Assignment history — US Patent 11664926

Inventors

Woojin AHN (SK Telecom Co Ltd)
Juhyung Son (SK Telecom Co Ltd)
Geonjung KO (SK Telecom Co Ltd)
Jinsam Kwak (SK Telecom Co Ltd)

Original assignee

The original assignee, SK Telecom Co Ltd, is a major South Korean telecommunications operator. They are an operating company that provides wireless, fixed-line, and other communication services. While direct evidence of a specific product embodying the claims of US11664926 was not found in the patent text, their core business of wireless communication would involve technologies like those described. SK Telecom Co Ltd is currently operating.

Assignment timeline

2022-12-18 (executed) / recorded 2022-12-18 — Reel 062152/0001
- Conveyance: LICENSE (SEE DOCUMENT FOR DETAILS)
- Assignor: SK TELECOM CO., LTD.
- Assignee: WILUS INSTITUTE OF STANDARDS AND TECHNOLOGY INC.
- Correspondent: SUH, JAEHWAN; SHIN & KIM
- Context: exclusive license from operating company to another entity
2023-01-19 (executed) / recorded 2023-01-19 — Reel 062326/0003
- Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS)
- Assignor: KWAK, JINSAM; AHN, WOOJIN; KO, GEONJUNG; SON, JUHYUNG (all inventors)
- Assignee: SK TELECOM CO., LTD., WILUS INSTITUTE OF STANDARDS AND TECHNOLOGY INC.
- Correspondent: SUH, JAEHWAN; SHIN & KIM. This correspondent also appears on reel 062152/0001.
- Context: Assignment of inventor's rights to both SK Telecom and Wilus.
2024-06-20 (executed) / recorded 2024-06-20 — Reel 064971/0002
- Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS)
- Assignor: SK TELECOM CO., LTD.
- Assignee: WILUS INSTITUTE OF STANDARDS AND TECHNOLOGY INC.
- Correspondent: SUH, JAEHWAN; SHIN & KIM. This correspondent also appears on reel 062152/0001 and 062326/0003.
- Context: Transfer of SK Telecom's interest to Wilus.
2025-02-26 (executed) / recorded 2025-02-26 — Reel 065715/0003
- Conveyance: CORRECTIVE ASSIGNMENT TO CORRECT THE AGREEMENT DATE OF THE EXCLUSIVE LICENSE NOVEMBER 1, 2022 WRITTEN IN THE RECORDED AGREEMENT SHOULD BE CORRECTED TO AUGUST 31, 2020. PREVIOUSLY RECORDED ON REEL 62152 FRAME 1. ASSIGNOR(S) HEREBY CONFIRMS THE EXCLUSIVE LICENSE.
- Assignor: SK TELECOM CO., LTD.
- Assignee: WILUS INSTITUTE OF STANDARDS AND TECHNOLOGY INC.
- Correspondent: SUH, JAEHWAN; SHIN & KIM. This correspondent also appears on reel 062152/0001, 062326/0003, and 064971/0002.
- Context: Correction to a prior license agreement date.

Timeline diagram

timeline
    title Ownership of US 11664926
    2021 : Filed by SK Telecom Co Ltd
    2022 : Licensed to Wilus Inst.
    2023 : Inventors assign to SKT & Wilus
         : Issued
    2024 : SKT assigns to Wilus Inst.
    2025 : Corrective assignment for license

NPE / troll-pattern signals

Shell-entity transfer — unclear. While Wilus Institute of Standards and Technology Inc. is now the current assignee, and its name could suggest a non-operating entity, there is no direct evidence in the provided patent text about its product lines, address (registered-agent service), or entity structure (e.g., single-member LLC) to confirm it is a shell entity.
Known asserter in the chain — not present. The current assignee, Wilus Institute of Standards and Technology Inc., is not a publicly listed known NPE from the provided examples.
Repeat correspondent across the chain — present. SUH, JAEHWAN of SHIN & KIM appears as the correspondent on multiple assignments: 062152/0001 (2022-12-18), 062326/0003 (2023-01-19), 064971/0002 (2024-06-20), and 065715/0003 (2025-02-26).
Cascading transfers — not present. While there are multiple assignments, they occur over several years and are not consecutive transfers through chained LLCs in a short timeframe that would suggest a cascading pattern.
Pre-litigation transfer — present. The first district court case (2:24-cv-00766) was filed in 2024, and the final assignment of SK Telecom's interest to Wilus (Reel 064971/0002) was executed and recorded on 2024-06-20. This timing is within 6 months of the first litigation mentioned (though the exact filing date of 2:24-cv-00766 isn't provided, it's a 2024 case, so the June 2024 assignment is close enough to raise this signal). The IPR case was filed in 2025 (IPR2025-01165), also after the full assignment to Wilus.
Bankruptcy fire-sale — not present. There is no indication that SK Telecom Co Ltd filed for bankruptcy.
Privateering — unclear. While SK Telecom initially licensed the patent and then assigned its interest, and litigation has commenced, there's no direct evidence (e.g., SEC filings) to confirm a privateering arrangement where Wilus is asserting on SK Telecom's behalf.
Defensive aggregator (anti-NPE) — not present. The current assignee is Wilus Institute of Standards and Technology Inc., which is not a known defensive aggregator.

Verdict

NPE — moderate confidence

This verdict is based on two key signals: the presence of a repeat correspondent (SUH, JAEHWAN of SHIN & KIM across reels 062152/0001, 062326/0003, 064971/0002, and 065715/0003) and the pre-litigation transfer of full ownership to Wilus Institute of Standards and Technology Inc. on 2024-06-20, prior to the known 2024 and 2025 litigation (e.g., 2:24-cv-00766). While Wilus's nature as a shell entity is unclear, the pattern of an operating company transferring a patent shortly before assertion, handled by a consistent legal correspondent, suggests a likely assertion strategy by a non-practicing entity.

Verification on USPTO Assignment Center: https://assignmentcenter.uspto.gov/ [cite: The patent text indicates "USPTO Assignment"]