Cooler Master Co Ltd v. Aavid Thermalloy LLC

1. Case Identification

• Case #: IPR2019-00146
• Patent #: 7,100,679
• Filed: October 31, 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 discloses a heat pipe, also described as a vapor chamber, designed for cooling electronic components. The invention focuses on methods for creating through-holes for mounting the heat pipe directly to a component while maintaining the hermetic seal of the internal vapor chamber.

3. Grounds for Unpatentability

Ground 1: Claims 1, 2, 4, and 5 are obvious over Nakamura

• Prior Art Relied Upon: Nakamura (Japanese Unexamined Utility Model Application S50-55262).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Nakamura, a 1975 publication, taught all elements of the challenged claims. Independent claim 1’s requirement for a "boundary structure including spaced-apart first and second plates" was allegedly disclosed by Nakamura’s "sealed container" made of metal plates. The claimed "spacer" was met by Nakamura’s H-shaped structures (concavities 9 and joining surfaces 9a) that prevent the container walls from deforming. The claimed "depression...bonded to said second plate" was mapped to Nakamura’s "concavity" (9) that projects into the container and is adhered to the opposing plate. Finally, the "opening defined through said depression...isolated from said vapor chamber" was allegedly shown by Nakamura’s mounting hole (11), which passes through the bonded concavity, sealing it from the internal chamber. Petitioner asserted that Nakamura also taught the dependent claim limitations, including a "wick" (element 8 in Nakamura) for claim 2, annular bonding surfaces for claim 4, and an inherent peripheral lip for claim 5.
  • Motivation to Combine (for §103 grounds): Not applicable as this ground relies on a single reference.
  • Expectation of Success (for §103 grounds): Not applicable.

Ground 2: Claims 1, 2, 4, and 5 are obvious over Nakamura in view of Takahashi

• Prior Art Relied Upon: Nakamura (Japanese Unexamined Utility Model Application S50-55262) and Takahashi (Japanese Examined Utility Model Application, published 1991).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground was presented as an alternative, primarily to address the "peripheral lip" limitation of claim 5 if the Board found Nakamura alone insufficient. Petitioner argued that Nakamura taught all elements of claims 1, 2, and 4. Takahashi was introduced to explicitly teach the peripheral sealing structure, disclosing "flanges (17)" at the tips of the peripheral walls of its plate members, which are joined to form a sealed container. These flanges, Petitioner contended, directly correspond to the "peripheral lip" recited in claim 5.
  • Motivation to Combine (for §103 grounds): A person of ordinary skill in the art (POSITA) would combine Nakamura and Takahashi because both disclose heat pipes with through-holes for mounting and describe similar manufacturing techniques ("pressing" in Nakamura and "press-molding" in Takahashi). A POSITA seeking to implement the peripheral seal in Nakamura’s design would have been motivated to incorporate the explicit peripheral flanges taught by Takahashi as a well-known and effective sealing method in the same technical field.
  • Expectation of Success (for §103 grounds): A POSITA would have had a high expectation of success in combining the known flange-based sealing technique from Takahashi with the heat pipe structure of Nakamura, as it involved the application of a conventional sealing method to a similar device.

4. Key Claim Construction Positions

• "Vapor Chamber": Petitioner proposed the construction "enclosed and sealed space or cavity in which a heat transfer fluid is present to be evaporated (or vaporized) and condensed to transport or spread heat." This construction was argued to be superior to the Patent Owner’s proposed "vacuum sealed chamber...[where] capillary forces are utilized." Petitioner contended that "vacuum sealed" is ambiguous and inaccurate, as the specification uses "vacuum" to mean "isolated" or "sealed," and the chamber itself contains fluid and can operate above atmospheric pressure. Furthermore, requiring capillary forces improperly imported a limitation from optional features, as the independent claim does not require a wick, and wicks (which generate capillary forces) are only added in dependent claims.
• "Lip": For claim 5, Petitioner proposed "portion of the plate comprising a region bonded to another plate." This was argued to be a broader and more accurate construction than the Patent Owner's, which required the lip to be a portion of the plate's "inner or interior surface." Petitioner asserted the Patent Owner's construction was self-contradictory because once a region is bonded to another plate to form a seal, it is no longer an "inner" or "interior" surface of the heat pipe.
• "Spacer": Petitioner proposed the construction "structure used to maintain a space or clearance between the plates." Petitioner argued the Patent Owner’s proposal, which required the spacer to be "apart from the separately claimed depression" and to "provide support for a capillary wick," was improper. The ’679 patent specification explicitly states that spacers can be "embossed depressions," directly contradicting the Patent Owner’s proposed exclusion. Additionally, requiring support for a wick improperly imported an optional feature from dependent claims into the construction of a term in the independent claim.

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 the challenges were based on new prior art—specifically Nakamura and Takahashi—that was never cited or considered by the examiner during the original prosecution of the ’679 patent. Therefore, the petition presented new arguments and grounds of unpatentability that had not been previously evaluated by the USPTO.

6. Relief Requested

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