DCT
3:22-cv-04552
Google LLC v. Sonos Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Google LLC (California)
- Defendant: Sonos, Inc. (Delaware)
- Plaintiff’s Counsel: Quinn Emanuel Urquhart & Sullivan, LLP
- Case Identification: 3:22-cv-04552, N.D. Cal., 08/08/2022
- Venue Allegations: Plaintiff alleges venue is proper in the Northern District of California because Defendant Sonos maintains a regular and established place of business in the district and has allegedly committed acts of patent infringement there.
- Core Dispute: Plaintiff alleges that Defendant’s smart speakers and related voice-controlled and portable products infringe three Google patents related to multi-device hotword detection and wireless charging management.
- Technical Context: The lawsuit concerns core technologies in the highly competitive smart home and portable audio markets, specifically how multiple voice-activated devices arbitrate responses and how devices manage power from multiple charging sources.
- Key Procedural History: The complaint notes a "multi-year partnership" between the parties, during which Google provided significant engineering assistance to Sonos for integrating Google's technologies, including Google Assistant. The complaint also references prior patent lawsuits filed by Sonos against Google, framing this action as a necessary defense of Google's own intellectual property rights.
Case Timeline
| Date | Event |
|---|---|
| 2003-12-31 | '565 Patent Priority Date |
| 2010-04-27 | '565 Patent Issue Date |
| 2014-01-01 | Sonos integrates Google Play Music (approximate) |
| 2014-10-09 | '330 and '398 Patents Priority Date |
| 2018-11-20 | '398 Patent Issue Date |
| 2019-05-01 | Google Assistant launches on Sonos products (approximate) |
| 2020-03-17 | '330 Patent Issue Date |
| 2022-08-08 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 10,593,330 - "Hotword Detection On Multiple Devices"
The Invention Explained
- Problem Addressed: In an environment with multiple speech-enabled devices (e.g., a smart home), a user's spoken hotword could be picked up by several devices simultaneously, causing all of them to respond, which is an undesirable user experience ( '330 Patent, col. 1:49-58).
- The Patented Solution: The invention describes a system where multiple devices in a low-power listening state detect a hotword. They then communicate with each other to arbitrate, allowing only one device—typically the one that "heard" the user best—to exit the low-power mode and respond to the user's command, while the others remain inactive ('330 Patent, Abstract; col. 2:6-21). This coordination prevents a confusing cacophony of responses from multiple devices.
- Technical Importance: This technology is foundational for creating a seamless and intelligent multi-device voice assistant ecosystem, a key feature in the modern smart home market (Compl. ¶5:17-23).
Key Claims at a Glance
- The complaint asserts independent claims 1 and 9 ('330 Patent, Compl. ¶24).
- Independent Claim 1 (a method) includes the elements of:
- A computing device in a low power mode receiving audio data for a predefined hotword.
- While remaining in the low power mode, transmitting a message and receiving an additional message from another computing device.
- Based on both messages, determining whether to exit the low power mode.
- Independent Claim 9 covers a system configured to perform the method of claim 1.
- The complaint reserves the right to assert other claims, including dependent claims 2-7, 10-15, and independent claim 17 (Compl. ¶24).
U.S. Patent No. 10,134,398 - "Hotword Detection On Multiple Devices"
The Invention Explained
- Problem Addressed: Similar to the '330 patent, the technology addresses the problem of multiple devices in close proximity all responding to a single voice command, which would be inefficient and confusing for the user ('398 Patent, col. 1:49-58).
- The Patented Solution: The patent describes a method where each device that detects an utterance computes a "hotword confidence score"—a value representing the likelihood that the utterance contained the hotword. The devices share these scores, compare them, and the device with the highest score proceeds to initiate speech recognition, while the others stand down ('398 Patent, Abstract; col. 2:6-21). The system is illustrated with a diagram showing a user speaking to a phone, tablet, and thermostat, which then exchange scores to determine which one should respond ('398 Patent, FIG. 1).
- Technical Importance: The use of a confidence score provides a quantitative and robust method for arbitrating between devices, improving the reliability of voice control in complex acoustic environments (Compl. ¶5:17-21).
Key Claims at a Glance
- The complaint asserts independent claims 1, 9, and 16 ('398 Patent, Compl. ¶35).
