DCT

2:25-cv-00757

Cerence Operating Co v. Sony Group Corp

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:25-cv-00757, E.D. Tex., 08/01/2025
  • Venue Allegations: Plaintiff alleges venue is proper for Sony Group Corporation because it is not a resident of the United States. For the other Sony entities, venue is alleged based on their registration to do business in Texas and their regular and established places of business within the Eastern District of Texas.
  • Core Dispute: Plaintiff alleges that Defendant’s smart televisions infringe four patents related to user interface navigation, audio processing, microphone signal processing, and natural language voice services.
  • Technical Context: The technologies at issue relate to user interaction with complex electronic devices, particularly in the areas of voice command processing, audio fidelity, and information retrieval.
  • Key Procedural History: The complaint notes that Plaintiff Cerence was spun out from Nuance Communications, Inc. in October 2019, positioning it as a public company focused on conversational AI tools, primarily in the automotive market. No other significant procedural events are mentioned.

Case Timeline

Date Event
2004-11-12 ’810 Patent Earliest Priority Date
2004-12-14 ’598 Patent Earliest Priority Date
2005-12-12 ’579 Patent Earliest Priority Date
2009-11-10 ’541 Patent Earliest Priority Date
2010-11-23 ’579 Patent Issue Date
2011-02-22 ’598 Patent Issue Date
2012-05-29 ’810 Patent Issue Date
2015-10-27 ’541 Patent Issue Date
2019-10 Cerence becomes a separate public company
2025-08-01 Complaint Filing Date

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

U.S. Patent No. 7,840,579 - "Mobile Device Retrieval and Navigation," Issued November 23, 2010

The Invention Explained

  • Problem Addressed: The patent describes the challenge of users accessing large amounts of information on devices with ambiguous input systems, such as wireless phones with reduced-size keyboards where a single key represents multiple characters (Compl. ¶25; ’579 Patent, col. 5:1-13).
  • The Patented Solution: The invention proposes a method to refine searches by allowing a user to enter a first input (a "first stem"), followed by a "separator," and then a second input (a "second stem"). The system then relates both stems to a library of candidates to render a more specific set of results, reducing the effort required to find the desired information (Compl. ¶25; ’579 Patent, Abstract; col. 6:45-65). For example, a user could search for a two-word term more efficiently by entering a portion of each word separated by a designated character.
  • Technical Importance: This multi-stem input method aimed to improve the usability of early mobile devices by making search and navigation more efficient with limited and often ambiguous input hardware (Compl. ¶18, ¶22; ’579 Patent, col. 5:1-13).

Key Claims at a Glance

  • The complaint asserts the independent claims of the patent (Compl. ¶27). Independent claim 1 includes the following essential elements:
    • receiving a first input from a user;
    • structuring the first input as a first stem;
    • receiving a separator designating subsequently-received input as a second input;
    • receiving the second input;
    • structuring the second input as a second stem;
    • relating the first and second stems to a library of candidates by identifying matches; and
    • rendering one or more results in response.

U.S. Patent No. 7,894,598 - "System for Limiting Received Audio," Issued February 22, 2011

The Invention Explained

  • Problem Addressed: The patent addresses acoustic echo in communication systems like speakerphones. When audio played from a loudspeaker is too loud, the signal picked up by a nearby microphone can be "clipped," introducing non-linear distortion that prevents echo cancellation systems from working effectively (Compl. ¶32; ’598 Patent, col. 1:40-54).
  • The Patented Solution: The invention is a system that predicts the audio power that will reach the microphone before the sound is played. It uses an "echo power estimator" to model the audio path and, if the estimated power exceeds a clipping threshold, a "limiter" reduces the signal's volume before it is sent to the loudspeaker. This preemptive limiting ensures the signal at the microphone remains in the linear range, allowing for accurate echo cancellation (Compl. ¶32; ’598 Patent, Abstract; col. 2:20-28).
  • Technical Importance: This technology was aimed at improving the audio quality and reliability of hands-free communication systems, particularly in environments where the speaker and microphone are in close proximity (Compl. ¶32; ’598 Patent, col. 1:9-14).

