PTAB

IPR2022-00683

Google LLC v. Scramoge Technology Ltd

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Inductive Power Transfer
  • Brief Description: The ’537 patent discloses a system for inductively transferring power from an electrically isolated base unit to a target unit. The system features a control unit in the base unit that monitors a parameter indicative of power transfer efficiency and automatically adjusts the frequency or duty cycle of the current to maximize that efficiency.

3. Grounds for Unpatentability

Ground 1: Claims 1-5, 9-16, 20-22, and 28 are anticipated by Cook.

  • Prior Art Relied Upon: Cook (Patent 8,729,734).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Cook discloses every limitation of the challenged claims. Cook’s “wireless power bridge” system includes a transmit subsystem (base unit) and a receive subsystem (target unit) that are electrically isolated and transfer power via inductive elements (multi-turn loops). Cook’s control subunit monitors the transmit antenna current—a parameter indicative of efficiency—and automatically adjusts the duty cycle and/or frequency of the current from a half-bridge inverter to maximize power transfer efficiency. This control loop is alleged to meet the limitations of independent claims 1, 12, and 28 regarding monitoring a parameter and automatically adjusting a characteristic of the current to maximize efficiency. Dependent claims are met by Cook’s disclosure of adjusting frequency and duty cycle (claims 2, 13), using electronic switches (claims 3, 14), monitoring current at a load circuit (claims 4, 15), comparing to a reference value (claims 5, 16), and adapting to repositioning or substitution of the target unit (claims 9, 10, 20, 21).

Ground 2: Claims 1-5, 9, 10, and 28 are anticipated by Baarman.

  • Prior Art Relied Upon: Baarman (Application # US20040130916A1).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that Baarman independently anticipates the majority of the challenged claims. Baarman’s “adaptive contactless energy transmission system” includes a base power supply and a remote target device. A controller monitors operating parameters, such as the current in the primary winding, via a circuit sensor. Based on whether these parameters are within a nominal range, the controller follows a detailed algorithm to automatically adjust the duty cycle and/or frequency of the current from an inverter to maximize power transfer efficiency. Petitioner contended this system directly maps to the core limitations of the independent claims. Petitioner argued Baarman discloses positioning a remote device in "proximity" to the base unit, satisfying the positioning limitation. Baarman’s explicit algorithmic adjustments for duty cycle and frequency were argued to meet the limitations of various dependent claims.

Ground 3: Claims 1-5, 9-16, 20-22, and 28 are obvious over Baarman in view of Partovi.

  • Prior Art Relied Upon: Baarman (Application # US20040130916A1) and Partovi (Application # 20070182367A1).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground asserted that to the extent Baarman does not explicitly disclose certain features, they are rendered obvious by the combination with Partovi. Specifically, while Baarman teaches an adaptive power transfer system, it may not explicitly disclose a physical “positioning structure” for removably placing the target unit at a predetermined orientation and distance. Partovi, which addresses optimizing inductive power transfer, was cited for its teaching of using physical alignment features, such as magnets, retainers, and complementary shapes on the base and target units, to ensure proper positioning. The combination also addresses the rectifying element required by claim 22, as Partovi teaches using rectifiers to convert induced AC voltage to DC voltage for charging a battery.
    • Motivation to Combine: A POSITA would combine Baarman with Partovi to improve the usability and performance of Baarman’s adaptive system. Proper alignment is a known factor in maximizing inductive charging efficiency, and Partovi provided a known solution (physical positioning structures) to this known problem, which would directly benefit the system disclosed in Baarman.
    • Expectation of Success: A POSITA would have a high expectation of success, as incorporating mechanical or magnetic alignment features as taught by Partovi into an inductive charging system like Baarman’s was a straightforward and well-understood integration of known technologies to achieve a predictable result of improved power transfer efficiency.

  • Additional Grounds: Petitioner asserted that claims 5 and 16 are obvious over Cook in view of Baarman, arguing that if Cook was found not to explicitly teach comparing a measured current to a "constant reference value," Baarman’s teaching of comparing operating parameters to a "nominal range" would have made this feature obvious.

4. Key Claim Construction Positions

  • Petitioner’s analysis relied on claim constructions implied by the Patent Owner’s infringement contentions in co-pending district court litigation.
  • "Parameter indicative of an efficiency of power transfer": Based on the Patent Owner's assertions, Petitioner argued that the "transmit antenna current" as measured in the prior art systems (e.g., by Cook's current sensor) satisfies this limitation.
  • "Load" / "Load Circuit": Consistent with the Patent Owner's contentions, Petitioner argued that an electronic component such as a "current sensing resistor" within a current sensor constitutes a "load" to which the time-varying current is communicated for the purpose of being measured.

5. Arguments Regarding Discretionary Denial

  • Petitioner argued that the Board should not exercise discretionary denial under Fintiv. The co-pending district court litigation was in its early stages, with no trial date set, no claim construction orders issued, and minimal discovery conducted. Petitioner asserted it acted diligently, filing the petition well before the one-year statutory bar and shortly after receiving infringement contentions. The petition challenges all asserted claims, and because the district court requires the Patent Owner to narrow the number of asserted claims before trial, the IPR would be the only venue to adjudicate the patentability of many of the challenged claims, thus promoting system efficiency.

6. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-5, 9-16, 20-22, and 28 of the ’537 patent as unpatentable.