Confidence: Medium · Source: FCC ULS · As of 2026-09-14
WP4ISR callsign genealogy
Currently held by SANCHEZ, IVAN G
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 WP4ISR's current licensee, walking backwards.
Successor callsigns
Callsigns held now by people who previously held WP4ISR.
- SANCHEZ, IVAN GPRgranted 2022-07-02
All historical holders
Every license row we've seen with the callsign WP4ISR, oldest first.
- RIVERA, JUAN C PR1990-02-06 → cancelled 2002-03-07
- SANCHEZ, IVAN G PR2022-07-02 → cancelled 2022-11-23