- Independent Claim 1 (a method) includes the elements of:
- Receiving audio data corresponding to an utterance.
- Determining a first value corresponding to a likelihood that the utterance includes a hotword.
- Receiving a second, similar value from a second computing device.
- Comparing the first and second values.
- Based on the comparison, initiating speech recognition processing on the audio data.
- The complaint reserves the right to assert other claims, including dependent claims 2-5, 7-8, 10-13, 15, and 17-20 (Compl. ¶35).
U.S. Patent No. 7,705,565 - "Method and System for Wireless Charging"
- Technology Synopsis: The patent addresses a technical problem arising when a portable device can be charged simultaneously by a wireless charger and a conventional wired charger. To prevent potential damage from excess current, the invention provides a method for the battery itself to sense the charging current and signal the host electronic device, which can then take protective action, such as disabling its own internal charging circuit ('565 Patent, Abstract; col. 1:26-34).
- Asserted Claims: Independent claims 1, 9, and 18 are asserted (Compl. ¶46).
- Accused Features: The complaint accuses Sonos products like the Move and Roam, which support both wired (USB-C) and wireless (Qi) charging, of using this patented technology to manage power from both sources (Compl. ¶46; ¶11:1-11).
III. The Accused Instrumentality
Product Identification
- "Accused Voice Products" (for the '330 and '398 patents): Sonos products that support the "Sonos Voice Control" feature, including the Sonos One, Sonos Move, Sonos Roam, Sonos Arc, and Sonos Beam (Compl. ¶18).
- "Accused Portable Products" (for the '565 patent): Sonos audio players that support both wired and wireless charging, including the Sonos Move, Sonos Roam, and Sonos Roam SL (Compl. ¶46).
Functionality and Market Context
- The complaint alleges that the Accused Voice Products use "hotwords" to enable a "power-efficient" voice control experience, which is described as a "commercially-desirable" feature (Compl. ¶11:1-4).
- The Accused Portable Products are alleged to manage battery charging from both wired and wireless sources (Compl. ¶11:3-4, ¶11:1-6).
- The complaint contends these software-driven features are "fundamental" to the products' operation and quotes Sonos's own statements that "the magic of the system is the software" (Compl. ¶12:7-9, ¶12:21-22).
IV. Analysis of Infringement Allegations
No probative visual evidence provided in complaint.
The complaint alleges infringement but does not provide claim charts, which are attached as exhibits not available for this analysis. The following charts are based on the infringement theories articulated in the complaint.
'330 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A computer-implemented method comprising: receiving, by a computing device that is in a low power mode..., audio data that corresponds to an utterance of a particular, predefined hotword... | The accused Sonos speakers allegedly operate in a power-efficient mode and are equipped with microphones to receive user speech, including hotwords for "Sonos Voice Control." | ¶11:2-3; ¶17 | col. 15:1-12 |
| ...transmitting, by the computing device..., a message; | The complaint's theory requires that multiple Sonos devices "work together," which suggests they transmit messages to coordinate hotword responses. | ¶12:7-9 | col. 15:13-15 |
| ...receiving, by the computing device and from an additional computing device..., an additional message; and | To arbitrate which device responds, the accused Sonos devices allegedly receive messages from other Sonos devices that also heard the hotword. | ¶12:7-9 | col. 15:16-19 |
| based on the message and the additional message, determining, by the computing device, to exit the low power mode. | Based on the exchange of messages, only one accused Sonos device allegedly becomes fully active to process the command, while others remain in a lower power state. | ¶11:2-3 | col. 15:20-22 |
'398 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method comprising: receiving, by a first computing device, audio data that corresponds to an utterance; | Accused Sonos speakers contain microphones that receive audio data from a user's spoken commands. | ¶17 | col. 7:24-26 |
| determining a first value corresponding to a likelihood that the utterance includes a hotword; | The "Sonos Voice Control" feature allegedly processes the audio to determine a likelihood that a hotword was spoken. | ¶11:2-3 | col. 7:27-29 |
| receiving a second value corresponding to a likelihood that the utterance includes the hotword, the second value being determined by a second computing device; | The infringement theory requires that multiple accused Sonos speakers exchange data to arbitrate a response. | ¶12:7-9 | col. 7:30-33 |
| comparing the first value and the second value; and | The accused system allegedly compares the likelihood values from different devices to decide which one should respond. | ¶12:7-9 | col. 7:34 |
| based on comparing the first value to the second value, initiating speech recognition processing on the audio data. | The accused Sonos device that determines it has the highest likelihood value allegedly proceeds to fully process the user's voice command. | ¶11:2-3 | col. 7:35-37 |
- Identified Points of Contention:
- Technical Questions: A primary question for both the '330 and '398 patents is what technical mechanism the "Sonos Voice Control" feature actually uses for arbitration. The complaint does not specify how the accused system works, only that it infringes. The case may turn on whether Sonos's system computes and compares "likelihood" values as claimed, or if it uses a different, potentially non-infringing method (e.g., based on which device first detected the hotword, or which detected the loudest signal).
