Assignment history

Inventors

The sole inventor named on US Patent 11520377 is Stephen E. Delaporte. While the patent does not explicitly state his employer at the time of filing, the original assignee and applicant for the patent is Lepton Computing LLC, suggesting he was associated with this entity.

Original assignee

The entity named on the issued patent as the original assignee is Lepton Computing LLC. Lepton Computing LLC states it has been a pioneer in foldable/flexible display mobile devices since 2008 and developed prototypes, claiming its patents predate those of larger smartphone companies. However, despite claims of prototypes and unveiling the "Lepton Flex" as the first foldable smartphone developed in the US, Lepton Computing LLC has not actually released a smartphone product to the market. Several sources refer to Lepton Computing LLC as a "patent troll" or "Non-Practicing Entity" (NPE). Their primary line of business appears to be the development of intellectual property related to foldable devices and subsequent patent assertion. As of April 2026, Lepton Computing LLC is an operating entity, actively asserting patents against Samsung Electronics in the U.S. District Court for the Eastern District of Texas. Lepton Computing LLC reportedly has no public contact details and only two employees.

Assignment timeline

• 2022-10-27 (executed) / recorded 2022-10-31 — Reel 062837/0471
  • Conveyance: Assignment of Assignor's Interest
  • Assignor: Delaporte, Stephen E.
  • Assignee: Lepton Computing LLC
  • Correspondent: Matthew J. DeFrank, 461 Fifth Avenue, 18th Floor, New York, NY, 10017
  • Context: Initial assignment of patent rights from the inventor to the company, Lepton Computing LLC, which was also the applicant.

Timeline diagram

timeline
    title Ownership of US 11520377
    2010 : Priority claimed from earlier application
    2021 : Application filed by Lepton Computing
    2022 : Inventor assigns to Lepton Computing LLC
         : Patent granted
    2026 : Litigation filed by Lepton Computing

NPE / troll-pattern signals

1. Shell-entity transfer

   • Present. Lepton Computing LLC appears to be a licensing-only entity. It claims to have developed prototypes but has not released a product. Multiple sources refer to it as a "patent troll" or "Non-Practicing Entity" (NPE). It reportedly has no public contact details and only two employees.
   • Citation:

2. Known asserter in the chain

   • Unclear. Lepton Computing LLC is actively asserting patents against Samsung. While it functions as an asserter, it is not listed as a "known asserter" in the same manner as large NPEs like Acacia Research or Marathon Patent Group on common directories. However, the search results strongly indicate it acts as a patent asserter.
   • Citation:

3. Repeat correspondent across the chain

   • Not present. Only one assignment record (Reel 062837/0471) is found for this specific patent, so no recurrence of a correspondent can be observed in this chain.

4. Cascading transfers

   • Not present. Only one assignment is recorded for this patent.

5. Pre-litigation transfer

   • Unclear. The patent was assigned from the inventor to Lepton Computing LLC on October 27, 2022 (executed) / October 31, 2022 (recorded) (Reel 062837/0471). Litigation was filed in April 2026, which is well beyond 6 months post-assignment. However, the entity was formed and received patent rights before any product release, suggesting it was established for IP management and assertion.

6. Bankruptcy fire-sale

   • Not present. There is no indication of Lepton Computing LLC being involved in a bankruptcy fire-sale.

7. Privateering

   • Unclear. There is no information to suggest that Lepton Computing LLC is asserting patents on behalf of another operating company.

8. Defensive aggregator (anti-NPE)

   • Not present. The patent is currently being asserted by Lepton Computing LLC, not held by a defensive aggregator.

Verdict

NPE — high confidence
Lepton Computing LLC is acting as a Non-Practicing Entity. The company has not shipped a product embodying the claims despite claiming early prototypes and is actively engaged in patent litigation against Samsung. Multiple news articles refer to Lepton Computing LLC as a "patent troll" or "Non-Practicing Entity", and it reportedly has no public contact details and only two employees. The only recorded assignment (Reel 062837/0471) is from the inventor to this entity, which then proceeded to assert the patent without manufacturing.

USPTO Assignment Center Search for US11520377