US 10749443

Here's a concise summary of US Patent 10749443:

Title: High power multilayer module having low inductance and fast switching for paralleling power devices

Assignee: Wolfspeed Inc. (Current Assignee)
*Original Assignee: Cree Fayetteville Inc.
*Note: The patent was assigned to Cree, Inc. on August 13, 2021, and subsequently to Wolfspeed, Inc. on February 14, 2022, due to a name change from Cree, Inc. to Wolfspeed, Inc. The current assignee is Wolfspeed, Inc.

Inventors: Daniel Martin, Brice Mcpherson, Alexander Lostetter

Filing Date: February 4, 2019

Issue Date: August 18, 2020

Abstract:
A power module is disclosed that includes at least one power substrate, a housing arranged on the at least one power substrate, a first terminal electrically connected to the at least one power substrate, the first terminal comprising a contact surface located above the housing at a first elevation, a second terminal comprising a contact surface located above the housing at a second elevation different from the first elevation, a third terminal electrically connected to the at least one power substrate, and a plurality of power devices electrically connected to the at least one power substrate. The disclosure is also directed to a process of configuring a high power multilayer module having low inductance and fast switching for paralleling power devices.

Plain-Language Overview of Independent Claims:

• Independent Claim 1: This claim describes a power module designed for high power and fast switching. Key features include:

  • At least one power substrate (the base for components).
  • A housing built on the power substrate.
  • A first terminal (e.g., V+) with a contact surface above the housing at a specific height (first elevation).
  • A second terminal (e.g., V-) with a contact surface also above the housing, but at a different height (second elevation) than the first terminal.
  • A third terminal (e.g., phase output) connected to the power substrate.
  • Multiple power devices (like transistors or diodes) connected to the power substrate.
  • The design aims to reduce parasitic inductance and enable fast switching for paralleled power devices.

• Independent Claim 12: This claim focuses on a power conversion system that incorporates the power module from Claim 1, adding external bus bars for connection to capacitors. Key features include:

  • The power module as described in Claim 1.
  • A first planar bus bar electrically connected to the first terminal of the power module.
  • A second planar bus bar electrically connected to the second terminal of the power module.
  • These two planar bus bars are arranged one above the other, which helps minimize inductance in the external connections.

• Independent Claim 13: This claim describes a power module with a focus on current flow to reduce impedance. Key features include:

  • The power module structure similar to Claim 1.
  • Current flows in a first direction from the first terminal, across the power substrate.
  • The current then flows in a second, different direction from the power substrate to the second terminal. This opposing current flow is designed to reduce impedance through flux cancellation.

• Independent Claim 14: This claim outlines a process for manufacturing or configuring such a power module. Key steps include:

  • Providing at least one power substrate.
  • Providing a housing on the power substrate.
  • Electrically connecting a first terminal to the power substrate, where this terminal has a contact surface above the housing at a first elevation.
  • Providing a second terminal with a contact surface above the housing at a different, second elevation.
  • Providing a third terminal electrically connected to the power substrate.
  • Providing a plurality of power devices electrically connected to the power substrate.

USPTO Database Search:
A search on the USPTO website for patent 10749443 confirms its existence and current status as "Active." Public PAIR has been retired and replaced by Patent Center for accessing patent information. The official Patent Public Search tool can be used for quick lookups by patent number.

CAFC 2026 Dockets:
No specific litigation or dockets related to US Patent 10749443 were found in the CAFC 2026 dockets using the provided search terms. The U.S. Court of Appeals for the Federal Circuit website provides general case information but does not offer a direct searchable database for specific patent numbers within dockets for a given year through public search. Therefore, no authoritative information on active litigation was readily available.

As of April 26, 2026, there is known litigation involving US Patent 10749443.

Case Details:

• Plaintiff(s): Wolfspeed, Inc.
• Defendant(s): Navitas Semiconductor
• Jurisdiction: United States District Court for the District of Delaware
  • Note: One search result initially indicated the U.S. District Court for the Western District of North Carolina, but this appears to be an error as multiple other sources confirm the District of Delaware.
• Filing Date: July 7, 2026
• Outcome or Current Status: The lawsuit was recently filed, with Wolfspeed announcing it on July 7, 2026. Wolfspeed alleges that a broad range of Navitas products infringe multiple Wolfspeed patents, including US Patent No. 10,749,443. Products accused of infringement include Navitas's GaN-based FETs (GaNFast®, GaNSlim™, and GaNSafe® product families) and its GeneSiC™ MOSFETs and SiCPAK® modules. The case is ongoing, and Navitas Semiconductor's shares fell following the announcement.

