Treasury Minister Chris Thomas says he doesn't know how much money medicinal cannabis has put in the government's coffers.
In the house of Kerys this week he faced questions from Arbory, Castletown and Malew MHK Jason Moorhouse about cash raised by the industry.
Mr Thomas said the medical drug is zero-rated for VAT and it was impossible to see how much income tax the industry had paid.
But he said he doubted the Isle of Man was losing out because the UK offered cheaper licences:
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