Assignment history

Inventors

Patrick L. Chapman, Brian T. Kuhn, Robert S. Balog, Jonathan W. Kimball, Philip T. Krein, and Alexander Gray. All inventors were associated with Solarbridge Technologies Inc. at the time of filing.

Original assignee

Solarbridge Technologies Inc. was the original assignee. Solarbridge Technologies Inc. developed microinverters for solar panels. The company was acquired by SunPower Corporation in 2014, and then later by Enphase Energy Inc. in 2018. It is currently part of Enphase Energy Inc..

Assignment timeline

• 2010-03-26 (executed) / recorded 2010-03-26 — Reel 024195/0268

  • Conveyance: Assignment
  • Assignor: Philip T. Krein, Jonathan W. Kimball, Robert S. Balog, Patrick L. Chapman, Alexander Gray, Brian T. Kuhn
  • Assignee: Solarbridge Technologies, Inc.
  • Correspondent: Jeffrey C. Hanley, Hanley Flight & Zimmerman LLC, 150 S Wacker Drive Suite 2420, Chicago IL 60606. This correspondent does not recur in this chain.
  • Context: Original assignment from inventors to company.

• 2014-09-02 (executed) / recorded 2014-09-03 — Reel 032230/0398

  • Conveyance: Security Interest
  • Assignor: Solarbridge Technologies, Inc.
  • Assignee: Silicon Valley Bank
  • Correspondent: David H. Dolkas, Esq., Sunpower Corporation, 77 Rio Robles, San Jose CA 95134. This correspondent does not recur in this chain.
  • Context: Securitization of assets.

• 2014-12-19 (executed) / recorded 2014-12-19 — Reel 032644/0787

  • Conveyance: Assignment of Assignor's Interest
  • Assignor: Solarbridge Technologies, Inc.
  • Assignee: Sunpower Corporation
  • Correspondent: David H. Dolkas, Esq., Sunpower Corporation, 77 Rio Robles, San Jose CA 95134. This correspondent appears multiple times in this chain.
  • Context: Acquisition of Solarbridge Technologies, Inc. by Sunpower Corporation.

• 2014-12-19 (executed) / recorded 2014-12-19 — Reel 032644/0788

  • Conveyance: Release by Secured Party
  • Assignor: Silicon Valley Bank
  • Assignee: Solarbridge Technologies, Inc.
  • Correspondent: David H. Dolkas, Esq., Sunpower Corporation, 77 Rio Robles, San Jose CA 95134. This correspondent appears multiple times in this chain.
  • Context: Release of security interest following acquisition.

• 2018-09-10 (executed) / recorded 2018-09-11 — Reel 044955/0342

  • Conveyance: Assignment of Assignors Interest
  • Assignor: Sunpower Corporation
  • Assignee: Enphase Energy, Inc.
  • Correspondent: Peter S. Hecker, Finnegan Henderson Farabow Garrett & Dunner LLP, 901 New York Ave., N.W., Washington DC 20001. This correspondent does not recur in this chain.
  • Context: Acquisition of certain assets of SunPower Corporation by Enphase Energy, Inc.

• 2026-04-21 (executed) / recorded 2026-04-21 — Reel 061141/0064

  • Conveyance: Assignment of Assignor's Interest
  • Assignor: Powerbridge Networks, LLC
  • Assignee: Gridscale Solutions, LLC
  • Correspondent: Joshua R. King, King & SPALDING LLP, 1180 Peachtree Street NE, Atlanta GA 30309. This correspondent does not recur in this chain.
  • Context: Transfer of patent rights between entities.

Timeline diagram

timeline
    title Ownership of US 8279642
    2010 : Assigned to Solarbridge Tech Inc
    2012 : Issued
    2014 : Security interest Silicon Valley Bank
         : Assigned to Sunpower Corp
         : Release by Silicon Valley Bank
    2018 : Assigned to Enphase Energy Inc
    2026 : Assigned to Gridscale Solutions LLC

NPE / troll-pattern signals

1. Shell-entity transfer — unclear. The current assignee, Gridscale Solutions, LLC, has a name that could suggest a shell entity. However, without further information regarding its business operations, product offerings, or physical address details beyond a registered agent, it is unclear if it operates solely as a licensing entity. Powerbridge Networks, LLC, the assignor in the most recent transfer, also has a generic name and could potentially be a shell entity.

2. Known asserter in the chain — not present. Enphase Energy Inc. and SunPower Corporation are operating companies. While some of the entities in the chain have generic names (Powerbridge Networks, LLC and Gridscale Solutions, LLC), they do not match the provided list of known high-frequency plaintiffs.

3. Repeat correspondent across the chain — present. David H. Dolkas, Esq., of Sunpower Corporation, is listed as the correspondent for both the "Assignment of Assignor's Interest" to Sunpower Corporation (Reel 032644/0787, executed 2014-12-19) and the "Release by Secured Party" from Silicon Valley Bank (Reel 032644/0788, executed 2014-12-19). This indicates a consistent legal representation during the acquisition phase.

4. Cascading transfers — not present. The assignments are spaced several years apart (2010, 2014, 2018, 2026), not within a short 24-month window.

5. Pre-litigation transfer — unclear. A CAFC docket search for 2026 did not yield active cases for this patent. Without knowledge of any past or present litigation, it is unclear if any assignment was made within 6 months of an infringement suit.

6. Bankruptcy fire-sale — not present. The assignments to Sunpower Corporation and Enphase Energy, Inc. were part of corporate acquisitions, not bankruptcy proceedings. The final transfer from Powerbridge Networks, LLC to Gridscale Solutions, LLC does not indicate a bankruptcy fire-sale.

7. Privateering — unclear. There's no public information or SEC filings available to suggest that any operating company transferred the patent to an NPE to assert on their behalf.

8. Defensive aggregator (anti-NPE) — not present. The chain does not terminate at any known defensive aggregators like RPX, AST, LOT Network, Unified Patents, or Open Invention Network.

Verdict

NPE — moderate confidence

The most recent assignment to Gridscale Solutions, LLC (Reel 061141/0064, executed and recorded 2026-04-21), combined with the generic naming of the assignor (Powerbridge Networks, LLC) and assignee (Gridscale Solutions, LLC), raises suspicion, though further data would be needed to definitively confirm shell entity status. While there isn't a direct match to a known high-frequency NPE asserter in the chain, the presence of a generic-named entity at the end of the chain, without clear product ties, indicates a potential for NPE activity. The USPTO Assignment Center record can be found at https://assignmentcenter.uspto.gov/.