Assignment history

Inventors

• Charles Cameron Lindquist: Employer at the time of filing is not explicitly stated in the patent or search results.
• Timothy John Lindquist: Employer at the time of filing is not explicitly stated in the patent or search results.

The patent itself does not list employer information for the inventors. There is no unusual pattern of inventors departing an original assignee within 12 months, as the initial assignment from the inventors occurred after the filing date.

Original assignee

The entity named on the issued patent is Portus Singapore Pte Ltd.

Portus Singapore Pte Ltd's principal activity is "INTERNET ACCESS PROVIDERS, INCLUDE ISPS" with "OTHER HOLDING COMPANIES" as a secondary activity. They were incorporated in November 2002. Portus, as an overall entity, claims to be "the original creator of the smart home" and "pioneered the technology for viewing your home when you are away, as well as understanding and managing household energy use". They state they have developed "valuable and industry-leading smart home systems, including IP video surveillance solutions for use in homes and offices" under the protection of this patent. They also mention licensing the technology to Apple, Cisco, and Comcast.

Portus Singapore Pte Ltd is currently operating and has been actively involved in patent litigation, indicating its role in asserting its patent portfolio.

Assignment timeline

The USPTO Assignment Center search for US8914526 (as of 2026-06-01) reveals the following assignments:

• 2001-12-31 (executed) / recorded 2002-01-28 — Reel 008581/0212

  • Conveyance: Assignment
  • Assignor: Charles Cameron Lindquist
  • Assignee: Portus Pty Limited
  • Correspondent: BLAKELY SOKOLOFF TAYLOR & ZAFMAN LLP (formerly Blakely, Sokoloff, Taylor & Zafman), Los Angeles, CA.
  • Context: Inventor assigned his interest to an Australian entity.

• 2001-12-31 (executed) / recorded 2002-01-28 — Reel 008581/0225

  • Conveyance: Assignment
  • Assignor: Timothy John Lindquist
  • Assignee: Portus Pty Limited
  • Correspondent: BLAKELY SOKOLOFF TAYLOR & ZAFMAN LLP (formerly Blakely, Sokoloff, Taylor & Zafman), Los Angeles, CA. This correspondent also appears on the previous record for Charles Cameron Lindquist.
  • Context: Inventor assigned his interest to an Australian entity.

• 2005-09-08 (executed) / recorded 2005-09-29 — Reel 016790/0040

  • Conveyance: Assignment
  • Assignor: PORTUS PTY LIMITED
  • Assignee: PORTUS SINGAPORE PTE LTD
  • Correspondent: BLAKELY, SOKOLOFF, TAYLOR & ZAFMAN LLP, Los Angeles, CA. This correspondent recurs in this chain.
  • Context: Transfer from Australian entity to Singaporean entity, likely an internal corporate reorganization.

• 2014-10-21 (executed) / recorded 2014-10-21 — Reel 033320/0672

  • Conveyance: Assignment
  • Assignor: Timothy John Lindquist
  • Assignee: PORTUS SINGAPORE PTE LTD
  • Correspondent: BLAKELY SOKOLOFF TAYLOR & ZAFMAN LLP, Los Angeles, CA. This correspondent recurs in this chain.
  • Context: Inventor assigned his interest directly to the current assignee, likely a corrective or confirming assignment after the primary assignment to Portus Pty Limited.

Timeline diagram

timeline
    title Ownership of US 8914526
    1999 : Filed by Portus Singapore
    2001 : Inventor Charles Lindquist assigns to Portus Pty Ltd
         : Inventor Timothy Lindquist assigns to Portus Pty Ltd
    2005 : Portus Pty Ltd assigns to Portus Singapore Pte Ltd
    2014 : Inventor Timothy Lindquist assigns to Portus Singapore
         : Patent issued
    2019 : Expired - Fee Related
    2022 : Litigation begins

NPE / troll-pattern signals

1. Shell-entity transfer — Unclear. Portus Singapore Pte Ltd's primary activity is "INTERNET ACCESS PROVIDERS, INCLUDE ISPS" and "OTHER HOLDING COMPANIES". While "holding companies" can be a shell indicator, Portus claims to have developed smart home systems and licensed technology. The company appears to have a legitimate business origin in smart home technology development and licensing.
2. Known asserter in the chain — Present. Portus Singapore Pte Ltd and Portus Pty Ltd are documented as patent asserters in multiple litigations, including against Trane Technologies, Lennox International, Amazon, Samsung, Haier Group, and Daikin Industries. Unified Patents explicitly identifies Portus Singapore Pte Ltd as an NPE.
3. Repeat correspondent across the chain — Present. BLAKELY SOKOLOFF TAYLOR & ZAFMAN LLP (or its earlier iteration Blakely, Sokoloff, Taylor & Zafman) of Los Angeles, CA, is listed as the correspondent for all four recorded assignments (Reel 008581/0212, Reel 008581/0225, Reel 016790/0040, and Reel 033320/0672). This firm handled the initial assignments from the inventors and the subsequent transfer between Portus entities.
4. Cascading transfers — Not present. The transfers occurred with significant time gaps (2001, 2005, 2014).
5. Pre-litigation transfer — Not present. The patent was issued in 2014, and the last assignment was in 2014. Litigation activity is observed starting around 2022, well after the last assignment.
6. Bankruptcy fire-sale — Not present. There is no indication of the original assignee or any subsequent assignee going through bankruptcy proceedings related to these assignments.
7. Privateering — Unclear. While Portus claims to have licensed its technology to companies like Apple, Cisco, and Comcast, there is no explicit evidence in the provided text or search results to suggest that Portus is asserting this patent on behalf of an operating company against its competitors in a privateering arrangement.
8. Defensive aggregator (anti-NPE) — Not present. The chain ends with Portus Singapore Pte Ltd, which is actively asserting the patent, not neutralizing it.

Verdict

NPE — high confidence. The presence of Portus Singapore Pte Ltd, identified as a known NPE by Unified Patents, combined with their extensive litigation history across various district courts against numerous companies (e.g., Trane, Lennox, Amazon, Samsung, Haier, Daikin), strongly indicates an NPE pattern. The recurring correspondent, BLAKELY SOKOLOFF TAYLOR & ZAFMAN LLP, across all assignments further supports a coordinated, long-term strategy of patent management and assertion for this patent family (Reel 008581/0212, Reel 008581/0225, Reel 016790/0040, Reel 033320/0672).

USPTO Assignment Center search for US8914526: https://assignmentcenter.uspto.gov/patents/8914526