Confidence: Medium · Source: FCC ULS · As of 2026-09-12
W4JMB callsign genealogy
Currently held by Butterworth, Joseph 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 W4JMB's current licensee, walking backwards.
- Butterworth, Joseph MGAgranted 2005-06-22cancelled 2013-05-10
Successor callsigns
Callsigns held now by people who previously held W4JMB.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign W4JMB, oldest first.
- PHILLIPS, WILLIAM R TN1997-04-01 → cancelled 2009-04-02
- Butterworth, Joseph M GA2023-03-10 active