Communication Interface Tech LLC v. Keller Williams Realty Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Communication Interface Technologies, LLC (Delaware)
  • Defendant: Keller Williams Realty Inc. (Texas)
  • Plaintiff’s Counsel: Beaty Legal PLLC
• Case Identification: 4:23-cv-00498, E.D. Tex., 05/30/2023
• Venue Allegations: Plaintiff alleges venue is proper because Defendant maintains multiple established places of business within the Eastern District of Texas.
• Core Dispute: Plaintiff alleges that Defendant’s mobile real estate application infringes three expired patents related to establishing and efficiently resuming client-server communication sessions, a technology described as "virtual sessions."
• Technical Context: The patents address methods for maintaining a persistent software session between a client and server even when the underlying physical network connection is intermittent, a foundational concept for modern mobile applications.
• Key Procedural History: The complaint notes that the patents-in-suit have been subject to extensive prior litigation against numerous defendants, with most prior cases having been dismissed or settled before claim construction. The complaint also states that there are more than 180 licensees to the patents and identifies two other pending lawsuits asserting the same patents. All three asserted patents have expired, limiting Plaintiff's potential remedies to past damages.

Case Timeline

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

U.S. Patent No. 6,574,239 - "VIRTUAL CONNECTION OF A REMOTE UNIT TO A SERVER" (issued June 3, 2003)

The Invention Explained

• Problem Addressed: The patent’s background section describes the inefficiency and high cost associated with mobile workers needing to maintain continuous connections to a central server, particularly over cellular or long-distance dial-up links where airtime is expensive (Compl. ¶¶11-12; ’239 Patent, col. 2:15-24). Manually re-establishing connections was described as tedious and disruptive to workflow (Compl. ¶12; ’239 Patent, col. 2:41-44).
• The Patented Solution: The invention proposes a "virtual session" layer that maintains the parameters of a communication session (e.g., authentication, encryption keys) in memory on both the client and server even after the physical connection is terminated (’239 Patent, col. 3:44-51). When communication is needed again, the session can be quickly reactivated using these stored parameters, avoiding the time-consuming process of a full, from-scratch negotiation (’239 Patent, col. 4:56-67, FIG. 5). The server can also initiate a reactivation by "dialing-out" to the remote unit to deliver new data (’239 Patent, FIG. 7).
• Technical Importance: This "fast reconnect" method was aimed at making intermittently connected applications feel seamless to the user, a key challenge in the early days of mobile and wireless computing (Compl. ¶16).

Key Claims at a Glance

• The complaint explicitly asserts dependent claim 7, which relies on independent claim 1 (Compl. ¶39).
• Essential elements of independent claim 1 (a method for use on a server) include:
  • establishing a virtual session with a remote unit, instantiated to support an application layer program
  • placing the virtual session in an inactive state
  • dialing a telephone number corresponding to the remote unit to cause a ring signal followed by caller identification data to be delivered
  • placing the virtual session back into the active state and transferring data
• The complaint reserves the right to assert other claims (Compl. ¶41).

U.S. Patent No. 8,266,296 - "APPLICATION-LAYER EVALUATION OF COMMUNICATIONS RECEIVED BY A MOBILE DEVICE" (issued September 11, 2012)

The Invention Explained

• Problem Addressed: As part of the same patent family, the ’296 Patent addresses the same general problem of efficiently managing communications for mobile devices over intermittent connections (Compl. ¶¶11-12; ’296 Patent, col. 2:44-52).
• The Patented Solution: The invention focuses on the client-side (mobile device) process. It describes a method where a "control program" on the device receives an unsolicited communication from a remote server (’296 Patent, Abstract). This communication contains information that identifies a specific application program on the device. The control program evaluates this information, launches the corresponding application, and reactivates a communication session with the server, enabling the application to process the new data (’296 Patent, claim 1). This process is analogous to how modern push notifications are handled by a mobile operating system (Compl. ¶¶21-22).
• Technical Importance: This technology allows a server to efficiently initiate communication with a specific application on a mobile device, enabling features like real-time alerts and data updates without requiring the device to maintain a constant, power-draining connection to the server (Compl. ¶23).

Key Claims at a Glance

• The complaint asserts independent claim 1 (Compl. ¶57).
• Essential elements of independent claim 1 (a method for use on a mobile handset) include:
  • receiving a first communication initiated by a remote entity, which includes information identifying an application layer program
  • evaluating the set of information
  • in response, launching the identified application layer program
  • reactivating, from an inactive state, a communication session between the mobile handset and the remote entity
• The complaint reserves the right to assert other claims (Compl. ¶59).

U.S. Patent No. 8,291,010 - "VIRTUAL CONNECTION OF A REMOTE UNIT TO A SERVER" (issued October 16, 2012)

• Technology Synopsis: This patent, from the same family as the ’239 and ’296 patents, also describes a system for maintaining a "virtual session" to provide a seamless connection experience over intermittent physical links (’010 Patent, Abstract). It details methods where a communication session can be placed into an inactive state and later resumed by either the remote unit or the server, using stored session parameters to accelerate the reconnection process and support an application program (’010 Patent, col. 3:44-51, FIG. 5).
• Asserted Claims: Independent claims 1 and 17 (Compl. ¶¶75-76).
• Accused Features: The accused features are the KW App's functions for establishing and resuming client-server connections and its use of push notifications to deliver data from Keller Williams' servers to the user's mobile device (Compl. ¶¶72, 74).

