PTAB

IPR2022-00305

Samsung Electronics Co Ltd v. Sonrai Memory Ltd

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Disconnect Condition Creation for Inactive USB Device
  • Brief Description: The ’766 patent discloses a power-saving method for a Universal Serial Bus (USB) system. The method creates an "electrical disconnect" for a USB device that is physically connected but inactive, without unplugging it, by manipulating the data line signals to mimic a physical disconnect state as defined by the USB standard.

3. Grounds for Unpatentability

Ground 1: Obviousness over Cohen and USB 2.0 - Claims 1, 3, 6, 8, 10-11, 13-14, 16, 21, 25-26, 28, 39, 45, 47, 50, 54-55, 57-58 are obvious over Cohen in view of USB 2.0

  • Prior Art Relied Upon: Cohen (Application # 2002/0138776) and USB 2.0 ("Universal Serial Bus Specification," Revision 2.0).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Cohen teaches all limitations of the challenged claims. Cohen discloses a USB system where a USB hub electrically disconnects from a host controller to save power when no downstream devices are attached (i.e., when the hub is inactive). This is achieved by using a Field-Effect Transistor (FET) to electrically remove the pull-up resistor from the D+ data line. According to the USB 2.0 standard, removing the pull-up resistor drives the line low, creating a "Single-Ended 0" (SE0) state, which a host controller is required to interpret as a physical disconnect. Petitioner asserted this directly maps to the claim limitation of an "electrical disconnect" that "causes an appearance to the host controller that the device is not coupled." Cohen also discloses using a "sideband signal" (H8USBON) from attach/removal detection logic to signal the FET to reconnect the pull-up resistor when a device is attached to the hub, satisfying the reconnection limitation.
    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Cohen with the USB 2.0 standard because Cohen explicitly describes a USB system. USB 2.0 was the operative industry standard at the time and would have been essential for a POSITA to understand the implementation details, such as the electrical states for connect/disconnect conditions, that Cohen’s system would need to comply with.
    • Expectation of Success: A POSITA would have a high expectation of success, as the combination involves applying the rules of a well-defined standard (USB 2.0) to a system (Cohen) designed to operate within that standard's framework.

Ground 2: Obviousness over Cohen, USB 2.0, and Tornai - Claims 4-5, 19, 20, 48-49, 60 are obvious over Cohen, USB 2.0, and Tornai

  • Prior Art Relied Upon: Cohen (Application # 2002/0138776), USB 2.0, and Tornai (Patent 5,408,668).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground builds on the teachings of Cohen and USB 2.0 to address dependent claims that require disconnecting the device only "after a wait period." Petitioner argued that Tornai, which relates to power management for computer peripherals, teaches the common-sense use of a timer. Tornai discloses monitoring a peripheral for inactivity and, if no activity is detected for a "selected time limit," sending a deactivation signal to disconnect it from power. This prevents premature disconnection if a user temporarily ceases activity.
    • Motivation to Combine: A POSITA would be motivated to incorporate Tornai’s timer logic into Cohen’s system to enhance its functionality. Both references share the goal of power conservation by deactivating idle peripherals. Adding a wait period as taught by Tornai would make Cohen’s system more robust by ensuring the hub is truly inactive before disconnection, preventing unnecessary re-enumeration cycles and improving the user experience.
    • Expectation of Success: A POSITA would have a high expectation of success in implementing a timer, as it was a well-known, trivial programming task, and the necessary hardware to monitor data line activity was already inherent in Cohen's USB hub design.

Ground 3: Obviousness over Maemura and USB 2.0/1.0 - Claims 1, 6, 8, 10-14, 21, 25-27, 45, 50, 54-58 are obvious over Maemura in view of USB 2.0 and/or USB 1.0

  • Prior Art Relied Upon: Maemura (Patent 6,076,119), USB 2.0, and USB 1.0.
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that Maemura teaches a nearly identical system to that of the ’766 patent. Maemura discloses electrically disconnecting an "inoperative" USB peripheral device from a host computer to save power. It achieves this by using a switching circuit to disconnect a pull-up resistor from its power source, which likewise creates the SE0 disconnect state defined in the USB standards. This causes the host controller to perceive the device as physically disconnected. Maemura further teaches using a signal from the device’s CPU to reconnect the pull-up resistor when the device becomes operative again, fulfilling the sideband signal limitation. Maemura also explicitly discloses using tri-state buffers to disconnect the D+ and D- lines.
    • Motivation to Combine: A POSITA would combine Maemura with the USB 1.0 and/or 2.0 standards because Maemura explicitly states its invention operates "according to the USB...Revision 1.0...standard." A POSITA would naturally consult the relevant standards (USB 1.0 and its successor, USB 2.0) to implement the system Maemura describes.
    • Expectation of Success: Success would be expected, as the combination merely involves applying the express requirements of the USB standard to a system specifically designed for it.

4. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial would be inappropriate under both 35 U.S.C. §325(d) and the Fintiv factors. Under §325(d), Petitioner asserted that the prior art and arguments presented are materially different from those considered during prosecution, as the Examiner never considered Maemura, Tornai, USB 1.0, or USB 2.0, and only considered Cohen in a different combination for a different purpose.
  • Regarding Fintiv, Petitioner argued that the strong merits of the petition weigh in favor of institution. It also noted that the parallel International Trade Commission (ITC) investigation cannot invalidate patent claims, that this petition challenges claims not at issue in the ITC case, and that Petitioner stipulated it would not pursue the same invalidity grounds in the ITC, thus avoiding overlap and inefficiency.

5. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 1, 3-6, 8, 10-14, 16, 19-21, 25-28, 39, 45, 47-50, 54-58, and 60 of the ’766 patent as unpatentable.