Key Claims at a Glance

  • The complaint asserts the independent claims of the patent (Compl. ¶34). Independent claim 1 includes the following essential elements:
    • An echo power estimator for estimating audio power received at the microphone when an output signal is reproduced by the speaker; and
    • A limiter adapted to limit the output signal to the speaker when the estimated audio power exceeds a threshold.

Multi-Patent Capsule: U.S. Patent No. 8,819,810 - "System for Processing Microphone Signals to Provide an Output Signal with Reduced Interference," Issued May 29, 2012

  • Technology Synopsis: The complaint identifies the '810 Patent by this title (Compl. ¶39). However, the patent itself is titled "Password Resetting Method" and is directed to a system for automatically selecting a password reset procedure. The selection is based on factors such as the value of the user data being protected and the statistical likelihood of the user forgetting the password, aiming to balance security with user convenience ('810 Patent, Abstract).
  • Asserted Claims: The complaint asserts the independent claims of the patent (Compl. ¶41).
  • Accused Features: The complaint accuses Sony's smart televisions, such as the exemplary BRAVIA model, of infringement (Compl. ¶40).

Multi-Patent Capsule: U.S. Patent No. 9,171,541 - "System and Method for Hybrid Processing in a Natural Language Voice Services Environment," Issued October 27, 2015

  • Technology Synopsis: The patent describes a system for processing natural language requests in an environment with multiple, interconnected devices. A central "virtual router" receives input, which can include audio from multiple devices that heard the same utterance. The router can select the "cleanest" audio sample and coordinate among the various devices and servers in the network to determine the user's intent and resolve the request ('541 Patent, Abstract).
  • Asserted Claims: The complaint asserts the independent claims of the patent (Compl. ¶48).
  • Accused Features: The complaint alleges that the voice command and smart features of Sony's televisions infringe the '541 Patent (Compl. ¶47).

III. The Accused Instrumentality

Product Identification

  • The complaint identifies the Accused Products as "televisions with smart features and functionality," with the "Sony BRAVIA 8 II 65” Class QD-OLED 4K HDR – K-65XR80M2" cited as an exemplary product (Compl. ¶1, ¶26).

Functionality and Market Context

  • The complaint alleges the Accused Products incorporate conversational AI and voice control features that allow users to interact with the television and other connected devices (Compl. ¶22).
  • Functionality cited in support of infringement allegations includes voice search functions, hands-free voice search using a built-in microphone, and the use of a voice assistant to find content, control the TV, and manage smart home devices like lighting and thermostats (Compl. ¶35 n.1, ¶42 n.2, ¶49 n.3).
  • The complaint positions these features as part of a market trend expanding automotive assistant technology into home entertainment systems (Compl. ¶22).

IV. Analysis of Infringement Allegations

The complaint references, but does not include, claim chart exhibits detailing its infringement theories (Compl. ¶27, ¶34). The infringement allegations for the lead patents are summarized below based on the complaint's narrative.

The infringement theory for the ’579 Patent appears to center on the allegation that when a user enters a search query into a Sony smart TV, the system receives and structures that input into searchable terms ("stems") and relates them to a library of available content and applications to generate results (Compl. ¶26). This process is alleged to meet the elements of the patent's claims for multi-stem retrieval and navigation.

For the ’598 Patent, the infringement theory appears to be that the audio processing systems in the Accused Products, particularly for features involving voice commands, practice the claimed invention. The complaint alleges these systems estimate the power of audio signals before outputting them through the speakers and limit that power to prevent clipping or distortion at the built-in microphone, thereby enabling effective echo cancellation (Compl. ¶33).