III. The Accused Instrumentality

Product Identification

The "KW: Buy & Sell Real Estate App," referred to as the "KW App" (Compl. ¶36).

Functionality and Market Context

The complaint alleges that the KW App communicates with Defendant's remote servers to provide real estate services to users (Compl. ¶23). The relevant technical functionality involves the use of Transport Layer Security (TLS) sessions for two purposes: first, for receiving wireless push notification messages sent from the server, and second, for establishing separate connections for traditional client-server communications, such as when the app actively requests data (Compl. ¶¶38, 56, 74). The complaint alleges that this system allows Defendant's servers to send information to the app even when it is not in the foreground, enhancing customer engagement and operational efficiency (Compl. ¶23).

No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint references, but does not include, claim chart exhibits detailing its infringement theories. The narrative infringement allegations are summarized below.

'239 Patent Infringement Allegations

The complaint's narrative theory for infringement of claim 7 alleges that Defendant’s servers, in communication with a mobile device running the KW App, perform the patented method (Compl. ¶¶38, 39). The theory appears to map the server-initiated sending of a push notification to the claim limitation of "dialing a telephone number" and the data within that notification to the claimed "application-program identifying packet" (Compl. ¶38; ’239 Patent, claims 6-7). This server-initiated communication is alleged to cause the reactivation of a "virtual session" between the server and the app, which had previously been placed in an "inactive state" (Compl. ¶38).

'296 Patent Infringement Allegations

The complaint's narrative theory for infringement of claim 1 alleges that the mobile device operating the KW App performs the patented method (Compl. ¶¶56, 57). The theory posits that a "control program" on the device receives an unsolicited push notification from Defendant’s servers (the "remote entity") (Compl. ¶56). This notification allegedly contains information identifying the KW App. It is alleged that the device then evaluates this information, launches the KW App from an inactive state, and reactivates a communication session with the server to process the notification's data (Compl. ¶¶56, 57).

Identified Points of Contention

• Scope Questions: The infringement analysis for the ’239 Patent may raise the question of whether patent terms rooted in 1990s dial-up technology (e.g., "dialing a telephone number," "caller identification") can be construed to read on modern IP-based push notification systems. The analysis for the ’296 Patent may raise the question of whether the "control program" that receives the initial communication refers to the KW App itself or to the mobile device's operating system, which typically handles incoming network packets before routing them to a specific application.
• Technical Questions: A central technical question for the ’239 Patent allegations is what evidence shows that the server-initiated push notification performs the claimed function of "placing the virtual session back into the active state," as opposed to the mobile OS performing that function in response to the notification. For the ’296 Patent, a key question is what specific "set of information" within the accused push notification allegedly identifies the KW App, and how the accused "control program" evaluates it as required by the claim.

V. Key Claim Terms for Construction

Term: "dialing a telephone number" (’239 Patent, claim 1)

• Context and Importance: Practitioners may focus on this term because the patent family originates in the dial-up modem era, while the accused technology involves modern IP packet addressing. The viability of the infringement claim may depend on construing this term broadly enough to cover the sending of a data packet to a device's IP address or push notification token.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The specification discusses the invention's utility for "wireless applications" and "wireless Internet devices," which could suggest an intended scope beyond literal telephony (’239 Patent, col. 4:6-12). It also describes a server sending a "message" that "identify[s] the relevant client-side application program (App)," a concept that aligns more with data networking than traditional dialing (’239 Patent, col. 9:61-64).
  • Evidence for a Narrower Interpretation: The plain meaning of the term is tied to telephony. The specification provides explicit examples involving "audio modem tones and hissing sounds" and includes a flowchart with a step for "DIAL-OUT TO REMOTE UNIT," which may support a narrower construction limited to circuit-switched telephone networks (’239 Patent, col. 4:24-30, Fig. 7).

Term: "a control program executing on a mobile handset" (’296 Patent, claim 1)

• Context and Importance: Practitioners may focus on this term because its definition determines the locus of the infringing act of "receiving" the initial communication. The infringement case may depend on whether this term can encompass a mobile operating system's generalized networking and notification services, or if it is limited to the specific, accused KW App itself.
• Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The patent’s block diagrams depict the "CONTROL PROGRAM MODULE" as a fundamental component of the remote unit's architecture, distinct from specific application sessions, which could support its interpretation as an OS-level or system-level service that manages communications (’296 Patent, Fig. 1, element 120).
  • Evidence for a Narrower Interpretation: The specification links the "application program" with the "control program" by stating, "The application program is operative to supply a sequence of interactive screens... implemented in the control program 120," which could be used to argue that the two are integrated and the term refers to the user-facing application, not a background OS process (’296 Patent, col. 7:21-24).

VI. Other Allegations

The complaint does not contain allegations of indirect or willful infringement.

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

The resolution of this dispute, which seeks damages for infringement of expired patents, will likely depend on the court's determination of two central issues:

• A core issue will be one of definitional scope: can terminology originating in the context of 1990s dial-up modems, such as "dialing a telephone number," be construed to cover the addressing and transmission methods of modern, IP-based push notification services?
• A key evidentiary question will be one of functional locus: does the evidence show that Defendant’s server performs the session reactivation as claimed in the ’239 patent, or does the mobile device’s OS perform that step? Likewise, does the KW App itself, or an underlying OS service, perform the initial "receiving" and "evaluating" steps required by the ’296 patent?