CoolIT Systems Inc v. Asetek Danmark AS

1. Case Identification

• Case #: IPR2020-00524
• Patent #: 9,733,681
• Filed: February 7, 2020
• Petitioner(s): CoolIT Systems, Inc.
• Patent Owner(s): Asetek Danmark A/S
• Challenged Claims: 1, 4, 8, 11, 15, and 16

2. Patent Overview

• Title: Liquid Cooling System for a Computer
• Brief Description: The ’681 patent relates to a liquid-cooling system for a computer. It discloses an integrated element comprising a heat exchange interface, a reservoir for cooling liquid, and a pump, aiming to provide a more compact and efficient system than prior art designs.

3. Grounds for Unpatentability

Ground 1: Obviousness over Duan, Shin, and Cheon - Claims 1 and 4 are obvious over Duan in view of Shin and Cheon.

• Prior Art Relied Upon: Duan (Application # 2006/0185830), Shin (Japanese Application # 2002-151638), and Cheon (Patent 5,731,954).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Duan disclosed the core structure of the claimed system, including a double-sided chassis mounting a pump, a reservoir with separate pump and thermal exchange chambers, and a heat-exchanging interface. To meet the remaining limitations, Petitioner asserted that Shin teaches the missing fan element, describing a DC motor-driven fan for cooling a radiator and enabling control of cooling power via voltage changes. Cheon was then introduced to supply the teaching of a motor control circuit that adjusts pump circulation based on thermal feedback from sensors, thus completing the system claimed.
  • Motivation to Combine: Petitioner asserted a POSITA would combine these references because they all address the common problem of cooling increasingly powerful electronic components within compact spaces. A POSITA would be motivated to improve Duan's integrated cooling module by incorporating the well-known technique of fan-assisted radiator cooling taught by Shin to enhance thermal performance. Furthermore, adding Cheon's temperature-based feedback control would be a simple and predictable step to optimize the system's efficiency and acoustic performance, representing a combination of known elements for their expected purposes.
  • Expectation of Success: Petitioner argued success was expected because the combination involved applying conventional cooling components (a fan, a control system) to a known liquid-cooling architecture to achieve their predictable functions.

Ground 2: Anticipation by Duan - Claims 8, 11, 15, and 16 are anticipated by Duan.

• Prior Art Relied Upon: Duan (Application # 2006/0185830).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner contended that Duan disclosed every element of independent claim 8 and its dependent claims. Specifically, Petitioner argued that Duan’s "accommodation chamber 21" and "lower cover 225" together constitute the claimed "pump chamber," and that Duan's "cap 3" is the direct structural and functional equivalent of the claimed "intermediate member." It further argued Duan's "coil stage 221" is a stator and its "impeller stage 223" is the claimed impeller and rotor, all arranged on opposite sides of the double-sided chassis as required. Petitioner also mapped other limitations, such as the thermal exchange chamber, fluid passages, a recess for the stator (claim 11), and the heat radiator (identified as Duan's "cooling stage 53"), directly to corresponding structures in Duan.
  • Key Aspects: This ground relied heavily on the argument that Duan's "cap 3" meets all the structural and functional requirements of the claimed "intermediate member," a central element of claim 8.

• Additional Grounds: Petitioner asserted an additional obviousness challenge against claims 8, 11, 15, and 16 based solely on Duan, arguing that even if Duan does not explicitly use terms like "stator" or "radiator," these elements would have been obvious to a POSITA from Duan’s disclosure of a "coil stage" and "cooling stage," respectively.

4. Key Claim Construction Positions

• Petitioner argued the term "intermediate member" in claim 8 is a means-plus-function term under 35 U.S.C. §112(6). The claimed functions are partially defining the pump chamber, coupling to the heat-exchanging interface, and defining a second passage. Petitioner identified the corresponding structure in the ’681 patent as element 47. This construction was critical to their anticipation argument in Ground 2, where they mapped Duan's "cap 3" to this structure.
• Petitioner noted that "reservoir" and "chamber" were stipulated in a related district court case to mean "single receptacle defining a fluid flow path" and "compartment within the reservoir," respectively, and adopted those constructions.

5. Arguments Regarding Discretionary Denial

• Petitioner argued the Board should not exercise discretionary denial under §314(a). Key reasons included that the primary prior art reference, Duan, was not considered by the Examiner during the original prosecution of the ’681 patent. Additionally, Petitioner noted that the concurrent district court litigation was in its early stages with no trial date set. Finally, it was argued that the challenged patent belongs to a family with a history of litigation, suggesting that institution would conserve judicial resources and provide guidance for related pending applications.

6. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 1, 4, 8, 11, 15, and 16 of the ’681 patent as unpatentable.