Master's license
A master's license, or master's ticket, was a document required to be possessed by civilians operating space vessels.

In 2266, interstellar criminal Harcourt Fenton Mudd was charged by Captain James Kirk with operating a vessel without a Master's License. Despite Mudd's claim that he did, in fact, possess one, the ship's computer verified that it was revoked on stardate 1116.4. ()

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de:Kapitänslizenz
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