PTAB

IPR2019-00412

ZTE USA Inc v. Seven Networks LLC

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Method for power saving in mobile devices by optimizing wakelocks
  • Brief Description: The ’254 patent describes methods for conserving battery power in mobile devices by managing "wakelocks," which are software mechanisms that prevent a device from entering a low-power sleep state. The invention uses an application's status on a "whitelist" and the device's activity state to determine when to acquire or release system wakelocks.

3. Grounds for Unpatentability

Ground 1: Claims 1, 2, 4, and 9 are obvious over WakeScope and Sony.

  • Prior Art Relied Upon: WakeScope (a 2013 paper on a runtime wakelock anomaly management scheme for Android) and Sony (a 2013 blog post describing Sony's "Battery STAMINA Mode").
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that WakeScope, a system for detecting and handling "wakelock anomalies," discloses the core limitations of independent claim 1. This includes a mobile device detecting its activity state based on the display screen status (e.g., screen off) and entering a power optimization (sleep) state. WakeScope also teaches acquiring a "system wakelock" at the kernel level in response to an application's request. To meet the limitations concerning a "whitelist," Petitioner relied on Sony, which discloses a "Battery STAMINA Mode" that reduces background activities when the screen is off. Sony explicitly teaches using a user-configurable whitelist to allow "important applications" to continue running in the background while non-whitelisted apps are restricted to conserve power.
    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine the teachings of Sony with WakeScope to improve WakeScope's power management system. WakeScope's approach of killing an application or forcing the device to sleep upon detecting a wakelock anomaly could be indiscriminate. A POSITA would integrate Sony's whitelist feature to allow users to specify critical applications that should not be restricted, thereby preventing unwanted interruptions for important background tasks while still saving power from non-critical applications. This combination would yield the predictable result of a more refined and user-friendly power-saving tool.
    • Expectation of Success: A POSITA would have a reasonable expectation of success in this combination, as it involves integrating a known software feature (whitelisting) into a known power management framework to achieve the predictable benefit of user-customizable power optimization.

Ground 2: Claims 3, 6-8, 10, 11, 13-15, 28, 29, and 31-33 are obvious over WakeScope, Sony, and Srinivasan.

  • Prior Art Relied Upon: WakeScope, Sony, and Srinivasan (Application # 2014/0038674).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground builds on the WakeScope and Sony combination to address claims requiring the activity state to be based on motion sensing. While WakeScope and Sony provide the foundational power optimization and whitelisting framework, Srinivasan provides the missing element. Srinivasan teaches an activity recognition system for mobile devices that uses motion sensors, such as an accelerometer and gyroscope, to determine a user's activity (e.g., idle, walking, running). Based on the detected activity, Srinivasan’s system dynamically controls power consumption and can transition the device into a sleep mode if the user is determined to be idle.
    • Motivation to Combine: A POSITA would be motivated to incorporate Srinivasan's motion-based activity detection into the WakeScope/Sony system to enhance its accuracy. Relying solely on screen status or keystrokes to determine user inactivity is imperfect; a user could be physically active (e.g., running with the phone in their pocket) without interacting with the screen. Adding motion detection as taught by Srinivasan would provide a more reliable indication of the user's true activity state, preventing the device from entering a power optimization state inappropriately and thus improving the overall user experience.
    • Expectation of Success: Combining sensor data to create more context-aware systems was a common and well-understood practice in mobile device development. A POSITA would have reasonably expected to successfully integrate motion-sensing logic from Srinivasan into the power management system of WakeScope/Sony.

  • Additional Grounds: Petitioner asserted two additional grounds. Ground 2 argued claim 5 is obvious over WakeScope, Sony, and Marcellino (Application # 2010/0216434), where Marcellino was used to teach the common-sense principle of disabling power-saving modes when a device is connected to an external power source. Ground 4 argued claims 12 and 30 are obvious over the combination of all four references (WakeScope, Sony, Srinivasan, and Marcellino) for claims that depend on limitations taught by both Srinivasan and Marcellino.

4. Arguments Regarding Discretionary Denial

  • Petitioner requested joinder with an already-instituted inter partes review, IPR2018-01117 (the "Google IPR"), which challenged the same patent. Petitioner filed its petition concurrently with a Motion for Joinder, arguing that joining the proceeding would promote efficiency and avoid duplicative efforts and the risk of inconsistent outcomes.

5. Relief Requested

  • Petitioner requests institution of an IPR and cancellation of claims 1-15 and 28-33 of the ’254 patent as unpatentable.