A Delivery Order (D/O) is used for the partial transfer of goods in transit. It can be issued by a holder of the bill of lading and by an owner of the vessel. If it is issued by the holder of the B/L, it instructs the delivery of the goods to the owner of the vessel or the cargo handler at the port of discharge. The holder of the D/O cannot claim delivery of the goods unless the B/L owner or cargo handler has endorsed the document, except in certain cases. If it is issued by the owner of the vessel, it instructs the captain or their agent to deliver the goods, and the holder of the D/O can claim delivery of the goods to the captain. A D/O is a type of instruction document and is different from a B/O, which represents a transportation claim.
Source : National Logistics Information Center of Korea