Samsung Electronics Co Ltd v. Vasu Holdings LLC

1. Case Identification

• Case #: IPR2025-00448
• Patent #: 10,368,281
• Filed: January 24, 2025
• Petitioner(s): Samsung Electronics Co., Ltd., and Samsung Electronics America, Inc.
• Patent Owner(s): Vasu Holdings, LLC
• Challenged Claims: 1, 12, 31, and 37

2. Patent Overview

• Title: Wireless Handover Method and Device
• Brief Description: The ’281 patent discloses a mobile communication device that performs automatic wireless handover between a Wi-Fi network and a cellular network. The alleged invention involves a multi-step process that uses a timer to create time windows for measuring Wi-Fi signal strength and compares it against multiple, different predefined threshold values to decide whether to switch networks.

3. Grounds for Unpatentability

Ground 1: Claims 1, 12, and 37 are obvious over Chaskar in view of Dorenbosch and Willhoff.

• Prior Art Relied Upon: Chaskar (Application # 2004/0137902), Dorenbosch (Application # 2005/0048977), and Willhoff (Patent 6,049,715).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Chaskar taught the core inventive concept: a multi-step handover process from a WLAN to a cellular network based on comparing signal strength against two different, descending thresholds (Th2 and Th3) within distinct "signal strength averaging windows." When signal strength fell below Th2, a first handoff phase was initiated; if it then fell below Th3 in a second window, the handover to cellular was completed. Petitioner contended Dorenbosch supplied the teaching of a dual-transceiver device (WLAN/WAN) and the process of activating a sleeping communication module (e.g., the WAN module) when initiating a handover to reduce power consumption. Willhoff was cited for teaching the use of a timer to establish specific time windows (e.g., "several seconds" or "milliseconds") for averaging signal strength (RSSI), providing the implementation details for Chaskar's "averaging windows."
  • Motivation to Combine: A POSITA would combine Chaskar and Dorenbosch to improve system efficiency and power management, as Dorenbosch explicitly addresses activating a sleeping transceiver to begin a handover process. A POSITA would look to Willhoff to implement Chaskar’s undefined "averaging windows," as Willhoff taught using a timer to create precise time windows of different lengths for signal strength measurement to avoid premature handoffs while ensuring timely switching.
  • Expectation of Success: Petitioner asserted success was expected because all references address the same technical field of wireless network handovers, and combining them involved applying predictable solutions to known problems, such as implementing a measurement window with a timer or activating a sleeping module to save power.

Ground 2: Claims 1, 12, and 37 are obvious over Chaskar, Dorenbosch, and Willhoff in further view of Donovan.

• Prior Art Relied Upon: Chaskar (Application # 2004/0137902), Dorenbosch (Application # 2005/0048977), Willhoff (Patent 6,049,715), and Donovan (Application # 2005/0063348).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground builds on Ground 1, adding Donovan to further support the teaching of a communication module transitioning from a "sleep mode" or "low power mode" to an "active mode." Donovan disclosed a wireless communication device where the RF transceiver is deactivated in sleep mode but can be quickly enabled to transition to active mode, explicitly teaching the power-saving functionality claimed.
  • Motivation to Combine: A POSITA would incorporate Donovan's explicit teachings on sleep/active modes into the primary combination to achieve well-known benefits of power conservation and faster wake-up, which was a common design goal for mobile devices.
  • Expectation of Success: Applying Donovan's conventional power-saving techniques to the handover process of Chaskar/Dorenbosch was argued to be a straightforward and predictable design choice.

Ground 3: Claim 31 is obvious over Chaskar in view of Willhoff and Ruan.

• Prior Art Relied Upon: Chaskar (Application # 2004/0137902), Willhoff (Patent 6,049,715), and Ruan (Application # 2004/0246922).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground challenges claim 31, which adds limitations related to searching for alternative Wi-Fi signals before switching to a wireless (cellular) network. Petitioner argued that the base combination of Chaskar and Willhoff taught the multi-threshold, timer-based handover process. Ruan was added to teach the missing element: when a mobile device's current Wi-Fi signal becomes insufficient, it should first search for and attempt to connect to a different, stronger Wi-Fi access point before resorting to a cellular handover. Ruan disclosed generating a ranked list of candidate access points and attempting to associate with a better one if the current signal quality falls below a threshold.
  • Motivation to Combine: A POSITA would combine Ruan's teachings with Chaskar's system to enhance performance and reduce costs. Instead of immediately initiating a handover to a more expensive cellular network when Wi-Fi signal degrades (as in Chaskar), a POSITA would first search for other available Wi-Fi networks, a more efficient and user-preferred approach.
  • Expectation of Success: Petitioner contended this combination was predictable, as it involved incorporating a known, logical step (searching for a better, same-technology network) into an existing handover procedure to improve its efficiency.

• Additional Grounds: Petitioner asserted an additional obviousness challenge against claim 31 (Ground 4) by adding DeAnna (Application # 2003/0084056) to the combination of Ground 3 to explicitly teach the use of a portable device as a "server," if Chaskar's "mobile node" was deemed insufficient.

4. Arguments Regarding Discretionary Denial

• §325(d) - Same or Substantially Same Art: Petitioner argued against discretionary denial because the primary references relied upon (Dorenbosch, Willhoff, Ruan, Donovan, DeAnna) were never considered during prosecution. Although the Examiner cited Chaskar, it was not considered in the specific combinations asserted in the petition, which are necessary to teach all claim limitations.
• §314(a) - Fintiv Factors: Petitioner argued against denial based on the co-pending district court case, stating that the litigation was in its very early stages, no substantive orders on validity had been issued, and the trial date (11/3/2025) was set for more than three months after the statutory deadline for a Final Written Decision. Petitioner also stated its intent to seek a stay of the litigation if the IPR is instituted.

5. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 1, 12, 31, and 37 of the ’281 patent as unpatentable under 35 U.S.C. §103.