Assignment history

Inventors

• Thien Nguyen (Employer: Likely Dryshield, LLC or Solmetex LLC at time of filing, given assignment patterns)
• Tam Thanh Pham (Employer: Likely Dryshield, LLC or Solmetex LLC at time of filing)
• Ethan Nguyen (Employer: Likely Dryshield, LLC or Solmetex LLC at time of filing)
• Lauren Nguyen (Employer: Likely Dryshield, LLC or Solmetex LLC at time of filing)

All inventors assigned their interest in the patent application (US18/376,309) to DRYSHIELD, LLC on the filing date of October 3, 2023. This is a common practice for inventors to assign patent rights to their employer.

Original assignee

The entity named on the issued patent is Solmetex LLC. Solmetex LLC is a company primarily engaged in providing dental waste management solutions, including amalgam separators and dental suction line cleaners. Solmetex LLC ships products embodying the claims through its DryShield brand. Solmetex LLC acquired DryShield in 2023. The company is currently operating.

Assignment timeline

• 2023-10-03 (executed) / recorded 2023-10-04 — Reel 006450/0675

  • Conveyance: ASSIGNMENT
  • Assignor: PHAM, TAM THANH; NGUYEN, ETHAN; NGUYEN, LAUREN; NGUYEN, THIEN
  • Assignee: DRYSHIELD, LLC
  • Correspondent: LINDSEY E. MILLER, ESQ., KNOBBE MARTENS, 2040 MAIN STREET, 14TH FLOOR, IRVINE, CA 92614. This correspondent recurs in this chain.
  • Context: Inventors assigned their rights in the patent application to Dryshield, LLC, likely their employer or an affiliated entity.

• 2023-10-03 (executed) / recorded 2023-10-04 — Reel 006450/0680

  • Conveyance: ASSIGNMENT
  • Assignor: DRYSHIELD, LLC
  • Assignee: SOLMETEX, LLC
  • Correspondent: LINDSEY E. MILLER, ESQ., KNOBBE MARTENS, 2040 MAIN STREET, 14TH FLOOR, IRVINE, CA 92614. This correspondent recurs in this chain.
  • Context: Transfer of ownership from Dryshield, LLC to Solmetex, LLC, consistent with Solmetex's acquisition of Dryshield.

• 2025-03-17 (executed) / recorded 2025-03-18 — Reel 006764/0055

  • Conveyance: SECURITY AGREEMENT
  • Assignor: DRYSHIELD, LLC; IMPLADENT, LTD.; SOLMETEX, LLC; STERISIL, INC.
  • Assignee: CHURCHILL AGENCY SERVICES LLC, AS ADMINISTRATIVE AGENT
  • Correspondent: WILLIAM S. PATTISON, ESQ., DUANE MORRIS LLP, 30 SOUTH 17TH STREET, PHILADELPHIA, PA 19103-7396.
  • Context: This is a security interest, not a change of ownership, likely collateral for a loan involving Solmetex and its related entities.

Timeline diagram

timeline
    title Ownership of US 12167948
    2023-10-03 : Inventors assign to DRYSHIELD, LLC
               : DRYSHIELD, LLC assigns to SOLMETEX, LLC
    2024-12-17 : Patent granted to SOLMETEX, LLC
    2025-03-17 : Security Agreement with CHURCHILL AGENCY SERVICES LLC

NPE / troll-pattern signals

1. Shell-entity transfer — not present. The transfers involve operating companies (Dryshield, LLC and Solmetex, LLC). Solmetex acquired Dryshield, and Dryshield is a brand under Solmetex.
2. Known asserter in the chain — not present. Neither Solmetex LLC nor Dryshield LLC are identified as known patent asserters.
3. Repeat correspondent across the chain — unclear. Lindsey E. Miller, ESQ. of Knobbe Martens is listed as the correspondent for both assignments on 2023-10-04 (Reel 006450/0675 and 006450/0680). While this represents a recurrence within the chain, Knobbe Martens is a well-regarded intellectual property firm that serves many operating companies, and these transfers appear to be part of a legitimate corporate restructuring/acquisition, not indicative of NPE activity.
4. Cascading transfers — not present. There are two transfers on the same day, which are closely related (inventors to Dryshield, then Dryshield to Solmetex) and are consistent with an acquisition and internal ownership clarification, not the typical unrelated shell entity transfers.
5. Pre-litigation transfer — not present. The assignments were executed and recorded on October 3-4, 2023. The patent was granted on December 17, 2024. The first family litigation was filed on February 18, 2025, which is more than 6 months after the assignments.
6. Bankruptcy fire-sale — not present. No evidence of bankruptcy for the assignors.
7. Privateering — not present. The acquisition of Dryshield by Solmetex suggests a standard business integration, not a privateering arrangement.
8. Defensive aggregator (anti-NPE) — not present. The chain does not terminate at a known defensive aggregator.

Verdict

Operating-company assertion.
The assignment record indicates a straightforward chain of title from the inventors to Dryshield, LLC, and then to Solmetex, LLC, all executed and recorded on the same day (2023-10-03/04, Reel 006450/0675 and 006450/0680). Solmetex LLC is an operating company that acquired Dryshield and markets products related to the patent. The security agreement with Churchill Agency Services LLC is a financing arrangement, not a change of ownership. There are no signals indicative of NPE activity in this patent's assignment history.

USPTO Assignment Center search for US12167948: https://assignmentcenter.uspto.gov/patent/index.html?cn=[12167948](/patent/12167948)