Samsung Electronics Co Ltd v. GenghisComm Holdings LLC

1. Case Identification

• Case #: IPR2025-00791
• Patent #: 11,252,005
• Filed: April 7, 2025
• Petitioner(s): Samsung Electronics Co., Ltd. and Samsung Electronics America, Inc.
• Patent Owner(s): Genghiscomm Holdings LLC
• Challenged Claims: 1, 6-7, 9-11, 13, 18-19, 21-23, 25, 30-31, 33-35

2. Patent Overview

• Title: Wireless Communication Method Using Complex-Valued Code Matrix
• Brief Description: The ’005 patent relates to methods, apparatus, and computer program products for wireless communication, specifically for reducing the peak-to-average power ratio (PAPR) in Orthogonal Frequency Division Multiplexing (OFDM) systems. The invention achieves this by producing subcarrier values from a product of a complex-valued code matrix and data symbols, which shapes interference patterns to create cyclic-shifted waveforms.

3. Grounds for Unpatentability

Ground 1: Anticipation and Obviousness of Claims 1, 6, 9, and 10 over Galda

• Prior Art Relied Upon: Galda (a 2002 IEEE conference paper titled "A Low Complexity Transmitter Structure for OFDM-FDMA Uplink Systems").
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Galda, which describes reducing PAPR in OFDM systems using a Discrete Fourier Transform (DFT) spreading technique, discloses every limitation of independent claim 1. Galda taught producing subcarrier values by multiplying a complex-valued DFT spreading matrix with data symbols. It further described selecting and mapping these values onto a user-specific set of subcarriers, producing a time-domain waveform via an Inverse Fast Fourier Transform (IFFT), and using the DFT codes to shape interference patterns, resulting in cyclic-shifted waveforms. Petitioner contended dependent claims 6 (using an IDFT), 9 (providing for OFDMA), and 10 (defining the complex-valued codes) are also explicitly taught or rendered obvious by Galda.

Ground 2: Obviousness of Claims 13, 18, 21-23, 25, 30, and 33-34 over Galda in view of Dowling

• Prior Art Relied Upon: Galda, Dowling (Patent 6,597,745).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground asserted that the apparatus and computer program product claims (13, 25, and their dependents) are obvious over Galda's method. While Galda taught the underlying method, Dowling taught that functional aspects of OFDM transmitters, such as modulation and precoding, could be implemented as software modules executing on a programmable processor.
  • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Galda's method with Dowling’s implementation teachings. Implementing transmitter functions in software on general-purpose hardware (i.e., a "software radio") was a known technique to increase flexibility and ease of updating compared to a fixed hardware implementation. A POSITA would have been motivated to apply this known software implementation technique to Galda’s known system to achieve the predictable benefits of flexibility.
  • Expectation of Success: A POSITA would have had a reasonable expectation of success, as implementing the mathematical operations described by Galda in software was a routine task for which processors are well-suited.

Ground 3: Obviousness of Claims 7, 19, and 31 over Galda in view of Doufexi

• Prior Art Relied Upon: Galda, Doufexi (a 2002 IEEE symposium paper on 4G OFDM systems).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground addressed claims requiring the selection of one of a "plurality of selectable subcarrier spacings." Petitioner argued that while Galda taught the base system, it did not specify whether its subcarrier spacing was fixed or variable. Doufexi explicitly taught the benefits of using selectable subcarrier spacings (e.g., 16 kHz and 8 kHz) to optimize performance for 4G systems deployed in a wide range of environments.
  • Motivation to Combine: Doufexi provided express motivation, explaining that "a fixed set of parameters is not capable of achieving high performance in all cases" and that a system capable of "dynamically adapting" parameters like subcarrier spacing offers "superior performance." A POSITA would have been motivated to modify Galda’s system with Doufexi’s teaching to improve its adaptability and performance across different operating conditions.
  • Expectation of Success: Selecting among different known subcarrier spacings was a well-understood design choice in OFDM systems with predictable effects on performance, leading to a high expectation of success.
• Additional Grounds: Petitioner asserted additional obviousness challenges based on combinations of Galda (and Dowling) with Lucent (a 3GPP contribution) and Ma (Application # 2015/0256308) for teaching selectable subcarrier spacing, and with Bury (a 2000 IEEE conference paper) for teaching the use of a fast transform (FFT) for DFT spreading.

4. Key Technical Contentions (Beyond Claim Construction)

• Effective Filing Date and Post-AIA Status: Petitioner dedicated significant argument to contending that the ’005 patent is not entitled to its claimed 2004 priority date. Petitioner argued that the patent's effective filing date is no earlier than 2016, and potentially as late as its 2020 filing date, for two primary reasons: (1) the application for the ’005 patent was filed after its parent application had already issued, breaking the chain of co-pendency, and (2) the earlier applications in the priority chain allegedly lack written description support for key limitations, such as "selecting a set of subcarriers assigned for use by a user device" and "selectable subcarrier spacings." Based on this, Petitioner argued the ’005 patent is a post-AIA patent, which alters the scope of available prior art.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under 35 U.S.C. §314(a) based on the Fintiv factors would be inappropriate. The core arguments were that the parallel district court litigation is in a very early stage with minimal investment by the parties or the court. Petitioner stated its intent to seek a stay of the litigation pending the IPR and stipulated that it would not pursue in court any invalidity grounds raised or that reasonably could have been raised in the IPR. Finally, Petitioner asserted that the compelling merits of the petition, which relies on prior art never considered during prosecution, weigh heavily in favor of institution to conserve resources and correct an erroneously issued patent.

6. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1, 6-7, 9-11, 13, 18-19, 21-23, 25, 30-31, and 33-35 of the ’005 patent as unpatentable.