A more thorough explanation:

A nonnegotiable document of title is a written description, identification, or declaration of goods that authorizes the holder, usually a bailee, to receive, hold, and dispose of the document and the goods it covers. Unlike a negotiable document of title, a nonnegotiable document of title merely serves as evidence of the goods it covers.

Examples of nonnegotiable documents of title include bills of lading, warehouse receipts, and delivery orders. These documents do not stand for the goods they cover, and any transfer of the goods requires a surrender of the document.

For instance, if a warehouse issues a nonnegotiable warehouse receipt to a customer who stores goods in the warehouse, the receipt serves as evidence of the goods' existence and ownership. The customer cannot transfer the goods to another person without surrendering the receipt to the warehouse.