PTAB

IPR2017-00979

SanDisk LLC v. Memory Technologies LLC

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Memory Card Status Signaling
  • Brief Description: The ’469 patent discloses a method and apparatus for communicating between a host and a memory card. The core invention involves using a single signal line to convey two different meanings during a multiple block write command: first to indicate buffer status (e.g., "buffer busy/ready") and later to indicate programming status (e.g., "programming busy/ready"), all within the execution of a single command.

3. Grounds for Unpatentability

Ground 1: Obviousness over MMC 3.31 and CompactFlash - Claims 1-2, 5-8, 10-12, 14-16, and 18-21 are obvious over MMC 3.31 in view of CompactFlash.

  • Prior Art Relied Upon: MMC 3.31 (The MultiMediaCard System Specification, Version 3.31) and CompactFlash (CompactFlash Specification Revision 1.3).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the combination of two well-known memory card standards, MMC 3.31 and CompactFlash, renders the challenged claims obvious under §103. Independent claims 1, 5, 7, 11, 15, and 19 recite communicating information from a first unit (host) to a second unit (memory card) over a signal line, where the memory card drives a change of state on the line that has a first meaning (e.g., buffer status) after a first data block and a second, different meaning (e.g., programming status) after a final data block, all "during" or "within" a single command execution.
    • Petitioner asserted that MMC 3.31 discloses most claimed features, including a host-card architecture, a bus with a data (DAT) line, and multiple-block write commands. MMC 3.31 teaches using a busy signal on the DAT line to indicate buffer status. For "open-ended" multiple block writes, it also discloses a busy signal indicating programming status, but this only occurs after the host sends a separate STOP command, placing the two signals in different command contexts. The challenged claims require both signal meanings to occur within a single, pre-defined block write command execution.
    • To bridge this gap, Petitioner relied on CompactFlash. This standard discloses a pre-defined multiple sector write operation where interrupt signals communicate card status. An interrupt signals that a buffer is ready for the next data sector, while a final interrupt after the last sector signals that programming is complete. Petitioner contended that this teaches the core concept of the ’469 patent: using a signal with two distinct meanings (buffer status and programming status) within a single, pre-defined write command execution to eliminate inefficient host polling.
    • Motivation to Combine: Petitioner argued a person of ordinary skill in the art (POSITA) would be motivated to combine these references to improve performance, a stated goal of both standards. A POSITA seeking to enhance the efficiency of the pre-defined multiple block write operation in MMC 3.31 would look to other contemporary, high-throughput memory standards like CompactFlash. A POSITA would have recognized that applying the efficient, dual-meaning interrupt signaling from CompactFlash’s pre-defined write command to MMC 3.31’s analogous pre-defined write command was a straightforward application of a known technique to a similar system to achieve the predictable result of improved throughput by eliminating polling.
    • Expectation of Success: A POSITA would have had a reasonable expectation of success in this combination. Both MMC 3.31 and CompactFlash are specifications for similar portable flash memory devices that perform block-based data transfers. Modifying the MMC 3.31 protocol to incorporate the signaling logic from CompactFlash would have been a predictable design choice, as the underlying functions and goals were analogous. The petition argued this would not require any undue experimentation.
    • Key Aspects: The argument hinged on the assertion that the only significant difference between the prior art and the ’469 patent was applying the known dual-meaning signaling concept from CompactFlash's pre-defined write to MMC 3.31's pre-defined write, which lacked this specific implementation but was otherwise functionally similar. This modification directly addresses the purported problem of polling inefficiency that the ’469 patent claims to solve.

4. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-2, 5-8, 10-12, 14-16, and 18-21 of Patent 7,565,469 as unpatentable.