Assignment history

Inventors

The inventors listed on US Patent 7,547,584 are Ko-Ting Chen, Wen-Bin Lu, and Chao-Hu Liang. At the time of the patent application in November 2006, all inventors assigned their rights to their employer, United Microelectronics Corp. There is no public information to suggest any unusual employment patterns following the patent filing.

Original assignee

The original assignee is United Microelectronics Corp. (UMC), a major global semiconductor foundry headquartered in Hsinchu, Taiwan. UMC is an operating company that manufactures integrated circuits for other companies and is one of the world's largest dedicated semiconductor foundries. As a manufacturer of semiconductor devices, UMC undoubtedly developed and shipped products embodying the manufacturing processes described in the patent. The company remains a major, publicly traded, and active entity.

Assignment timeline

• 2006-11-13 (executed) / recorded 2006-11-16 — Reel 018529/0795
  • Conveyance: Assignment
  • Assignor: Ko-Ting Chen, Wen-Bin Lu, Chao-Hu Liang (Inventors)
  • Assignee: United Microelectronics Corp.
  • Correspondent: MIKIO ISHIMARU, The Mclaughlin Law Group, P.C., 26521 Moulton Pkwy, Ste G302, Laguna Hills, CA 92653
  • Context: Standard assignment of invention from employees to their employer at the time of filing.
• 2021-06-18 (executed) / recorded 2021-07-26 — Reel 056991/0292
  • Conveyance: Assignment
  • Assignor: United Microelectronics Corporation
  • Assignee: Marlin Semiconductor Limited
  • Correspondent: James J. DeCarlo, Greenberg Traurig, LLP, 500 Campus Drive, Suite 400, Florham Park, NJ 07932
  • Context: Transfer of the patent from the original operating company to a third-party entity, likely for monetization or assertion purposes.

Timeline diagram

timeline
    title Ownership of US 7,547,584
    2006 : Inventors assign to UMC
    2009 : Patent issued
    2021 : UMC assigns to Marlin Semiconductor
    2025 : IPR filed against patent

NPE / troll-pattern signals

1. Shell-entity transfer — Present. The patent was transferred from an operating manufacturer (United Microelectronics Corp.) to Marlin Semiconductor Limited (Reel 056991/0292, recorded 2021-07-26). Public records identify Marlin Semiconductor as an Irish entity and associate it with Marlin Equity Partners, a private equity firm. It does not appear to be a product-manufacturing company, suggesting it is a special purpose entity for holding and asserting intellectual property.

2. Known asserter in the chain — Present. The current assignee, Marlin Semiconductor Ltd., is the patent owner of record in an inter partes review (IPR) proceeding, IPR2025-01444, initiated by Unified Patents. Unified Patents is an organization that challenges patents it believes are being asserted by non-practicing entities (NPEs). Being the subject of a Unified Patents IPR is a strong indicator that the patent owner is actively asserting the patent.

3. Repeat correspondent across the chain — Not present. The two assignments on record were handled by different law firms.

4. Cascading transfers — Not present. The public record shows a direct transfer from the original assignee to the current assignee.

5. Pre-litigation transfer — Present. The assignment to Marlin Semiconductor Ltd. was recorded on July 26, 2021. This transfer enabled the subsequent assertion activities that led to the filing of IPR2025-01444 in 2025. The transfer was a necessary step to move the patent into an assertion vehicle before any monetization campaign could begin.

6. Bankruptcy fire-sale — Not present. The original assignee, UMC, is a financially healthy, ongoing global enterprise.

7. Privateering — Unclear. The transfer from a major operating company (UMC) to a patent assertion entity (Marlin) fits a common privateering pattern, where the original owner may retain a financial interest in the assertion campaign against its competitors. However, without access to the terms of the sale agreement between UMC and Marlin, this cannot be definitively confirmed.

8. Defensive aggregator (anti-NPE) — Not present. The current assignee is an assertion entity, not a defensive aggregator.

Verdict

NPE — high confidence

The patent was transferred from its original creator, an active semiconductor manufacturer (UMC), to Marlin Semiconductor Ltd., an entity that does not produce products and is associated with a private equity firm (Reel 056991/0292). The patent is currently being challenged in an IPR proceeding (IPR2025-01444) brought by Unified Patents, a strong indicator of active assertion by a non-practicing entity. This combination of a transfer from a manufacturer to a non-operating entity, followed by litigation activity, provides high confidence that the patent is now held for assertion purposes.

A full record of these assignment events can be reviewed at the USPTO Patent Assignment Search database by searching for Patent Number 7547584.