Assignment history

Inventors

• Brandon N. Hinderliter: Employed by U.S. Well Services, LLC at the time of filing.
• Jared Oehring: Employed by U.S. Well Services, LLC at the time of filing.

No unusual patterns were determinable from the provided information regarding inventors departing the original assignee.

Original assignee

The entity named on the issued patent is U.S. Well Services LLC. They are a provider of electric hydraulic fracturing services and actively shipped products embodying the claims of US11211801. U.S. Well Services LLC was acquired by ProFrac Holding Corp. in 2023 or 2024, as indicated by its inclusion as an assignor alongside ProFrac Services, LLC in a security agreement recorded in January 2024. Therefore, U.S. Well Services LLC currently operates as a subsidiary of ProFrac Holding Corp.

Assignment timeline

The following is a chronological list of recorded assignments for US Patent 11211801 as retrieved from the USPTO Assignment Center.

• 2021-01-06 (executed) / recorded 2021-01-28 — Reel 056461/0219

  • Conveyance: Assignment
  • Assignor: HINDERLITER, BRANDON N.
  • Assignee: U.S. Well Services, LLC
  • Correspondent: BASS, DAVID P. (BASS PATENT LAW, P.C.), 1926 W. Gray St., Suite 244, Houston, TX 77019. (This correspondent recurs in this chain.)
  • Context: Inventor assignment to the original assignee.

• 2021-06-30 (executed) / recorded 2021-07-06 — Reel 057065/0805

  • Conveyance: Security Interest
  • Assignor: U.S. Well Services, LLC
  • Assignee: WILMINGTON SAVINGS FUND SOCIETY, FSB
  • Correspondent: RAGHAVAN, RAJA (PATENT CAPITAL GROUP), 1341 E. MAIN ST., SUITE C-1, ST. CHARLES, IL 60174
  • Context: Grant of a security interest by the original assignee for financing.

• 2021-11-16 (executed) / recorded 2021-11-23 — Reel 057497/0050

  • Conveyance: Assignment
  • Assignor: OEHRING, JARED
  • Assignee: U.S. Well Services, LLC
  • Correspondent: BASS, DAVID P. (BASS PATENT LAW, P.C.), 1926 W. Gray St., Suite 244, Houston, TX 77019. (This correspondent recurs in this chain.)
  • Context: Inventor assignment to the original assignee.

• 2022-11-02 (executed) / recorded 2022-11-08 — Reel 059639/0713

  • Conveyance: Security Interest
  • Assignor: U.S. Well Services, LLC
  • Assignee: PIPER SANDLER FINANCE LLC
  • Correspondent: NOT PROVIDED
  • Context: Grant of a security interest by the original assignee for financing.

• 2022-12-16 (executed) / recorded 2022-12-20 — Reel 059873/0974

  • Conveyance: Security Interest
  • Assignor: U.S. WELL SERVICE HOLDINGS, LLC; U.S. Well Services, LLC; USWS FLEET 10, LLC; USWS FLEET 11, LLC; USWS HOLDINGS LLC
  • Assignee: JPMORGAN CHASE BANK, N.A.
  • Correspondent: MARIN, MARTHA M. (JPMORGAN CHASE BANK, N.A.), 270 PARK AVE, NEW YORK, NY 10017
  • Context: Grant of a security interest by the original assignee and related entities for financing.

• 2023-12-21 (executed) / recorded 2023-12-27 — Reel 062137/0861

  • Conveyance: Release
  • Assignor: WILMINGTON SAVINGS FUND SOCIETY, FSB, AS COLLATERAL AGENT
  • Assignee: U.S. Well Services, LLC
  • Correspondent: AUSTIN, MICHAEL A. (FTS INTERNATIONAL SERVICES, LLC), 100 E. F.I.S. BLVD, FORT WORTH, TX 76140. (This correspondent recurs in this chain.)
  • Context: Release of a previously granted security interest.

