Diorite Technology LLC v. Cisco Systems Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Diorite Technology, LLC (Texas)
  • Defendant: Cisco Systems, Inc. (Delaware)
  • Plaintiff’s Counsel: Russ August & Kabat
• Case Identification: 2:25-cv-00591, E.D. Tex., 09/04/2025
• Venue Allegations: Plaintiff alleges venue is proper in the Eastern District of Texas because Defendant Cisco has regular and established places of business within the district, specifically citing locations in Richardson, Texas.
• Core Dispute: Plaintiff alleges that Defendant’s enterprise communication products, including its VoIP, video conferencing, and collaboration platforms, infringe three patents related to intelligent call-back functionalities, graphical conference call interfaces, and networked mass audio notification systems.
• Technical Context: The technologies at issue aim to enhance the user experience and administrative control of modern enterprise communication systems, a market where usability and intelligent, context-aware features are significant competitive differentiators.
• Key Procedural History: The complaint does not mention any prior litigation, Inter Partes Review (IPR) proceedings, or licensing history related to the patents-in-suit.

Case Timeline

Date	Event
2007-06-21	U.S. Patent No. 8,189,759 Priority Date
2010-04-30	U.S. Patent No. 9,344,820 Priority Date
2011-06-21	U.S. Patent No. 9,007,421 Priority Date
2012-05-29	U.S. Patent No. 8,189,759 Issue Date
2015-04-14	U.S. Patent No. 9,007,421 Issue Date
2016-05-17	U.S. Patent No. 9,344,820 Issue Date
2025-09-04	Complaint Filing Date

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 8,189,759 - "System and Method for Automatic Call Back Using Availability Information," issued May 29, 2012 (’759 Patent)

The Invention Explained

• Problem Addressed: The patent’s background describes the traditional "Automatic Callback" (ACB) feature in phone systems as "very coarse" because it only considers whether a recipient's phone is on- or off-hook (Compl. Ex. 1, col. 1:29-31). This fails to account for situations where a user is physically present but unavailable (e.g., in a meeting), leading to inefficient or disruptive callbacks (Compl. Ex. 1, col. 1:31-34).
• The Patented Solution: The invention proposes an improved ACB system that integrates with modern presence and availability services, such as those used for instant messaging (Compl. Ex. 1, col. 2:54-59). The system's call controller "subscribes to the presence server" to receive more detailed status information (e.g., "Busy," "in a Meeting") and evaluates this richer data, along with call features like "Do Not Disturb," against a list of compatible states before initiating a callback (Compl. Ex. 1, col. 4:26-43, 57-61). This makes the callback more context-aware and increases the likelihood it will be answered appropriately.
• Technical Importance: The technology sought to bridge legacy telephony features with emerging, presence-aware unified communications platforms, making automated actions more intelligent and sensitive to a user's actual availability (Compl. Ex. 1, col. 2:54-59).

Key Claims at a Glance

• The complaint asserts independent Claim 1 (Compl. ¶10).
• Essential elements of Claim 1 include:
  • Initiating a call from a first device to a second device that fails.
  • Setting an automatic call back feature in a call controller.
  • Monitoring the called party's status at a "presence server" by receiving "status messages."
  • Evaluating the compatibility of the received status messages with a "list of compatible availability states."
  • Further evaluating the compatibility of a call feature selected by the called party (e.g., Do Not Disturb).
  • Initiating the callback only if the availability status is determined to be compatible.
• The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 9,007,421 - "Conference Call User Interface and Methods Thereof," issued April 14, 2015 (’421 Patent)

The Invention Explained

• Problem Addressed: The patent identifies that conventional conference phones often have a "very limited user interface" with a "button interface that is typically not intuitive" (Compl. Ex. 3, col. 1:23-28). This makes setting up and managing multi-party conference calls difficult, particularly for infrequent users (Compl. Ex. 3, col. 1:30-34).
• The Patented Solution: The invention describes a graphical user interface (GUI) on a touch-screen device that simplifies conference call management (Compl. Ex. 3, col. 2:35-43). The interface mimics a physical meeting room by displaying graphical "avatars" representing participants around a virtual conference table (Compl. Ex. 3, col. 4:36-40, 57-58). A user can add a participant by actuating a phone icon on an avatar, and can manage each connected party through a "participant panel" that provides call-handling options such as "Hold," "End Call," and "Escalate to Video" (Compl. Ex. 3, col. 6:55-68).
• Technical Importance: The invention aimed to make the complex task of managing a multi-party call more intuitive by replacing abstract button-based commands with a direct-manipulation, visual interface that provides a spatial metaphor for the conference (Compl. Ex. 3, col. 2:50-54).

