Linkplay Technology Inc v. Sonos Inc

1. Case Identification

• Case #: IPR2025-00510
• Patent #: 10541883
• Filed: February 5, 2025
• Petitioner(s): Linkplay Technology Inc.
• Patent Owner(s): Sonos, Inc.
• Challenged Claims: 1-20

2. Patent Overview

• Title: Method and Apparatus for Setting Up and Configuring a Device in a Wireless Local Area Network
• Brief Description: The ’883 patent describes a process for configuring a new playback device to join a secure wireless local area network (WLAN). The process involves using a computing device already on the network to establish a temporary, direct communication path with the new device to transfer the necessary network configuration parameters (e.g., SSID and security key).

3. Grounds for Unpatentability

Ground 1: Anticipation and/or Obviousness over Rector - Claims 1-8, 10-12, and 14-20 are anticipated by or obvious over Rector.

• Prior Art Relied Upon: Rector (Application # US2003/0212802).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued Rector discloses a nearly identical system for adding a new network device to an existing WLAN. Rector’s “network device 112,” which can be an audio playback device, corresponds to the claimed “playback device.” Rector’s “proximity setup component 108” is a computing device already on the WLAN defined by a “gateway component 106” (access point). The setup process is triggered when the user brings the new device into proximity of the setup component. A temporary, separate “network connection 202” (e.g., infrared or Bluetooth) is established, which serves as the “initial communication path” that does not traverse the access point. Over this path, the setup component transmits network configuration data, such as the SSID and encryption key, to the new device, which then uses that data to connect to the main WLAN and transition away from the temporary path.
  • Motivation to Combine (for §103 grounds): Not applicable for anticipation. For obviousness, Petitioner asserted that any minor differences would be obvious modifications to a person of ordinary skill in the art (POSITA) as Rector teaches all core elements of the claimed setup process.
  • Expectation of Success (for §103 grounds): A POSITA would have an expectation of success as implementing Rector’s setup method would predictably result in a functional network connection for the new device.

Ground 2: Anticipation and/or Obviousness over Gassho - Claims 1-8, 12, and 14-20 are anticipated by or obvious over Gassho.

• Prior Art Relied Upon: Gassho (Application # US2003/0092395).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner contended Gassho discloses the claimed invention, describing a method for setting up a new wireless device (e.g., a print server, but also applicable to cell phones) on an existing WLAN. Gassho’s “station ST1” is a computing device on a WLAN defined by an access point “AP1.” The new device, a “radio print server (PS),” enters a setup mode and sends a “setting requirement signal.” In response, ST1 establishes a “direct communication” link (the initial communication path) that does not traverse the access point. ST1 then transmits the WLAN setting parameters (ESS-ID and WEP key) to the PS, which uses them to connect to the main WLAN. Gassho also discloses the PS sending a response message to confirm receipt of the parameters before transitioning to standard communication on the WLAN.
  • Motivation to Combine (for §103 grounds): For obviousness, Petitioner argued that even if Gassho’s primary example is a printer, it explicitly states the technique is applicable to other devices like cell phones. A POSITA would find it obvious to apply Gassho's well-defined setup process to an audio playback device to solve the known problem of configuring devices that lack a user interface.
  • Expectation of Success (for §103 grounds): A POSITA would expect success because Gassho’s method is a standard technique for securely transferring network credentials and is not specific to the type of end device.

Ground 3: Obviousness over Spurgat in view of Gassho - Claims 1-20 are obvious over Spurgat in view of Gassho.

• Prior Art Relied Upon: Spurgat (Application # US2002/0174243) and Gassho (Application # US2003/0092395).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued Spurgat discloses a digital audio communication system with multiple digital audio players communicating on a WLAN via an access point, controlled by a computing platform. Spurgat discloses the importance of device discovery and synchronization but does not explicitly detail the initial network setup process. Gassho remedies this deficiency by providing a detailed, secure method for adding a new wireless device to a WLAN.
  • Motivation to Combine (for §103 grounds): A POSITA would combine Spurgat with Gassho to provide a complete, functional system. Spurgat identifies the need for device discovery and connection, and Gassho provides the well-known solution for that exact problem: securely configuring a new device for a wireless network. The combination addresses the purported problem of the ’883 patent by applying Gassho’s setup procedure to Spurgat’s audio players.
  • Expectation of Success (for §103 grounds): A POSITA would have a high expectation of success because Gassho’s setup process is designed for generic wireless devices and would predictably work with Spurgat’s audio players without requiring any undue experimentation.

• Additional Grounds: Petitioner asserted an additional obviousness challenge against claims 3, 7-11, 13, and 19 based on Rector in view of Richenstein (Application # US2003/0083024), arguing Richenstein taught post-setup features (e.g., controlling synchronized playback, forming groups) that a POSITA would be motivated to add to Rector's networked audio devices.

4. Arguments Regarding Discretionary Denial

• Petitioner argued against discretionary denial under 35 U.S.C. §325(d), contending that the primary references Gassho and Richenstein were never presented to or considered by the examiner during prosecution. While Rector and Spurgat were cited in an Information Disclosure Statement (IDS), the examiner materially erred by overlooking their direct relevance, particularly Rector's near-complete anticipation of the claims.
• Petitioner further argued against discretionary denial under Fintiv (§314(a)), asserting that the co-pending district court trial is scheduled for May 2026, well after the August 2026 deadline for a Final Written Decision (FWD), and there is significant uncertainty around the trial date. Investment in the litigation has been minimal, and the petition was filed promptly after the patent owner identified the asserted claims.

5. Relief Requested

• Petitioner requests institution of an inter partes review (IPR) and cancellation of claims 1-20 of the ’883 patent as unpatentable.