Google LLC v. Advanced Coding Technologies LLC

1. Case Identification

• Case #: IPR2025-01161
• Patent #: 7,804,891
• Filed: June 17, 2025
• Petitioner(s): Google LLC
• Patent Owner(s): Advanced Coding Technologies LLC
• Challenged Claims: 1-9

2. Patent Overview

• Title: Device and Method for Judging Communication Quality and Program Used for the Judgment
• Brief Description: The 7,804,891 patent relates to a device and method for judging communication quality in a wireless communication system. The technology aims to accurately detect or correct bit errors in transmitted voice data to improve the quality of reproduced voice.

3. Grounds for Unpatentability

Ground 1: Claims 1-9 are obvious over IS-54-B, Dent, Yeh, and Mårtensson.

• Prior Art Relied Upon: IS-54-B (EIA/TIA Interim Standard, April 1992), Dent (Patent 5,555,257), Yeh (a 1998 technical paper titled "Advanced Vocoder Idle Slot Exploitation for TIA IS-136 Standard"), and Mårtensson (Patent 6,519,740).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that the primary reference, IS-54-B, a well-known cellular standard, taught the core elements of a communication quality judging system. IS-54-B disclosed obtaining a baseband signal, checking for errors using a cyclic redundancy check (CRC), and employing a "bad frame masking" process to change data by repeating, attenuating, or muting speech based on the error check. Petitioner asserted that the remaining references supply the specific limitations not explicitly found in IS-54-B. Dent was cited for teaching standard techniques for demodulating a signal and judging symbols at the Nyquist rate. Yeh was cited for teaching the use of a threshold, such as a Hamming distance metric, to determine if a "predetermined condition" of poor quality is met before changing data. Finally, Mårtensson was alleged to teach judging communication quality by analyzing the reliability of individual bits using "soft values" and protecting portions of a bit string with redundant bits having a predetermined value.
  • Motivation to Combine: Petitioner contended a person of ordinary skill in the art (POSITA) would combine these references to improve the known system of IS-54-B. A POSITA would incorporate Dent's teachings to use a well-known, accurate technique for symbol judging. A POSITA would add Yeh's threshold-based condition to provide more flexibility and better error detection than IS-54-B's basic CRC check, especially since Yeh was designed to be backward-compatible with the IS-54-B standard family. Mårtensson would be combined to use available "soft information" from a Viterbi decoder—a known technique—to more reliably assess communication quality and protect specific bits through repetition.
  • Expectation of Success: Petitioner asserted a POSITA would have had a reasonable expectation of success because the combination involved applying known, predictable solutions to improve a standard communication system. The compatibility of the references (e.g., Yeh's backward compatibility) and the use of standard signal processing techniques would ensure a predictable outcome.

Ground 2: Claims 1-9 are obvious over IS-54-B, Dent, and Su.

• Prior Art Relied Upon: IS-54-B (EIA/TIA Interim Standard, April 1992), Dent (Patent 5,555,257), and Su (Patent 5,255,343).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground presented an alternative combination where Su replaced Yeh and Mårtensson. IS-54-B and Dent provided the same foundational teachings as in Ground 1 for a base system and symbol judging. Su, which was explicitly designed as an improvement for the IS-54-B standard, taught an enhanced "bad frame masking" technique. Su disclosed using a maximum likelihood (ML) check in addition to a CRC check, with the ML threshold corresponding to the claimed "predetermined condition" for changing data. Su also taught dividing bits into protected portions (Group A and Group B) and using a Hamming distance metric in the decoding process, which Petitioner mapped to the limitations requiring protected bit strings and identifying redundant bits to judge quality.
  • Motivation to Combine: The motivation was argued to be explicit and compelling. Su stated its purpose was to provide an "improved error detection and bad frame masking technique" compatible with the IS-54-B standard. A POSITA seeking to enhance the performance of an IS-54-B system would have been directly motivated to implement the improvements taught by Su.
  • Expectation of Success: Petitioner argued the expectation of success would have been high because Su was specifically designed to be integrated with IS-54-B. The combination represented the integration of a purpose-built improvement into its target system, a predictable engineering task.

4. Key Claim Construction Positions

• Petitioner dedicated a section to construing several means-plus-function limitations to demonstrate that the prior art taught structures capable of performing the claimed functions.
• "symbol judging means" (claims 1-7): Petitioner proposed this term covers the functions of obtaining a baseband signal and judging the symbol it represents. The corresponding structure was identified as a demodulator and a processor that determines a symbol value by comparing the signal against threshold values.
• "communication quality judging means" (claims 1-7): This was construed to cover judging quality based on the number of redundant bits having or missing a predetermined value. The corresponding structure was identified as a processor that checks bit values and compares the count to thresholds.
• "data changing means" (claims 1-7): This was construed to cover making a predetermined change to data (e.g., replacing, muting, attenuating). The corresponding structure was identified as a processor executing these functions.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that the Board should not exercise discretionary denial under either 35 U.S.C. §325(d) or §314(a).
• Regarding §325(d), Petitioner asserted that its primary prior art references (IS-54-B, Dent, Yeh, and Su) were not applied or considered during the original examination, and thus the petition raised new arguments not cumulative to those before the examiner.
• Regarding discretionary denial under Fintiv, Petitioner argued the parallel district court litigation was in its early stages, with a trial not scheduled until March 2026. Petitioner also noted that the IPR challenges all claims (1-9), whereas the litigation involves a subset (1-4, 6, 8-9), meaning the IPR would address patentability of claims 5 and 7, which are not part of the district court case, thereby reducing overlap and promoting efficiency.

6. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1-9 of the ’891 patent as unpatentable.