Key Claims at a Glance

• The complaint asserts independent Claim 1 (Compl. ¶18).
• Essential elements of Claim 1 include:
  • An apparatus with a touch display, processor, and memory.
  • Displaying graphics representing a plurality of "characters" and the apparatus itself.
  • Displaying phone icons on the "characters" and the apparatus.
  • Connecting to a device when a phone icon is actuated.
  • Associating the connected device with one of the "characters."
  • Displaying the "character" with an identifier of the connected device.
  • Wherein connecting comprises displaying a "participant panel" associated with the character, the panel having "End Call," "Hold," "Escalate to Video," and "De-escalate from Video" options.
• The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 9,344,820 - "Method, Apparatus, and System for Mass Audio Notification Field," issued May 17, 2016 (’820 Patent)

Technology Synopsis

The ’820 Patent addresses the shortcomings of standalone, analogue mass notification systems, such as their lack of scalability and limited selective notification options (Compl. Ex. 5, col. 1:24-32). The patented solution is a system comprising a central server connected via an internet protocol network to a plurality of speakers, allowing the server to send audio data and control commands to specific speakers or groups of speakers and to receive status reports back from them (Compl. Ex. 5, col. 2:40-45).

Asserted Claims

The complaint asserts independent Claim 1 (Compl. ¶26).

Accused Features

The complaint accuses Cisco’s Webex and Webex Calling platforms, and Cisco products that support them (such as Cisco Desk devices and IP Phones), of infringement (Compl. ¶26).

III. The Accused Instrumentality

Product Identification

The complaint names several Cisco enterprise communication products and platforms as the "Accused Instrumentalities" (Compl. ¶¶10, 18, 26). These include:

• The Cisco Broadworks platform and VoIP hardware such as the Desk Phone 9800 Series (accused of infringing the ’759 Patent).
• Video conferencing devices including the Cisco Desk, Cisco Desk Mini, and Cisco Desk Pro (accused of infringing the ’421 Patent).
• Collaboration platforms Webex and Webex Calling, and supporting hardware such as the Cisco Desk devices and Cisco IP Phones (accused of infringing the ’820 Patent).

Functionality and Market Context

The complaint characterizes the accused products as integrated components of Cisco's unified communications offerings for businesses (Compl. ¶¶10, 18, 26). The allegations suggest these products provide advanced call management, video conferencing with graphical user interfaces, and the ability to manage communications across numerous networked endpoints. The complaint does not provide detailed technical descriptions of the accused products' operation, focusing instead on mapping their alleged high-level features to the patent claims. No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint states that claim charts are attached as exhibits but does not include them in the filing (Compl. ¶¶13, 21, 29). The analysis below is based on the narrative allegations.

’759 Patent Infringement Allegations

The complaint alleges that Cisco's VoIP products, powered by the Cisco Broadworks platform, infringe by implementing an intelligent automatic call-back feature (Compl. ¶10). The theory suggests that when a user places a call that fails, the Cisco system allows for a callback to be set. The system is then alleged to monitor the called party’s detailed availability status—beyond a simple on-hook/off-hook state—and to evaluate user-set call features (such as "Do Not Disturb") to determine the optimal time to initiate the return call, as required by Claim 1 (Compl. ¶13).

’421 Patent Infringement Allegations

The complaint alleges that Cisco's Desk series of video conferencing devices infringe by providing a graphical user interface for managing multi-party calls (Compl. ¶18). The infringement theory implies that the accused devices display graphical representations for conference participants (the claimed "characters"), allow a user to add new parties by interacting with these representations, associate a connected party with a specific graphical character on the screen, and provide a pop-up or panel with specific call-control functions for that participant, including options to hold the call, end the call, and manage the video feed (Compl. ¶21).

