The Scottish courts appear again to be adding to the clarification of statutory definitions in maritime matters. Though a question of note recently before them may be stated in simple terms, the decision in the case of Global Marine Drilling Co. v. Triton Holdings Ltd 1 is of fundamental importance. Does a mobile offshore drilling unit fall within the definition of “ship” such as to allow arrestment? Lawyers in this field may now benefit, and creditors of the owners and charterers of such assets now rest assured, following the issue of a written opinion addressing this matter, upon which there is little if any specific dicta. The semi-submersible drilling rig Sovereign Explorer was arrested at Invergordon, Scotland in security for claims in a London arbitration. The defender sought recall of the arrestment inter alia as incompetent, the Sovereign Explorer, it said, not being a ship.