• 2024-01-03 (executed) / recorded 2024-01-08 — Reel 062180/0178

  • Conveyance: Intellectual Property Security Agreement
  • Assignor: BEST PUMP AND FLOW, LLC; FTS INTERNATIONAL SERVICES, LLC; PROFRAC SERVICES, LLC; U.S. WELL SERVICES HOLDINGS, LLC; U.S. Well Services, LLC
  • Assignee: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
  • Correspondent: AUSTIN, MICHAEL A. (PROFRAC SERVICES, LLC), 100 E F I S BLVD, FORT WORTH, TX 76140. (This correspondent recurs in this chain.)
  • Context: Grant of a security interest by ProFrac entities, including U.S. Well Services, LLC, following the acquisition of U.S. Well Services, LLC by ProFrac Holding Corp.

Timeline diagram

timeline
    title Ownership of US 11211801
    2019 : Filed by US Well Services LLC
    2021 : Issued
         : Inventor Hinderliter assigned
         : Security interest to Wilmington
         : Inventor Oehring assigned
    2022 : Security interest to Piper Sandler
         : Security interest to JPMorgan
    2023 : Wilmington security interest released
    2024 : IP Security to US Bank Trust Co.

NPE / troll-pattern signals

1. Shell-entity transfer — Not present. The transfers primarily involve the original operating company (U.S. Well Services, LLC), financial institutions for security interests, and entities related to the acquiring operating company (ProFrac Holding Corp.).
2. Known asserter in the chain — Not present. The assignees are operating companies or financial institutions, none of which are recognized as known patent asserters on public NPE lists.
3. Repeat correspondent across the chain — Present. David P. Bass of Bass Patent Law, P.C. appears as the correspondent for both inventor assignments to U.S. Well Services, LLC (Reel 056461/0219 recorded 2021-01-28 and Reel 057497/0050 recorded 2021-11-23). Michael A. Austin, associated with FTS International Services, LLC and ProFrac Services, LLC, is the correspondent for the security interest release (Reel 062137/0861 recorded 2023-12-27) and the subsequent Intellectual Property Security Agreement (Reel 062180/0178 recorded 2024-01-08). This indicates continuity in legal representation, rather than an NPE pattern, as the latter correspondent is associated with the acquiring operating company.
4. Cascading transfers — Not present. The records show inventor assignments and multiple security interests over several years, but not rapid, consecutive transfers of title through chained LLCs.
5. Pre-litigation transfer — Not present. The US case filed in Texas Eastern District Court (2:25-cv-00522) was filed in 2025. The last significant transfer-like event (Intellectual Property Security Agreement) was executed on 2024-01-03 and recorded on 2024-01-08 (Reel 062180/0178), which is well over six months before the 2025 litigation filing.
6. Bankruptcy fire-sale — Not present. The acquisition of U.S. Well Services, LLC by ProFrac Holding Corp. does not appear to have been a bankruptcy fire-sale based on the provided assignment records.
7. Privateering — Unclear. While the patent is currently controlled by an operating company (ProFrac Holding Corp. via its subsidiary U.S. Well Services, LLC) that might assert it against competitors, the records do not provide explicit evidence to categorize this as "privateering" where an operating company transfers to an NPE to assert on its behalf.
8. Defensive aggregator (anti-NPE) — Not present. The chain does not terminate at a known defensive aggregator.

Verdict

Operating-company assertion

The patent originated with U.S. Well Services, LLC, an operating company that developed and marketed products embodying the claims. While the company was later acquired by ProFrac Holding Corp., this represents a consolidation within the operating industry rather than a transfer to a non-practicing entity. The current litigation in the Texas Eastern District Court (2:25-cv-00522) would likely be an assertion by the operating company (ProFrac/U.S. Well Services) against a competitor. The assignment records primarily reflect inventor assignments and security interests, not transfers to shell entities.

USPTO Assignment Center search for US11211801: https://assignmentcenter.uspto.gov/