Confidence: Medium · Source: FCC ULS · As of 2026-09-14
KO4USR callsign genealogy
Currently held by Holley, Michael
The FCC publishes a previous_call_sign on
every amateur license — a self-link to the licensee's prior callsign.
Following those links produces the chain below.
Previous callsigns
Older callsigns held by KO4USR's current licensee, walking backwards.
- Holley, MichaelUTgranted 2026-05-22cancelled 2026-06-13
Successor callsigns
Callsigns held now by people who previously held KO4USR.
- Wasden, Kathy LGAgranted 2023-05-06
All historical holders
Every license row we've seen with the callsign KO4USR, oldest first.
- Wasden, Kathy L GA2021-11-15 → cancelled 2023-05-06
- Holley, Michael UT2026-06-13 active