Confidence: Medium · Source: FCC ULS · As of 2026-09-14
K5OIC callsign genealogy
Currently held by OBrien, 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 K5OIC's current licensee, walking backwards.
- O'Brien, William JTXgranted 2019-10-30cancelled 2019-11-19
Successor callsigns
Callsigns held now by people who previously held K5OIC.
No current licensee on record previously held this callsign.