Cooler Master Co Ltd v. Aavid Thermalloy LLC

1. Case Identification

• Case #: IPR2019-00333
• Patent #: 7,100,679
• Filed: November 14, 2018
• Petitioner(s): Cooler Master Co., Ltd.
• Patent Owner(s): Aavid Thermalloy LLC.
• Challenged Claims: 1, 2, 4, 5

2. Patent Overview

• Title: Integrated Circuit Heat Pipe Heat Spreader with Through Mounting Holes
• Brief Description: The ’679 patent describes heat pipes, or vapor chambers, for cooling electronic components. The invention is directed to structures and methods for creating through-holes for mounting fasteners within the main body of the heat pipe while maintaining the hermetic seal of the internal vapor chamber.

3. Grounds for Unpatentability

Ground 1: Obviousness over Morikawa and Nakamura - Claims 1, 2, 4, and 5 are obvious over Morikawa in view of Nakamura.

• Prior Art Relied Upon: Morikawa (Japanese Examined Utility Model Application Publication S53-32387 Y) and Nakamura (Japanese Unexamined Utility Model Application Publication S50-55262).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Morikawa disclosed the fundamental structure of a panel-type heat pipe comprising a boundary structure with spaced-apart plates defining a sealed vapor chamber, as required by independent claim 1. Morikawa’s "metal pipes 11a" were identified as teaching the claimed "spacer" positioned within the vapor chamber and extending between the plates. Petitioner asserted that Nakamura supplied the remaining limitations of claim 1 by teaching the use of a "concavity" (the claimed "depression") formed in one plate that projects into the chamber and is bonded to the opposing plate. This concavity in Nakamura includes a through-hole for component mounting, teaching the claimed "opening defined through said depression." For the dependent claims, Petitioner argued Nakamura taught a wick (claim 2), an annular bonding surface on its concavity (claim 4), and Morikawa taught bonding the plates at their peripheral edges (claim 5).
  • Motivation to Combine (for §103 grounds): A POSITA would combine the references as both address the same technical problem of creating mounting holes in heat pipes. Petitioner provided a compelling motivation by showing that Nakamura expressly names Morikawa by its Japanese filing number, critiques its design as having manufacturing disadvantages (e.g., difficulty in joining the metal spacer pipes), and explicitly proposes its concavity-based structure as a simpler and more effective solution to those known problems.
  • Expectation of Success (for §103 grounds): A POSITA would have a high expectation of success, as Nakamura's teachings represented a direct and advantageous modification aimed at improving the known Morikawa design.

Ground 2: Obviousness over Morikawa, Nakamura, and Takahashi - Claim 5 is obvious over Morikawa in view of Nakamura and further in view of Takahashi.

• Prior Art Relied Upon: Morikawa, Nakamura, and Takahashi (Japanese Examined Utility Model Application Publication H8-10205).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground focused on strengthening the obviousness rationale for claim 5’s "peripheral lip...bonded together" limitation. Petitioner contended that Takahashi taught an improved structure for sealing the periphery of a heat pipe. Specifically, Takahashi disclosed forming outwardly protruding "flanges (17)" on the edges of the heat pipe's constituent plates. These flanges, which correspond to the claimed "peripheral lip," are then joined in a parallel orientation to form a robust seal.
  • Motivation to Combine (for §103 grounds): Petitioner argued that the method of bonding the plate edges shown in Morikawa (a perpendicular butt joint) was known to be difficult from a manufacturing standpoint, making it hard to align, clamp, and seal effectively. A POSITA seeking to improve the manufacturability of the Morikawa/Nakamura device would look to analogous art like Takahashi, which taught a "better way" to seal plates using flanges. This flange configuration facilitates easier manufacturing processes like pressing, soldering, or brazing, as the joint is more accessible.
  • Expectation of Success (for §103 grounds): A POSITA would reasonably expect success in applying Takahashi's well-known flange design to the Morikawa/Nakamura heat pipe, as it was a straightforward and predictable manufacturing improvement.

4. Key Claim Construction Positions

• "Spacer": Petitioner proposed the construction "structure used to maintain a space or clearance between the plates." Petitioner argued the Patent Owner's construction, which required the spacer to be a structure "apart from the separately claimed depression," was improper. This was because the ’679 patent’s specification explicitly states that "spacers can be...embossed depressions," directly contradicting the Patent Owner's attempt to exclude them.
• "Vapor Chamber": Petitioner proposed "an enclosed and hermetically sealed void or cavity in which a working fluid is present..." This construction challenged the Patent Owner’s inclusion of functional limitations that "capillary forces are utilized." Petitioner argued this was unduly limiting because the claims do not require a wick, and wickless heat pipes that do not rely on capillary forces were well-known in the art at the time of the invention.
• "Lip": Petitioner proposed the construction "portion of the plate comprising a region bonded to another plate." This was contrasted with the Patent Owner’s construction defining the lip as a "[p]ortion of the plate defined by the bonded region of the plate's inner or interior surface." Petitioner argued the Patent Owner's construction was nonsensical because a region bonded to another plate is, by definition, no longer an "inner or interior surface" of the heat pipe.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under 35 U.S.C. § 325(d) would be inappropriate. The petition was asserted to be substantially different from a previously filed petition because it relied on a new primary reference (Morikawa) that was not cited during prosecution. This shift in primary art was argued to create fundamentally different unpatentability arguments, especially regarding the "spacer" limitation, which is explicitly recited in Morikawa but not in the prior art used in the previous petition.

6. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 1, 2, 4, and 5 of the ’679 patent as unpatentable.