Proceedings overview

There are no AIA trial proceedings on file for US Patent 10749443 according to the USPTO Open Data Portal and supplementary web searches. This means the patent's validity has not been challenged through Inter Partes Review (IPR), Post-Grant Review (PGR), or Covered Business Method (CBM) proceedings at the Patent Trial and Appeal Board (PTAB). For a defendant, this implies that the patent claims have not been subjected to PTAB scrutiny, and an IPR or PGR defense based on prior art patents and printed publications, or other statutory grounds, remains a viable option.

Strategic summary

As of July 9, 2026, all claims of US Patent 10749443 remain untested by the Patent Trial and Appeal Board. There are no records of IPRs, PGRs, or CBMs having been filed against this patent. Consequently, all 14 claims (Independent Claims 1, 12, 13, 14, and dependent claims) are considered valid and patentable in the absence of any PTAB decision to the contrary.

The estoppel landscape is entirely open. Since no PTAB proceedings have occurred, there are no prior art grounds that are barred from being raised by a potential petitioner or defendant. This means any prior art patents or printed publications, or other statutory grounds for invalidity, could still be asserted in a new IPR or PGR petition, assuming the statutory deadlines for filing such petitions are met in relation to any litigation.

The absence of PTAB activity is a notable signal. Patents that are actively asserted and valuable often become targets for IPRs or PGRs. The lack of such challenges for US10749443 could indicate that it has not been extensively asserted in the past, or that potential challengers have not yet identified strong grounds for invalidity that warrant a PTAB petition. Given the recent litigation filed by Wolfspeed against Navitas Semiconductor alleging infringement of US10749443, it is possible that PTAB challenges may emerge in the future.

Recommended next steps

Since no PTAB activity exists for US Patent 10749443, a defendant facing assertion of this patent should consider the following:

• Prior Art Search: Conduct a thorough prior art search to identify any patents or printed publications that could potentially render the claims of US10749443 unpatentable under 35 U.S.C. §§ 102 or 103.
• PGR/IPR Feasibility Assessment: If strong prior art is found, evaluate the feasibility and strategic advantages of filing a Post-Grant Review (PGR) or Inter Partes Review (IPR) petition with the PTAB.
  • PGR: Must be filed within nine months of the patent's issuance (August 18, 2020), and can challenge claims on any ground of invalidity (e.g., §§ 101, 102, 103, 112, except best mode). Given the patent's issue date of August 18, 2020, the nine-month window for filing a PGR has passed.
  • IPR: Can be filed after the later of nine months after the patent's grant date, or if a PGR was instituted, the termination of the PGR. An IPR can challenge claims only on grounds of anticipation (§ 102) or obviousness (§ 103), and only on the basis of prior art consisting of patents or printed publications. An IPR must be filed within 12 months of being served with a complaint alleging infringement.
• Monitor PTAB Filings: Continuously monitor the USPTO's Patent Trial and Appeal Case Tracking System (P-TACTS) for any newly filed petitions against US10749443, particularly in light of the ongoing litigation.
• Coordinate with Litigation Strategy: Any decision to initiate a PTAB proceeding should be carefully coordinated with the overall district court litigation strategy, considering potential stays, claim construction, and estoppel implications.

Inventors

The named inventors for US Patent 10749443 are Daniel Martin, Brice Mcpherson, and Alexander Lostetter. At the time of filing, their employer was Cree Fayetteville Inc., the original assignee of the patent. No unusual patterns, such as all inventors departing within 12 months of filing, are evident from the provided information.

Original assignee

The original assignee listed on US Patent 10749443 is Cree Fayetteville Inc. This entity was engaged in the development and manufacturing of wide bandgap (WBG) power semiconductor devices and modules, particularly those utilizing Silicon Carbide (SiC) and Gallium Nitride (GaN) technologies. The claims of the patent, describing a high power multilayer module, are consistent with the products and technology focus of Cree Fayetteville Inc.

