ARM Limited v. COMPLEX MEMORY, LLC

1. Case Identification

• Case #: IPR2019-00058
• Patent #: 6,658,576
• Filed: October 12, 2018
• Petitioner(s): ARM LTD. and ARM, INC.
• Patent Owner(s): COMPLEX MEMORY, LLC
• Challenged Claims: 25

2. Patent Overview

• Title: Energy-Conserving Operating System
• Brief Description: The ’576 patent discloses an apparatus and method for an energy-conserving operating system. The system uses a low-power "keep-alive" microprocessor and instruction set to monitor for events, and a high-power "main" microprocessor and instruction set that is activated only when needed for more computationally intensive tasks.

3. Grounds for Unpatentability

Ground 1: Anticipation over Smith

• Prior Art Relied Upon: Smith (Patent 5,167,024).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Smith discloses every element of claim 25 under the claim construction required by the prosecution history. Smith teaches a portable computer with a low-power Power Manager (PMGR) microcontroller (a Mitsubishi chip) and a high-power main CPU (a Motorola 68000). Petitioner mapped Smith’s PMGR to the "keep-alive microprocessor circuitry" and its embedded software to the "keep-alive operating instructions." This keep-alive system monitors for events like a ring signal. Smith’s main CPU was mapped to the "main microprocessor circuitry" with its own "main operating instructions." Smith describes powering up the main CPU upon detecting a "power-up signal" (e.g., a key press, ring signal, or wake-up timer) and powering down by deactivating the main CPU upon detecting a "power-down signal" (e.g., a low battery condition or an inactivity command). The PMGR's operation inherently requires less computation power.
  • Key Aspects: Petitioner contended that Smith’s two processors execute different instruction sets from their own distinct memory and ROM, meaning they do not use a "common operating instruction set." This directly aligns with the patentee's disclaimer during prosecution to distinguish the invention from the Barber prior art, making Smith's disclosure particularly relevant.

Ground 2: Anticipation over Perry

• Prior Art Relied Upon: Perry (Patent 5,142,684).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Perry describes a dual-microprocessor architecture that anticipates claim 25, consistent with the required claim construction. Perry’s low-power 8-bit Motorola "Microcomputer Unit," which operates continuously for background tasks, was mapped to the claimed "keep-alive" system. Perry’s high-power 16-bit RTX 2000 Microcontroller, used for computationally intensive foreground tasks, was mapped to the "main" system. Perry teaches that the keep-alive processor activates the main processor when a foreground task is required (a "power-up signal"), which is a more computationally intensive operation. The low-power processor deactivates the main processor after a predetermined period of inactivity (a "power-down signal") to conserve power.
  • Key Aspects: Similar to the argument regarding Smith, Petitioner emphasized that Perry's two microprocessors are fundamentally different, run separate and distinct instruction sets, and do not share a common operating system. The low-power processor requires 2V while the high-power processor requires 5V, clearly teaching an energy-conserving operation that requires less computation power than the main operation.

Ground 3: Anticipation over Matoba (Contingent Ground)

• Prior Art Relied Upon: Matoba (Patent 5,913,068).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground was argued in the alternative, contingent on the Board adopting a broader claim construction that does not require separate operating systems. Petitioner asserted that if the patentee's prosecution disclaimer is ignored, Matoba anticipates claim 25. Matoba describes a system with multiple CPUs having different power consumptions and performance levels. Its CPU switching control software selects a CPU based on system load, switching to a low-power CPU to conserve energy. This act of switching to the low-power CPU was mapped to the "powering down" step, which deactivates the main (high-power) CPU. Switching back to the high-power CPU when performance is needed was mapped to the "powering up" step.
  • Key Aspects: The central point of this ground is that Matoba’s different CPUs can run under a single, common operating system and execute the same programs from the same memory space. While this contradicts the narrow construction Petitioner advocated for in its primary grounds, Petitioner argued it meets the literal claim language. This argument was presented to counter any attempt by the Patent Owner to argue for a broader claim interpretation than what was presented during prosecution.

• Additional Grounds: Petitioner asserted additional challenges that claim 25 is anticipated by Harper (Patent 5,560,024) under a broader claim construction. Petitioner also presented obviousness grounds under 35 U.S.C. §103, arguing that to the extent any of the four references (Smith, Perry, Matoba, or Harper) were found not to anticipate, each would have rendered claim 25 obvious to a person of ordinary skill in the art.

4. Key Claim Construction Positions

• Petitioner argued that the terms "set of keep-alive operating instructions" and "set of main operating instructions" must be narrowly construed based on a clear and unambiguous disclaimer made during prosecution to overcome a rejection over the Barber patent.
• To distinguish Barber, the applicant stated that Barber’s processors "utilize a common operating instruction set," whereas the claimed invention uses "two sets of operating instructions" and "two sets of operating systems" (e.g., a DOS version for the keep-alive function and Windows XP for the main function).
• Based on this disclaimer, Petitioner contended that the only proper construction requires that the two sets of instructions (1) cannot utilize a "common operating instruction set" and (2) must constitute two separate and distinct operating systems. This construction was foundational to Petitioner’s primary arguments based on Smith and Perry.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under 35 U.S.C. §325(d) would be inappropriate.
• The core reason provided was that none of the asserted prior art references (Smith, Perry, Matoba, Harper) or the specific anticipation and obviousness arguments based upon them were the same or substantially the same as those previously presented to or considered by the examiner during the original prosecution of the ’576 patent.

6. Relief Requested

• Petitioner requested that the Board institute an inter partes review, find claim 25 of the ’576 patent unpatentable on all eight asserted grounds, and cancel the claim.