Confidence: Medium · Source: FCC ULS · As of 2026-09-12
W9MSJ callsign genealogy
Currently held by Johnson, Mark S
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 W9MSJ's current licensee, walking backwards.
- Johnson, Mark SILgranted 2017-06-08cancelled 2017-06-30
Successor callsigns
Callsigns held now by people who previously held W9MSJ.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign W9MSJ, oldest first.
- ESLER, GEORGE A WI2004-01-01 → cancelled 2016-03-16
- Johnson, Mark S IL2017-06-30 active