Cree Fayetteville Inc. later merged into Cree, Inc. On February 14, 2022, Cree, Inc. underwent a corporate name change to Wolfspeed, Inc. Therefore, Cree Fayetteville Inc. is no longer an independent operating entity, but its assets and operations have been subsumed by Wolfspeed, Inc., which is an active, operating company in the power semiconductor industry.

Assignment timeline

The following records were found directly on the USPTO Assignment Center (https://assignmentcenter.uspto.gov/) for patent number US10749443.

Contradiction Alert: The USPTO Assignment Center search results for US10749443 do not list the assignments from Cree Fayetteville Inc. to Cree, Inc. (executed August 13, 2021) or from Cree, Inc. to Wolfspeed, Inc. (executed February 14, 2022), nor a security interest from June 30, 2023. These earlier events were detailed in the previously generated "Patent Summary" and are reflected in Google Patents' legal events. In accordance with operating rules, the direct USPTO Assignment Center search results are prioritized as the primary source for this section. The full ownership chain, including these omitted events, is reflected in the Timeline Diagram below.

• 2025-09-30 (executed) / recorded 2025-09-30 — Reel 064185/0749
  • Conveyance: SECURITY INTEREST
  • Assignor: WOLFSPEED, INC.
  • Assignee: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
  • Correspondent: MCGREGOR & ASSOCIATES, P.C., 201 N. TRYON STREET, SUITE 800, CHARLOTTE, NC 28202. This correspondent appears on multiple entries within this securitization chain.
  • Context: Securitization of intellectual property as collateral for a financial agreement.
• 2025-09-30 (executed) / recorded 2025-09-30 — Reel 064185/0751
  • Conveyance: SECURITY INTEREST
  • Assignor: WOLFSPEED, INC.
  • Assignee: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
  • Correspondent: MCGREGOR & ASSOCIATES, P.C., 201 N. TRYON STREET, SUITE 800, CHARLOTTE, NC 28202. This correspondent appears on multiple entries within this securitization chain.
  • Context: Securitization of intellectual property as collateral for a financial agreement.
• 2025-09-30 (executed) / recorded 2025-09-30 — Reel 064185/0753
  • Conveyance: SECURITY INTEREST
  • Assignor: WOLFSPEED, INC.
  • Assignee: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
  • Correspondent: MCGREGOR & ASSOCIATES, P.C., 201 N. TRYON STREET, SUITE 800, CHARLOTTE, NC 28202. This correspondent appears on multiple entries within this securitization chain.
  • Context: Securitization of intellectual property as collateral for a financial agreement.
• 2025-09-30 (executed) / recorded 2025-09-30 — Reel 064185/0755
  • Conveyance: SECURITY INTEREST
  • Assignor: WOLFSPEED, INC.
  • Assignee: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
  • Correspondent: MCGREGOR & ASSOCIATES, P.C., 201 N. TRYON STREET, SUITE 800, CHARLOTTE, NC 28202. This correspondent appears on multiple entries within this securitization chain.
  • Context: Securitization of intellectual property as collateral for a financial agreement.
• 2025-09-30 (executed) / recorded 2025-09-30 — Reel 064185/0747
  • Conveyance: RELEASE OF SECURITY INTEREST IN INTELLECTUAL PROPERTY COLLATERAL AT REEL/FRAME NO. 64185/0755
  • Assignor: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
  • Assignee: WOLFSPEED, INC.
  • Correspondent: MCGREGOR & ASSOCIATES, P.C., 201 N. TRYON STREET, SUITE 800, CHARLOTTE, NC 28202. This correspondent appears on multiple entries within this securitization chain.
  • Context: Release of a previously recorded security interest by the collateral agent.

Timeline diagram

timeline
    title Ownership of US 10749443
    2019 : Filed by Cree Fayetteville Inc
    2020 : Issued
    2021 : Assigned to Cree Inc
    2022 : Assigned to Wolfspeed Inc (name change)
    2023 : Security interest to US Bank
    2025 : Security interest to US Bank
         : Release security interest by US Bank
    2026 : Wolfspeed sues Navitas

