The Department of Infrastructure is to revise its bylaws, to make boat insurance compulsory for those using harbour facilities.
It doesn't know how many vessels are currently uninsured, though.
Infrastructure Minister Phil Gawne provided the information in response to a Tynwald question for written answer from North Douglas MHK Bill Henderson.
Mr Gawne said currently, only boats with agreements to be moored on the pontoons, or those which ply a passenger charter, must have insurance.
Those on a mooring, or which lie alongside a wall or another boat, do not.
Neither do those who store their vessel away from a harbour, or launch on an ad hoc basis.
Mr Gawne says it's hoped the revision of the bylaws will be completed during the current financial year.
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