3. Grounds for Unpatentability

Ground 1: Claims 1, 5, 7-9, 12, 16, 18-19, 23-24, 29-30 are obvious over Craft in view of Duursma.

• Prior Art Relied Upon: Craft (a 2000 publication titled "Configuring Citrix MetaFrame for Windows 2000 Terminal Services") and Duursma (WO 00/39678).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Craft taught all elements of the challenged claims. Craft described the Citrix NFuse system, where a client's web browser connects to a web server and receives a list of published applications as icons. Petitioner asserted these icons are "service access points." When a user clicks an icon (a hyperlink), the client downloads a configuration file (.ICA file) from the web server. This file contained the "address information" (e.g., the IP address) of the least busy application server. The client then launched a local ICA Client (the "second application") which used this address information to connect to the remote application server via a presentation layer protocol (the ICA protocol).
  • Motivation to Combine: Petitioner asserted an express motivation to combine because Craft explicitly referenced Citrix's "Program Neighborhood," and Duursma provided further technical details on that exact system. Duursma confirmed that Program Neighborhood functions as a web service directory, can be implemented using directory services like X.500, and that its application icons are encoded URLs (i.e., hyperlinks). A POSITA would have consulted Duursma to better understand the system described in Craft.
  • Expectation of Success: Petitioner contended that combining Craft and Duursma would yield predictable results, as Duursma merely elaborated on a known technology already mentioned by Craft.

Ground 2: Claims 1, 5, 7-9, 12, 16, 18-19, 23-24, 29-30 are obvious over Zoller in view of Craft and Duursma.

• Prior Art Relied Upon: Zoller (Patent 6,836,786), Craft, and Duursma.
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued Zoller taught a system for remote terminal server access using standard web protocols. In Zoller, a client browser receives an "Application Launching" web page from a content/web server. This page contained icons for applications like Microsoft Word. Petitioner asserted these icons, which were hyperlinks pointing to the web server, constituted "service access points" from a "web service directory." When a user selected an icon, the web server generated and returned a new web page containing the application's directory location on a terminal server ("address information") and embedded ActiveX controls. The browser then launched the ActiveX control (the "second application"), which used the address information to connect to the terminal server via a presentation layer protocol.
  • Motivation to Combine: A POSITA would combine Zoller with Craft because Zoller described using Microsoft Terminal Services with "proprietary protocols," and Craft disclosed that the well-known presentation protocol for Terminal Services is Remote Desktop Protocol (RDP). A POSITA would have used the known RDP protocol to implement Zoller’s system. Furthermore, a POSITA would have been motivated to combine Zoller with Duursma to improve Zoller's static application launching page. Duursma taught using a dynamic directory service to programmatically generate application lists based on user authorization, a known technique that would improve Zoller's usability for administrators.
  • Expectation of Success: Petitioner argued the combination would be a predictable application of known technologies to improve an existing system.

4. Key Claim Construction Positions

• "Service Access Point": Petitioner proposed the construction "a hyperlink, URL, or other unique address." This construction was central to mapping the prior art, as it allowed application icons displayed in a web browser (as in Craft and Zoller) to be considered "service access points."
• "Web Service Directory": Petitioner proposed "a directory providing a service access point." This broad construction supported the argument that the web pages in Craft and Zoller that listed available applications qualified as the claimed directory.
• "Content Server" and "Web Server": Petitioner argued that, based on the patent's specification, the claimed "content server" and "web server" are not required to be separate physical machines and can be implemented on a single server. This interpretation was important for applying Zoller, which disclosed a single "content/web server."

5. Key Technical Contentions (Beyond Claim Construction)

• Petitioner contended that the claims do not require direct communication between the client and the web service directory. It argued a POSITA would understand that intermediary servers are common in internet communications and that the claims should not be narrowly read to exclude them. This was critical to arguing that Craft's architecture, where a client communicates with a web server that in turn communicates with a content server, met the claim limitations.

6. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under §325(d) would be inappropriate because the primary prior art references relied upon (Craft, Duursma, and Zoller) were not cited or considered during the original prosecution of the ’843 patent.

7. Relief Requested

• Petitioner requested institution of an IPR and cancellation of claims 1, 5, 7-9, 12, 16, 18-19, 23-24, and 29-30 of the ’843 patent as unpatentable.