Sea bill of lading is negotiable. Through the form of transfer of bill of lading, the sale or transfer of the goods contained in it means that the ownership of the goods is transferred from the original holder of the bill of lading to the receiver of the bill of lading. According to the different contents recorded in the "consignee" column, the bill of lading can be divided into a registered bill of lading, an instruction bill of lading and an anonymous bill of lading. Article 79 of China's Maritime Law stipulates three situations for the transfer of bills of lading: “The transfer of bills of lading shall be carried out in accordance with the following provisions: (1) The registered bill of lading shall not be transferred; (2) Instructing the bill of lading to be transferred by signed endorsement or blank endorsement; (3) An anonymous bill of lading can be transferred without endorsement.” The core function of the bill of lading is to replace maritime goods, and the transfer of the bill of lading transfers the rights commended by the bill of lading. According to the above regulations, bills of lading are divided into two types, negotiable and non-negotiable. Among them, registered bills of lading are not transferable, indicating that bills of lading and bearer bills of lading can be transferred. The process of transfer of bills of lading is usually achieved through endorsement transfer. The transfer of bill of lading is inseparable from two links: endorsement and delivery. Among them, the transfer of bills of lading is divided into two cases, endorsement plus delivery transfer and transfer without endorsement (ie delivery transfer). The meaning of delivery is clear, that is, the transfer of possession of the bill of lading. Instruct the bill of lading to endorse and deliver the transfer, and the bearer bill of lading to transfer the delivery, otherwise no legal effect will occur. The original meaning of the endorsement is "on the back", which is later extended to refer to the act of the holder of the document writing on the back of the document. There is no legal definition for the bill of lading endorsement, but its meaning generally means that the transferor of the bill of lading records and signs on the back of the bill of lading the instructions of who or by whom the goods are taken. Common endorsement transfers are mainly of the following types: 1. When the "consignee" is filled in the consignee column, it means that the shipper will endorse it. 2. When the consignee column fills in the instructions for registration, the designated person needs to endorse it. 3. When the harvester column is filled with the instructions of the shipper, as in the first case, the shipper will also endorse it.