PTAB

IPR2025-01111

Samsung Electronics Co Ltd v. Wilus Institute Of Standards Technology Inc

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Wireless Communication Terminal And Wireless Communication Method For Multi-User Concurrent Transmission
  • Brief Description: The ’186 patent discloses a method and terminal for managing simultaneous multi-user uplink transmissions in a wireless network. The technology centers on using a "trigger frame" that includes an association identifier (AID) field and a padding field, where a specific value in the AID field indicates the presence and start of the padding, which provides terminals additional time to process the trigger frame.

3. Grounds for Unpatentability

Ground 1: Claims 1-18 are obvious over Kim.

  • Prior Art Relied Upon: Kim (Application # 2019/0357256).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Kim, a single reference, discloses all limitations of the challenged claims. Kim describes a multi-user uplink system where an access point sends a trigger frame to multiple stations. This trigger frame explicitly includes a User Information field containing an "AID 12 subfield," a "Padding field," and a "Frame Check Sequence (FCS) field." Crucially, Kim teaches that setting the AID 12 subfield to a specific reserved value (4095) "signifies the start of a Padding field." This directly maps to the core limitations of independent claims 1 and 11, which require using the AID field to identify the presence of a padding field when the AID is set to a specific value. Kim further teaches that the padding field's purpose is to extend the trigger frame's length, allowing a recipient station time "to prepare for an SIFS response," which Petitioner equated to the claimed "time needed for the one or more terminals to process the trigger frame."
    • Key Aspects: Petitioner contended that Kim's disclosure of using the specific AID value of 4095 (which corresponds to twelve binary 1s) to signal the start of padding renders obvious the dependent claims related to "duplicated bit information" (claim 5) and applying padding by duplicating information (claims 6 and 7).

Ground 2: Claims 1-18 are obvious over Chu in view of Choi.

  • Prior Art Relied Upon: Chu (Application # 2015/0131517) and Choi (Application # 2015/0230244).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that Chu teaches a multi-user uplink system using a scheduling frame (equivalent to the claimed trigger frame) containing an AID and padding. Chu discloses that the purpose of the padding is to provide "sufficient time for the client stations to prepare for uplink transmission," which aligns with the ’186 patent. However, Petitioner argued that Chu fails to teach a specific mechanism for signaling the start of this padding. Choi was argued to supply this missing element by teaching a method to signal the beginning of padding bits in a frame by setting an AID-related field (a differential AID or ΔAID field) to a specific reserved value (e.g., "11").
    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Chu and Choi to solve a known problem. Chu’s system is incomplete because it lacks a clear method for a receiving station to distinguish padding bits from meaningful scheduling data. A POSITA would look to known techniques for a solution and find one in Choi, which explicitly addresses frame parsing and padding identification in a similar wireless context. The motivation would be to apply Choi's specific, efficient signaling mechanism to Chu’s conceptual framework to create a more robust and reliable system.
    • Expectation of Success: A POSITA would have a reasonable expectation of success because the combination involves applying a known, modular solution (Choi's padding marker) to a known problem (Chu's lack of a padding marker) in the same technical field. The integration would be straightforward and predictable, improving frame parsing efficiency without requiring fundamental changes to Chu’s architecture.

4. Key Technical Contentions (Beyond Claim Construction)

  • Contention over Patent’s Critical Date: Petitioner argued that the ’186 patent is not entitled to its claimed priority dates and that its critical date is its filing date of April 8, 2019. The argument was based on an alleged lack of written description support in the priority applications for the key limitations added during prosecution—namely, that "the AID field is used to identify whether the trigger frame includes a padding field" and that the padding field is included "when the AID field is set to a specific value." By establishing a later critical date, Petitioner positioned Kim, which has an effective filing date of January 8, 2018, as valid prior art for its Ground 1 obviousness challenge.

5. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial is unwarranted. The petition noted an intent to use the bifurcated briefing process established by the March 26, 2025, Stewart Memorandum to rebut any arguments for discretionary denial, such as those based on the Fintiv factors, that the Patent Owner might raise. This signals an assertion that the merits of the petition are strong and that parallel district court litigation should not preclude institution.

6. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-18 of the ’186 patent as unpatentable.