Confidence: Medium · Source: FCC ULS · As of 2026-09-12
W4PTY callsign genealogy
Currently held by CASTILLO, AMBROSIO
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 W4PTY's current licensee, walking backwards.
- CASTILLO, AMBROSIOTXgranted 2023-07-25cancelled 2025-07-08
Successor callsigns
Callsigns held now by people who previously held W4PTY.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign W4PTY, oldest first.
- OLEARY, ARTHUR J SC2011-03-31 → cancelled 2023-07-12
- CASTILLO, AMBROSIO TX2025-07-08 active