  • Identified Points of Contention:
    • Scope Questions: The infringement analysis for the ’579 Patent may raise the question of whether the patent’s claims, described in the context of "mobile device[s]" with "reduced-size keyboards," can be construed to cover modern, stationary smart televisions with voice and full-text input capabilities ('579 Patent, col. 5:1-13).
    • Technical Questions: For the ’598 Patent, a central question will be whether the Accused Products' audio processing functionality performs the specific "estimat[ing]" and "limit[ing]" steps as required by the claims. The analysis will depend on evidence of how Sony's audio hardware and software actually operate, as compared to the architecture described in the patent, which details a system using a low-order IIR filter derived from an echo cancellation filter ('598 Patent, col. 4:50-54).
    • Pleading Questions: Regarding the '810 Patent, a threshold issue may arise from the discrepancy between the complaint's description of the patent's technology (microphone signal processing) and the patent's actual subject matter (password resetting) (Compl. ¶39; ’810 Patent, Abstract).

No probative visual evidence provided in complaint.

V. Key Claim Terms for Construction

  • Patent: U.S. Patent No. 7,840,579

    • The Term: "separator"
    • Context and Importance: This term is fundamental to the claimed method of distinguishing a "first stem" from a "second stem." The viability of the infringement allegation depends on identifying a corresponding "separator" functionality in the accused TVs. Practitioners may focus on this term because its definition could determine whether a simple space in a text search or a pause in a voice command meets the claim limitation.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The specification suggests a separator can be received "in response to determining that the user has selected a different entry mode," such as switching from voice to keypad input, implying it need not be an explicit character ('579 Patent, col. 2:9-14).
      • Evidence for a Narrower Interpretation: Many embodiments describe the separator as an explicit user input on a reduced-entry keypad, such as a "#" key, which could support a narrower construction limited to discrete, designated inputs ('579 Patent, col. 6:2-3).

  • Patent: U.S. Patent No. 7,894,598

    • The Term: "echo power estimator"
    • Context and Importance: This is the core predictive element of the invention; infringement requires showing the accused system does more than just generic audio compression or limiting. The construction of this term will define what technical architecture is required to infringe.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The claim language is functional, defining the element by what it does: "estimating audio power received at the microphone." This could support a construction that covers any component performing this function, regardless of its specific implementation.
      • Evidence for a Narrower Interpretation: The detailed description discloses a specific structure for implementing the estimator: a "low order infinite impulse response (IIR) filter" whose coefficients are derived from an adaptive echo cancellation filter ('598 Patent, col. 4:50-54). A defendant may argue that the claims should be understood in light of this specific embodiment.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges induced infringement for all four patents, asserting that Sony, with knowledge of the patents, encourages infringement by its customers (Compl. ¶28, ¶35, ¶42, ¶49). As evidence of intent, the complaint cites Sony's online support articles and product marketing materials, which allegedly instruct users on how to use the infringing voice features (Compl. ¶35 n.1, ¶42 n.2, ¶49 n.3). The complaint also alleges contributory infringement, stating the Accused Products are not staple articles of commerce suitable for substantial noninfringing use (Compl. ¶29, ¶36, ¶43, ¶50).
  • Willful Infringement: Willfulness is alleged for all four patents. The basis for willfulness appears to be knowledge of the patents and the alleged infringement as of at least the filing date of the complaint (Compl. ¶30, ¶37, ¶44, ¶51).

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

  1. A core issue will be one of technological scope and applicability: Can the claims of patents like the '579 Patent, which are rooted in the technical problems and hardware limitations of early 2000s mobile phones, be properly construed to read on the fundamentally different user interface and hardware environment of a modern smart television?
  2. A key evidentiary question will be one of functional implementation: Does the complaint provide sufficient factual basis to suggest that Sony's audio processing architecture performs the specific predictive estimation claimed in the ’598 patent, or will discovery reveal a system that uses a distinct, non-infringing method for managing audio and echo?
  3. A threshold procedural question for the '810 patent will be the discrepancy in the complaint's pleadings: How will the parties and the court address the fact that the complaint's narrative alleges infringement of a patent on microphone signal processing, while the actual asserted '810 patent relates to a method for password resetting?