Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KC4OWL callsign genealogy
Currently held by MARTINOLICH, WILLIAM J
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 KC4OWL's current licensee, walking backwards.
Successor callsigns
Callsigns held now by people who previously held KC4OWL.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign KC4OWL, oldest first.
- MARTINOLICH, WILLIAM J FL2000-01-07 → cancelled 2012-03-07
- Roberts, Esther L TN2025-12-09 active