- Scope Questions: For the '330 patent, a key dispute may arise over the definition of "low power mode." The infringement analysis will depend on whether this term is construed broadly to cover any state of reduced power consumption or is limited to a more specific "sleep" state as depicted in the patent's embodiments.
V. Key Claim Terms for Construction
The Term: "low power mode" ('330 Patent, Claim 1)
Context and Importance: This term is a central limitation in independent claim 1 of the '330 patent, which requires that the transmitting and receiving steps occur while the device remains in this state. The viability of the infringement claim hinges on whether the normal listening state of the accused Sonos products qualifies as a "low power mode" under the patent's definition.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification does not appear to provide a narrow, explicit definition of the term, which may support an argument that it should be given its plain and ordinary meaning, covering any operational state with reduced power consumption compared to a fully active state.
- Evidence for a Narrower Interpretation: The patent figures and their description explicitly show devices with a "Device Status" of "Sleep" ('330 Patent, FIG. 1; col. 6:40-45). A party may argue that "low power mode" should be construed as being limited to this specifically disclosed "sleep" state.
The Term: "a value corresponding to a likelihood that the utterance includes a hotword" ('398 Patent, Claim 1)
Context and Importance: This term defines the specific type of data that devices are required to generate and exchange to arbitrate responses. Practitioners may focus on this term because the infringement determination will depend on whether the data exchanged between accused Sonos devices is, in fact, a "likelihood" value, as opposed to a simpler binary signal or a different type of metric.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The claim uses the general term "value," which could be argued to encompass any data point, including non-numeric signals, that functionally indicates a likelihood.
- Evidence for a Narrower Interpretation: The specification consistently refers to this value as a "hotword confidence score" and provides specific numerical examples (e.g., "0.85," "0.6," and "0.45"), suggesting a quantitative, scaled metric ('398 Patent, col. 5:25-28). A party could argue that the term requires such a numerical confidence score.
VI. Other Allegations
- Indirect Infringement: The complaint alleges both induced and contributory infringement for all three patents. The inducement allegations are based on Sonos allegedly encouraging and instructing end-users on how to use the infringing features through promotional materials and user guides (Compl. ¶27, ¶38, ¶49).
- Willful Infringement: The complaint alleges that Sonos's infringement is willful and deliberate. The stated basis for knowledge is "by no later than the filing of this action," which grounds the willfulness claim in post-suit conduct (Compl. ¶25, ¶29, ¶36, ¶40, ¶47, ¶51). The complaint does not explicitly allege that Sonos had knowledge of the patents before the lawsuit was filed.
VII. Analyst’s Conclusion: Key Questions for the Case
- Arbitration Mechanism: A central factual question for the '330 and '398 patents will be one of technical implementation: Does the accused Sonos Voice Control system arbitrate responses by computing and exchanging "likelihood" values or "confidence scores" as the claims require, or does it employ a technically distinct, non-infringing method for selecting a single device to respond?
- Claim Construction: A key legal question will concern definitional scope: Can the term "low power mode" in the '330 patent be broadly construed to cover the standard listening state of the accused Sonos speakers, or will it be narrowed to a more specific "sleep" state, potentially creating a significant hurdle for the infringement claim?
- Functional Operation: For the '565 patent, a dispositive evidentiary question will be one of functional causality: Does the accused charging system perform the specific sequence of sensing a charging current and, in response, signaling the device to disable a second charging circuit as claimed, or is the management of dual power sources achieved through a different operational logic?