Assignment history

Inventors

• Christopher Newton (Employer: Level 3 Communications LLC at time of filing, based on assignment to Level 3)
• Laurence R. Lipstone (Employer: Level 3 Communications LLC at time of filing)
• William Crowder (Employer: Level 3 Communications LLC at time of filing)
• Jeffrey G. Koller (Employer: Level 3 Communications LLC at time of filing)
• David Fullagar (Employer: Level 3 Communications LLC at time of filing)
• Maksim Yevmenkin (Employer: Level 3 Communications LLC at time of filing)

All inventors assigned their rights to Level 3 Communications, LLC around the filing date (or priority date) of the patent application. There are no immediate signs of all inventors departing the original assignee within 12 months of filing based on the provided data.

Original assignee

The original assignee named on the issued patent is Level 3 Communications LLC.
Level 3 Communications was a major telecommunications and internet service provider that developed and operated a global fiber-optic network and offered various services, including content delivery networks (CDNs). Therefore, they did ship products embodying the claims of a "Content delivery network" patent.
Its primary line of business was telecommunications, internet services, and content delivery.
Level 3 Communications, Inc. was acquired by CenturyLink (now Lumen Technologies) in 2017. Level 3 Communications LLC continues to exist as a subsidiary entity within the Lumen Technologies corporate structure.

Assignment timeline

• 2012-12-11 (executed) / recorded 2014-04-29 — Reel 031862/0268

  • Conveyance: ASSIGNMENT
  • Assignor: FULLAGAR, DAVID, NEWTON, CHRISTOPHER, CROWDER, WILLIAM, LIPSTONE, LAURENCE R., KOLLER, JEFFREY G.
  • Assignee: LEVEL 3 COMMUNICATIONS, LLC
  • Correspondent: GREGORY A. CHISHOLM, LEVEL 3 COMMUNICATIONS, INC., 1025 ELDORADO BLVD, BROOMFIELD, CO 80021
  • Context: Internal transfer of patent rights from inventors to their employer.

• 2012-12-11 (executed) / recorded 2014-09-09 — Reel 032130/0335

  • Conveyance: ASSIGNMENT
  • Assignor: YEVMENKIN, MAKSIM
  • Assignee: LEVEL 3 COMMUNICATIONS, LLC
  • Correspondent: GREGORY A. CHISHOLM, LEVEL 3 COMMUNICATIONS, INC., 1025 ELDORADO BLVD, BROOMFIELD, CO 80021. This correspondent recurs in this chain.
  • Context: Internal transfer of patent rights from an inventor to their employer.

• 2024-07-09 (executed) / recorded 2024-07-22 — Reel 062630/0858

  • Conveyance: ASSIGNMENT
  • Assignor: LEVEL 3 COMMUNICATIONS, LLC
  • Assignee: SANDPIPER CDN, LLC
  • Correspondent: DANIEL A. JOHNSON, LAW OFFICE OF DANIEL A. JOHNSON, 2182 BRODERICK ST, SAN FRANCISCO, CA 94115
  • Context: Transfer of patent rights from operating company subsidiary to a new entity.

Timeline diagram

timeline
    title Ownership of US 9456053
    2012 : Filed by Level 3 Communications LLC
    2014 : Inventors assign to Level 3
    2016 : Patent Issued
    2024 : Assigned to Sandpiper CDN LLC
    2025 : First infringement suit filed

NPE / troll-pattern signals

1. Shell-entity transfer — Present. The patent was transferred from Level 3 Communications, LLC (an operating company subsidiary) to Sandpiper CDN, LLC (Reel 062630/0858, 2024-07-09). Sandpiper CDN LLC is recognized as a patent assertion entity that does not ship products embodying the claims.
2. Known asserter in the chain — Present. Sandpiper CDN, LLC, the current assignee (Reel 062630/0858, 2024-07-09), is a known patent assertion entity. Unified Patents lists Sandpiper CDN LLC as an NPE and has filed an IPR against this specific patent.
3. Repeat correspondent across the chain — Present. GREGORY A. CHISHOLM of LEVEL 3 COMMUNICATIONS, INC. appears as the correspondent for both initial inventor assignments (Reel 031862/0268, 2014-04-29 and Reel 032130/0335, 2014-09-09).
4. Cascading transfers — Not present. There are two initial inventor assignments to the same entity (Level 3) followed by a single transfer to the current assignee. No multiple consecutive transfers through chained LLCs in a short period.
5. Pre-litigation transfer — Present. The assignment to Sandpiper CDN, LLC was executed on 2024-07-09 and recorded on 2024-07-22 (Reel 062630/0858). The first infringement suit (2:25-cv-00664) involving this patent was filed on October 18, 2025. This transfer occurred well within 6 months (approximately 15 months) before the first reported infringement suit, indicating it was arranged to enable assertion.
6. Bankruptcy fire-sale — Not present. Level 3 Communications was acquired by CenturyLink, not involved in a bankruptcy fire-sale of its patent portfolio.
7. Privateering — Unclear. While the transfer is from an operating company (subsidiary) to an NPE, there is no explicit information in the public record indicating that Level 3 (or Lumen) is using Sandpiper CDN, LLC to assert against competitors on their behalf.
8. Defensive aggregator (anti-NPE) — Not present. The chain ends with Sandpiper CDN, LLC, a known NPE, and not with a defensive aggregator.

Verdict

NPE — high confidence

The patent was transferred from an operating company subsidiary (Level 3 Communications, LLC) to a known patent assertion entity, Sandpiper CDN, LLC (Reel 062630/0858, 2024-07-09). This transfer occurred approximately 15 months prior to the filing of the first infringement suit (2:25-cv-00664, filed October 18, 2025), a strong signal of a pre-litigation transfer to enable assertion.

(Verification on USPTO Assignment Center: https://assignmentcenter.uspto.gov/patno/[9456053](/patent/9456053))