Patent 7577417

Assignment history

Inventors, original assignee, and the chain of ownership recorded with the USPTO — including the correspondent attorney who recorded each assignment, since shell-LLC chains often share one repeat-player attorney even when the entity names look unrelated. Surfaces NPE / patent-troll patterns: shell-entity transfers, known asserters in the chain, repeat correspondent fingerprints, pre-litigation assignments, and bankruptcy fire-sales.

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Ownership chain (5)

Asserters network →

Structured records extracted from the assignment-history narrative below. Each entity links to its full ownership-network profile.

  1. 2012-02-15 · recorded 2012-03-12 · reel 027842/0306 · Assignment

    HITACHI, LTD.HITACHI CONSUMER ELECTRONICS CO., LTD.

    internal reorg

  2. 2014-08-26 · recorded 2014-09-08 · reel 033694/0745 · Assignment

    HITACHI CONSUMER ELECTRONICS CO., LTD.HITACHI MAXELL, LTD.

    internal reorg

  3. 2017-10-01 · recorded 2018-01-25 · reel 045142/0208 · Assignment

    HITACHI MAXELL, LTD.MAXELL, LTD.

    internal reorg

  4. 2021-10-01 · recorded 2021-11-29 · reel 058255/0579 · Merger

    MAXELL, LTD.MAXELL, LTD.

    internal reorg

  5. 2021-10-01 · recorded 2021-12-03 · reel 058666/0407 · Change of Name

    MAXELL, LTD.MAXELL, LTD.

    change of name only

Assignment history

Inventors, original assignee, and the chain of ownership recorded with the USPTO — including the correspondent attorney who recorded each assignment, since shell-LLC chains often share one repeat-player attorney even when the entity names look unrelated. Surfaces NPE / patent-troll patterns: shell-entity transfers, known asserters in the chain, repeat correspondent fingerprints, pre-litigation assignments, and bankruptcy fire-sales.

✓ Generated

Inventors

  • Tamotsu Ito (Hitachi Ltd)
  • Katsuki Ikuta (Hitachi Ltd)
  • Masayoshi Kuroda (Hitachi Ltd)
  • Tsukasa Hasegawa (Hitachi Ltd)

No unusual patterns, such as all inventors departing the original assignee within 12 months of filing, are determinable from the provided information.

Original assignee

The original assignee is Hitachi Ltd. Hitachi Ltd. is a multinational conglomerate primarily involved in electronics, electrical equipment, and information technology. It is an operating company and is currently active. The patent itself describes a "cellular phone", which suggests Hitachi Ltd. likely shipped products embodying the claims as a cellular phone manufacturer.

Assignment timeline

  • 2012-02-15 (executed) / recorded 2012-03-12 — Reel 027842/0306
    • Conveyance: Assignment
    • Assignor: HITACHI, LTD.
    • Assignee: HITACHI CONSUMER ELECTRONICS CO., LTD.
    • Correspondent: None listed on provided document.
    • Context: internal reorg
  • 2014-08-26 (executed) / recorded 2014-09-08 — Reel 033694/0745
    • Conveyance: Assignment
    • Assignor: HITACHI CONSUMER ELECTRONICS CO., LTD.
    • Assignee: HITACHI MAXELL, LTD.
    • Correspondent: None listed on provided document.
    • Context: internal reorg
  • 2017-10-01 (executed) / recorded 2018-01-25 — Reel 045142/0208
    • Conveyance: Assignment
    • Assignor: HITACHI MAXELL, LTD.
    • Assignee: MAXELL, LTD.
    • Correspondent: None listed on provided document.
    • Context: internal reorg
  • 2021-10-01 (executed) / recorded 2021-11-29 — Reel 058255/0579
    • Conveyance: Merger
    • Assignor: MAXELL, LTD.
    • Assignee: MAXELL HOLDINGS, LTD.
    • Correspondent: None listed on provided document.
    • Context: internal reorg
  • 2021-10-01 (executed) / recorded 2021-12-03 — Reel 058666/0407
    • Conveyance: Change of Name
    • Assignor: MAXELL HOLDINGS, LTD.
    • Assignee: MAXELL, LTD.
    • Correspondent: None listed on provided document.
    • Context: change of name only

Timeline diagram

timeline
    title Ownership of US 7577417
    2006 : Filed by Hitachi Ltd
    2009 : Issued
    2012 : Assigned to Hitachi Consumer Elect
    2014 : Assigned to Hitachi Maxell Ltd
    2018 : Assigned to Maxell Ltd
    2021 : Merged to Maxell Holdings Ltd
         : Changed name to Maxell Ltd

NPE / troll-pattern signals

  1. Shell-entity transfer — not present. All assignees appear to be operating companies within the Hitachi/Maxell group.
  2. Known asserter in the chain — not present. None of the assignees (Hitachi Ltd, Hitachi Consumer Electronics Co., Ltd., Hitachi Maxell, Ltd., Maxell Holdings, Ltd., Maxell Ltd) are on common NPE lists.
  3. Repeat correspondent across the chain — not present. Correspondent information was not provided in the extracted legal events for this patent for individual assignments.
  4. Cascading transfers — not present. While there were two transfers and a name change within a short period in 2021, these appear to be internal reorganizations/name changes within the Maxell group rather than consecutive transfers through unrelated shell LLCs.
  5. Pre-litigation transfer — unclear. While there is litigation mentioned on Google Patents (e.g., US case filed in Texas Western District Court, IPR2025-01309), the specific dates of these filings in relation to the assignment dates are not precise enough to determine if any assignment occurred within 6 months before the first infringement suit.
  6. Bankruptcy fire-sale — not present. There is no indication of bankruptcy filings for Hitachi Ltd or Maxell Ltd.
  7. Privateering — not present. There is no information to suggest privateering.
  8. Defensive aggregator (anti-NPE) — not present. The chain does not terminate at a known defensive aggregator.

Verdict

Operating-company assertion. The assignment chain clearly shows the patent moving between various entities within the Hitachi and later Maxell corporate group, indicating internal reorganizations and name changes rather than transfers to shell entities. Maxell Ltd, the current assignee, is a known operating company.
Verification: https://assignmentcenter.uspto.gov/

Generated 5/22/2026, 6:46:44 PM