PTAB

IPR2017-00978

SanDisk LLC v. Memory Technologies LLC

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Booting a Host Device from a Peripheral Memory Device
  • Brief Description: The ’487 patent discloses a method for booting a host device from a peripheral memory card, such as a Secure Digital (SD) or MultiMediaCard (MMC), using the card's existing interface. The method initiates a boot sequence by setting the command terminal to a low voltage state during power-up, thereby avoiding the need for a dedicated boot pin.

3. Grounds for Unpatentability

Ground 1: Obviousness over Toombs and McClain - Claims 1-3, 5-7, 9, 16, 20, and 21 are obvious over Toombs in view of McClain under 35 U.S.C. §103.

  • Prior Art Relied Upon: Toombs (Patent 6,279,114) and McClain (Patent 7,058,779).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Toombs taught a standard MMC system with a host and peripheral card connected via an interface comprising command, clock, data, and power lines, but did not explicitly teach booting. McClain taught the desirability of booting a computer from non-volatile flash memory and disclosed methods for initiating a boot sequence without adding a dedicated boot pin, specifically by using an "unused state" of an existing signal line.
    • The combination allegedly rendered all challenged independent claims (1, 6, 16, 20) obvious. For the key limitation in independent claim 1 of "setting the command terminal of said MMC/SD interface during power-up to low," Petitioner asserted that Toombs's command line is normally held high during initialization. McClain's teaching to use an unused signal state to indicate boot would have led a person of ordinary skill in the art (POSITA) to apply a low signal to Toombs's command line, as this "low" state was unused and available for this purpose.
    • For the limitation of "monitoring the data bus for a start bit of a data transmission," Petitioner argued that Toombs taught a standard MMC data packet format that begins with a low start bit ('0'). McClain taught that a host device waits for and monitors the memory device to transmit the initial boot code. A POSITA would have configured the host in Toombs's system to monitor for the known start bit to properly receive the boot code taught by McClain.
    • Dependent claims were argued to be obvious by incorporating additional known features of the MMC protocol disclosed in Toombs, such as the standard 74 clock cycles for initialization recited in claims 2 and 7.
    • Motivation to Combine: Petitioner contended that a POSITA would combine Toombs and McClain to add a known and highly desirable booting capability (from McClain) to Toombs's standard MMC card system. McClain taught the advantages of reducing interface lines and initiating boot without a special-purpose pin. This would have motivated a POSITA to implement booting on the standard, low-cost MMC interface disclosed in Toombs by adapting one of its existing signal lines, rather than adding a new one. The combination represented the simple substitution of one known element for another to obtain predictable results.
    • Expectation of Success: A POSITA would have had a reasonable expectation of success in this combination. The approach involved applying a known technique (signaling boot via an unused state on an existing line) to a standard, well-understood interface (the MMC bus) to achieve a predictable function (booting). Given the limited number of communication lines (command, data) and signal states (high, low) in the Toombs system, selecting the command line and its unused low state was presented as one of a finite number of identifiable, predictable solutions.

4. Key Claim Construction Positions

  • Petitioner argued for a specific construction of the phrase in claim 3: "sending a clock signal from said host device to said clock terminal as long as the device has sent the data via said data bus."
    • Proposed Construction: "sending a clock signal from said host device to said clock terminal while the device has sent the data via said data bus."
    • Rationale: Petitioner asserted that the plain language could be interpreted to require the host to wait until the peripheral has sent data before sending a clock signal. However, because the MMC interface is synchronous, such a sequence would be technically impossible; the peripheral device requires a clock signal from the host to be able to send data. Therefore, to give the claim meaning in light of the technology, "as long as" must be construed to mean "while," reflecting the necessary temporal relationship where the clock and data signals are concurrent.

5. Relief Requested

  • Petitioner requests that the Board institute an inter partes review and cancel claims 1-3, 5-7, 9, 16, 20, and 21 of Patent 7,739,487 as unpatentable.