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

WP4MB callsign genealogy

Currently held by OTERO HERNANDEZ, PEDRO J

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 WP4MB's current licensee, walking backwards.

  1. WP4PCDcancelled· T
    MERCADO, JOSE JPRgranted 2014-06-30cancelled 2018-10-16

Successor callsigns

Callsigns held now by people who previously held WP4MB.

  1. KP4TCcancelled· E
    OTERO HERNANDEZ, PEDRO JPRgranted 2013-11-09cancelled 2016-05-13

All historical holders

Every license row we've seen with the callsign WP4MB, oldest first.

  • MORALES, JOSE A PR
    1997-03-13 → cancelled 2009-03-14
  • OTERO HERNANDEZ, PEDRO J PR
    2010-06-22 → cancelled 2013-11-09
  • MERCADO, JOSE J PR
    2018-10-16 active
← Back to WP4MB License history →