Confidence: Medium · Source: FCC ULS · As of 2026-09-12
K4FMS callsign genealogy
Currently held by Swisher III, Fred M
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 K4FMS's current licensee, walking backwards.
- Swisher III, Fred MFLgranted 2022-03-10cancelled 2022-03-29
Successor callsigns
Callsigns held now by people who previously held K4FMS.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign K4FMS, oldest first.
- SMITH, F MICHAEL MI2008-02-01 → cancelled 2020-02-04
- Swisher III, Fred M FL2022-03-29 active