CoolIT Systems Inc v. Asetek Danmark AS

1. Case Identification

• Case #: IPR2020-00523
• Patent #: 10,078,354
• Filed: February 7, 2020
• Petitioner(s): CoolIT Systems, Inc.
• Patent Owner(s): Asetek Danmark A/S
• Challenged Claims: 1, 4, 8, 14, 15, and 19

2. Patent Overview

• Title: Liquid-cooling system for a computer system
• Brief Description: The ’354 patent describes a compact liquid-cooling system for computer processing units (CPUs). The invention purports to provide a more efficient and low-cost solution than traditional air-cooling by integrating a heat exchanging interface, a reservoir, and a pump into a single element mounted on the CPU.

3. Grounds for Unpatentability

Ground 1: Obviousness over Batchelder in view of Shin - Claims 1, 8, and 15 are obvious over Batchelder in view of Shin.

• Prior Art Relied Upon: Batchelder (Patent 6,019,165) and Shin (Japanese Application Pub. No. 2002-151638).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Batchelder disclosed the core limitations of the challenged claims, including a cooling system with a reservoir comprising vertically displaced upper and lower chambers, a heat exchanging interface, and a pump with an impeller positioned in the upper chamber. Batchelder’s system, however, lacked an external radiator. Petitioner asserted that Shin supplied this missing element, teaching a cooling structure with a pump and heat sink connected to a separate, external heat exchange section (radiator) to dissipate heat away from the primary assembly. Furthermore, Petitioner contended that while Batchelder’s coolant flows from the periphery to the center, Shin taught the claimed configuration of directing coolant from a central region toward the perimeter of the lower chamber.
  • Motivation to Combine: Petitioner argued a person of ordinary skill in the art (POSITA) would combine Batchelder and Shin because both references addressed the same problem of cooling high-density electronic components with reliable, compact, and low-cost liquid systems. A POSITA would have been motivated to improve the thermal performance of Batchelder’s integrated system by incorporating Shin’s teaching of an external radiator, a well-known technique for enhancing heat dissipation. Modifying the fluid flow direction in Batchelder to match Shin's center-to-periphery flow was presented as an obvious design choice to optimize heat absorption across the component surface.
  • Expectation of Success: Petitioner asserted a POSITA would have had a reasonable expectation of success in combining these known elements. Adding a standard component like an external radiator to Batchelder’s liquid loop was a predictable modification that would predictably improve cooling efficiency.

Ground 2: Obviousness over Batchelder in view of Shin and Cheon - Claims 4, 14, and 19 are obvious over Batchelder in view of Shin and Cheon.

• Prior Art Relied Upon: Batchelder (Patent 6,019,165), Shin (Japanese Application Pub. No. 2002-151638), and Cheon (Patent 5,731,954).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground built upon the combination of Batchelder and Shin from Ground 1 to address dependent claims requiring a control system. Petitioner argued that Shin disclosed a basic control system by teaching that using a DC motor allows pump speed to be easily changed by varying the DC voltage, thereby enabling control of cooling power. To meet the more specific limitations, Petitioner introduced Cheon. Cheon taught a motor control circuit that adjusts coolant circulation based on feedback from a temperature sensor (thermistor), which directly addressed the claim 4 limitation of adjusting the pump based on a measured operating temperature. For claim 14, Petitioner combined Shin's disclosure of an air-cooling fan with Cheon's teaching of a noise-free system to argue for a control system that adjusts both fan and pump speed to reduce noise. For claim 19, Petitioner argued Cheon's temperature-based feedback system directly taught a control system that determines a required cooling capacity and adjusts pump speed accordingly.
  • Motivation to Combine: Petitioner contended that a POSITA, having combined Batchelder and Shin to create an efficient cooling apparatus, would be motivated to incorporate Cheon’s teachings to add intelligent control. The goals of power conservation, noise reduction, and increased component longevity, all addressed by Cheon’s control system, were well-aligned with the objectives of high reliability and efficiency in Batchelder and Shin. All three references aimed to provide low-cost, reliable cooling solutions for computer systems, making their combination logical and predictable.
  • Expectation of Success: Petitioner argued that integrating a known temperature-based feedback control circuit (from Cheon) into the liquid cooling system of Batchelder/Shin was a straightforward application of conventional electronics to improve system performance, with a high expectation of success.

4. Key Claim Construction Positions

• "reservoir": Petitioner noted that the parties stipulated in co-pending district court litigation to construe "reservoir" as a "single receptacle defining a fluid flow path." The petition argued that the claims require this single receptacle to encompass components like the pump chamber and thermal exchange chamber.
• "chamber": Similarly, Petitioner relied on the stipulated construction of "chamber" as a "compartment within the reservoir."

5. Arguments Regarding Discretionary Denial

• Petitioner argued that the Board should not exercise its discretion to deny institution under 35 U.S.C. §314(a). It was asserted that although the primary reference, Batchelder, was listed in an Information Disclosure Statement during prosecution, the Examiner never substantively applied it against the claims. Petitioner also cited an extensive litigation history involving the patent family as a reason to institute and provide guidance. Finally, Petitioner stated that the concurrent district court litigation was not in an advanced stage, with no trial date or expert discovery deadlines set, thus weighing against a discretionary denial under Fintiv.

6. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1, 4, 8, 14, 15, and 19 of the ’354 patent as unpatentable.