NPE / troll-pattern signals

1. Shell-entity transfer — Not present. The assignors (Cree Fayetteville Inc., Cree Inc., Wolfspeed Inc.) are operating companies, and the assignee (U.S. Bank Trust Company, National Association, as Collateral Agent) is a financial institution involved in securitization, not a licensing-only shell entity.
2. Known asserter in the chain — Not present. Wolfspeed, Inc. is an operating company, not identified as a known NPE from the provided list. U.S. Bank Trust Company is a financial institution.
3. Repeat correspondent across the chain — Unclear. MCGREGOR & ASSOCIATES, P.C. is listed as the correspondent for all five security interest and release filings on 2025-09-30 (Reel 064185/0747, 064185/0749, 064185/0751, 064185/0753, 064185/0755). While this shows recurrence within the financial transaction records, the primary USPTO Assignment Center search for this patent does not provide information about the correspondents for the earlier ownership assignments (Cree Fayetteville to Cree, Inc. and Cree, Inc. to Wolfspeed, Inc.). Therefore, it's unclear if this correspondent has handled the entire chain of assignments.
4. Cascading transfers — Not present. While there are multiple security interest filings on the same day in 2025, these represent a single financial event (securitization/refinancing) rather than a series of ownership transfers to multiple chained LLCs. The earlier corporate assignments (2021, 2022) were internal restructurings spread over more than 12 months.
5. Pre-litigation transfer — Not present. The most recent change in the operating owner (Wolfspeed, Inc. via name change) occurred on February 14, 2022. The litigation was filed on July 7, 2026. No ownership transfers occurred within six months prior to the litigation filing. The security interest events in 2025 are not ownership transfers for assertion purposes.
6. Bankruptcy fire-sale — Not present. There is no indication of bankruptcy for any of the operating companies in the chain.
7. Privateering — Not present. Wolfspeed, Inc. is directly asserting the patent against a competitor, without evidence of transferring it to an NPE to assert on their behalf.
8. Defensive aggregator (anti-NPE) — Not present. The patent is held by an operating company that is asserting it, not a defensive aggregator.

Verdict

Operating-company assertion

The patent is currently held by Wolfspeed, Inc., an operating company that develops and manufactures power semiconductor devices. Wolfspeed is actively asserting this patent against Navitas Semiconductor, a direct competitor in the wide bandgap semiconductor market, as confirmed by the litigation filed on July 7, 2026. The assignments recorded on the USPTO Assignment Center are security interests granted to U.S. Bank Trust Company by Wolfspeed, Inc. on 2025-09-30 (Reel 064185/0749, 064185/0751, 064185/0753, 064185/0755), along with a corresponding release on the same date (Reel 064185/0747), which are typical for active businesses and do not indicate an NPE pattern.

USPTO Assignment Center search for US10749443: https://assignmentcenter.uspto.gov/patents/10749443

To identify the most relevant prior art for US Patent 10749443, I will access the patent's full text to review its cited references. The USPTO's Patent Public Search tool and Google Patents are reliable sources for this information. Patent citations are typically provided by both the examiner and the applicant, and they are crucial for assessing the patentability of an invention.

The US Patent 10749443 explicitly lists "Prior art keywords" as "power, power module, configuration, substrate, electrically connected." It also indicates a "Prior art date" of 2017-01-13.

As a language model, I cannot directly perform a live search on the USPTO Patent Public Search tool at this moment for the cited prior art for US Patent 10749443. However, I can state that the official USPTO website provides tools to search for patents and patent application publications, including their cited prior art. The "Common Citation Document - IP5 Offices" also provides up-to-date citation data related to patent applications in participating intellectual property offices.

To accurately fulfill your request, I would need to access the full citation list from the patent document itself. Without direct access to the "References Cited" section of US Patent 10749443, I cannot provide the detailed breakdown of each prior art reference, including its full citation, publication/filing date, brief description, and which claim(s) it potentially anticipates under 35 U.S.C. § 102.

I cannot perform an obviousness analysis of US Patent 10749443 under 35 U.S.C. § 103 as requested.

The "Prior art" section of this analysis explicitly states that I do not have access to the full citation list or detailed descriptions of the prior art references cited within US Patent 10749443. Without this specific information, it is impossible to:

1. Identify specific combinations of prior art references.
2. Determine which claims (independent or dependent) might be rendered obvious by these combinations.
3. Articulate the motivation for a person having ordinary skill in the art (PHOSITA) to combine such references.

To conduct a proper obviousness analysis, I would need access to the content of the cited prior art documents to compare their teachings against the claims of US Patent 10749443.