Confidence: Medium · Source: FCC ULS · As of 2026-09-12
N9LEO callsign genealogy
Currently held by COSTELLO, LEO 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 N9LEO's current licensee, walking backwards.
- COSTELLO, LEO JINgranted 2003-06-10cancelled 2013-05-29
Successor callsigns
Callsigns held now by people who previously held N9LEO.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign N9LEO, oldest first.
- PRODAN, MICHAEL J IL2001-02-15 → cancelled 2013-05-08
- COSTELLO, LEO J IN2023-03-07 active