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Confidence: Medium · Source: FCC ULS · As of 2026-09-14

K9IZU callsign genealogy

Currently held by Osterman Umbrella Radio Group

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 K9IZU's current licensee, walking backwards.

  1. KD9UQOcancelled
    Osterman Umbrella Radio GroupILgranted 2022-03-24cancelled 2022-04-12

Successor callsigns

Callsigns held now by people who previously held K9IZU.

No current licensee on record previously held this callsign.

All historical holders

Every license row we've seen with the callsign K9IZU, oldest first.

  • MESSINA, JOSEPH R AZ
    2007-12-28 → cancelled 2020-01-24
  • Osterman Umbrella Radio Group IL
    2022-04-12 active