The Economic Development Minister says charging the RNLI £250 to use the TT initials only covers his department's legal costs.
The DED's facing a storm of criticism on Facebook after asking the volunteer lifesaving charity to pay to use the TT on fundraising badges.
Laurence Skelly says it's vital the department defends its trademark, otherwise it might face losing it in a future dispute.
But he says it is not profiting at the expense of lifeboat stations and crews:
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Emergency powers used to fell trees
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