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

W1BTO callsign genealogy

Currently held by SWIFT, MICHAEL B

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 W1BTO's current licensee, walking backwards.

  1. N1SFLcancelled· G
    SWIFT, MICHAEL BNHgranted 2004-04-19cancelled 2008-12-30

Successor callsigns

Callsigns held now by people who previously held W1BTO.

No current licensee on record previously held this callsign.