Confidence: Medium · Source: FCC ULS · As of 2026-09-12
W5OIL callsign genealogy
Currently held by Haase, Mark C
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 W5OIL's current licensee, walking backwards.
- Haase, Mark CTXgranted 2007-05-03cancelled 2007-05-22
Successor callsigns
Callsigns held now by people who previously held W5OIL.
No current licensee on record previously held this callsign.