What is a bill of lading (B/L)?
The carrier or its agent issues the bill of lading once the cargo is received for shipment or, more commonly, loaded on board. It is usually issued as a set of originals, often three, and names the shipper, consignee, notify party, ports of loading and discharge, vessel, container numbers and a cargo description. Whoever presents an original at destination can claim the goods, which is why banks rely on it in letter-of-credit trades.
A negotiable B/L made out “to order” can be endorsed and handed on, so the cargo can be sold while it is still at sea. A straight B/L names a fixed consignee and cannot be transferred by endorsement, and a sea waybill is not a document of title at all. In forwarding, the carrier's document is the master bill of lading, while the forwarder or NVOCC issues its own house bill of lading to the actual shipper.
Most problems come from details: a misspelled consignee, a weight that differs from the invoice or VGM, or a remark about damaged packaging that makes the bill “claused”, which a bank can refuse under a letter of credit. Forwarders check the draft B/L against the booking and credit terms before originals are issued, since later amendments cost time and usually a fee. A lost original can stall release until the carrier accepts a letter of indemnity, often bank-countersigned.