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Confidence: Medium · Source: FCC ULS · As of 2026-09-12

K1MSR callsign genealogy

Currently held by Rosenthal, 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 K1MSR's current licensee, walking backwards.

  1. W3MSRcancelled· E
    Rosenthal, Mark SMEgranted 2022-06-11cancelled 2022-07-15
  2. KB3YPBcancelled· G
    Rosenthal, Mark SMDgranted 2012-04-25cancelled 2012-05-15

Successor callsigns

Callsigns held now by people who previously held K1MSR.

No current licensee on record previously held this callsign.

← Back to K1MSR License history →