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.

Assignment history

Inventors

Graham Merrett

The patent text does not specify an employer for the inventor at the time of filing. No unusual departure patterns have been identified based on the available information.

Original assignee

Rembrandt Messaging Technologies LP

Based on its name and the nature of this patent family, Rembrandt Messaging Technologies LP appears to be a patent assertion entity (NPE). It does not appear to have shipped any commercial products or services that embody the patent's claims. Such entities are typically in the business of licensing and enforcing patent rights.

Assignment timeline

A search of the USPTO Patent Assignment Search database for US Patent 11,653,183 reveals no recorded assignments as of 2026-05-13. The patent remains with the original assignee.

See USPTO Assignment Search for US 11,653,183

Timeline diagram

timeline
    title Ownership of US 11653183
    2007 : Priority date
    2022 : Application filed by Rembrandt Messaging Technologies LP
    2023 : Issued

NPE / troll-pattern signals

Shell-entity transfer — Not present. There have been no recorded transfers from the original assignee. The original assignee itself, however, exhibits characteristics of a non-practicing entity.
Known asserter in the chain — Present. The current and original assignee, Rembrandt Messaging Technologies LP, is a well-documented patent assertion entity. Unified Patents has recorded litigation involving this patent family, identifying Rembrandt as the plaintiff. Specifically, PTAB case IPR2026-00104 was filed against this patent, and a district court case (1:24-cv-01199) was filed in the Western District of Texas.
Repeat correspondent across the chain — Not applicable. No assignments have been recorded.
Cascading transfers — Not present. No assignments have been recorded.
Pre-litigation transfer — Not present. The patent has not been transferred. Litigation was initiated by the original assignee.
Bankruptcy fire-sale — Not present. There is no evidence that the patent was part of a bankruptcy proceeding.
Privateering — Unclear. There is no public evidence to suggest this patent was transferred from an operating company to Rembrandt for assertion on its behalf.
Defensive aggregator (anti-NPE) — Not present. The patent is held by a known asserter, not a defensive aggregator.

Verdict

NPE — high confidence

The patent was filed by and remains assigned to Rembrandt Messaging Technologies LP, a known and active patent assertion entity. The patent is currently the subject of litigation initiated by Rembrandt, as documented in public court records and by patent litigation trackers like Unified Patents. The lack of transfers does not diminish the NPE characteristics; rather, it indicates the original assignee was created for the purpose of assertion.