Identified Points of Contention

• Scope Questions (’759 Patent): A potential dispute may arise over whether the availability data used by the Cisco Broadworks platform constitutes "status messages" from a "presence server" as described in the patent, or if it relies on a different, integrated call-state management architecture that falls outside the claim scope.
• Technical Questions (’759 Patent): The complaint raises the question of what specific evidence will show that the accused system monitors discrete availability states (e.g., "in a meeting") and compares them against a "list of compatible availability states" to trigger a callback, as distinct from a more general availability check.
• Scope Questions (’421 Patent): A primary issue may be whether the term "characters," as used in Claim 1, can be construed to read on the specific graphical elements used in the Cisco Desk interface to represent conference participants.
• Technical Questions (’421 Patent): A key factual question will be whether the accused Cisco interface, when managing a participant, displays a single "participant panel" that contains the specific combination of four functions required by Claim 1: an "End Call" option, a "Hold" option, an "Escalate to Video" option, and a "De-escalate from Video" option.

V. Key Claim Terms for Construction

’759 Patent (Claim 1)

• The Term: "presence server"
• Context and Importance: The definition of this term is critical, as infringement hinges on whether the component within Cisco's architecture that supplies availability information is properly construed as a "presence server." Practitioners may focus on this term because the defense could argue that Cisco's system uses an integrated call controller rather than the distinct client-server model described in the patent's examples.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The specification describes presence services generally as "an emerging technology that provide information of user's availability and capabilities," which could support a construction not limited to a specific type of server (Compl. Ex. 1, col. 1:63-65).
  • Evidence for a Narrower Interpretation: The specification provides specific examples of presence servers tied to instant messaging platforms, such as "Microsoft® LCS, Lotus® SameTime," and protocols like "SIMPLE (SIP for Instant Messaging and Presence Leveraging Extensions)," which may support a narrower construction tied to that technological context (Compl. Ex. 1, col. 2:60-64; col. 3:50-51).

’421 Patent (Claim 1)

• The Term: "characters"
• Context and Importance: The infringement analysis for the ’421 patent will likely depend on the scope of this term and whether it covers the graphical representations of participants in the accused Cisco Desk interface.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The detailed description states that the "avatars 306 can be any character or object and is not limited to those shown," suggesting the term is not confined to human-like figures (Compl. Ex. 3, col. 4:65-67).
  • Evidence for a Narrower Interpretation: The specification consistently uses the term "avatars" when describing the "characters" and depicts them as stylized human figures in the drawings (e.g., Fig. 3), which could be cited to argue that the term "characters" implies some form of anthropomorphic representation (Compl. Ex. 3, col. 4:57).

VI. Other Allegations

Indirect Infringement

For all three patents, the complaint alleges induced infringement, asserting that Cisco's "user manuals and online instruction materials" instruct customers on how to use the accused products in an infringing manner (Compl. ¶¶11, 19, 27). The complaint also alleges contributory infringement, stating the products are "especially made or adapted to infringe" and are not staple articles of commerce suitable for non-infringing use (Compl. ¶¶12, 20, 28).

Willful Infringement

The complaint does not contain an explicit count for willful infringement. However, the inducement allegations assert that Cisco has had knowledge of the patents and their infringement "[t]hrough at least the filing and service of this Complaint," which could form the basis for alleging post-suit willful infringement if the accused conduct continues (Compl. ¶¶11, 19, 27).

VII. Analyst’s Conclusion: Key Questions for the Case

• A core issue will be one of architectural equivalence: does the availability-tracking functionality within Cisco’s allegedly monolithic Broadworks platform map onto the distinct "presence server" architecture described in the ’759 Patent, or does it represent a fundamentally different technology for managing call states?
• A key evidentiary question will be one of feature-for-feature mapping: does the user interface of the accused Cisco Desk products present the specific, four-element "participant panel" (with End, Hold, Escalate Video, and De-escalate Video options) required by Claim 1 of the ’421 Patent, or does its functionality differ in a way that avoids infringement?
• The dispute over the ’820 patent may center on a question of system definition: can the relationship between Cisco's Webex cloud services and its various hardware endpoints be characterized as the server-and-speaker system with distinct transport and signaling links as claimed in the patent, or is it a more integrated system outside the claim's scope?