Confidence: Medium · Source: FCC ULS · As of 2026-09-12
W1FS callsign genealogy
Currently held by THIERAUF, STEPHEN 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 W1FS's current licensee, walking backwards.
- THIERAUF, STEPHEN CMAgranted 2006-03-28cancelled 2015-11-10
Successor callsigns
Callsigns held now by people who previously held W1FS.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign W1FS, oldest first.
- MARKLEY, KRIS MA2006-10-19 → cancelled 2013-10-21
- THIERAUF, STEPHEN C MA2025-09-18 active