The unpaid seller of goods has, by law, two kinds of rights: (i) rights against the goods themselves and (ii) right against the buyer personally. The former are treated by secs. 45-54 of the Act; the latter by secs. 55 and 56 of the Act.
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Unpaid Seller: An unpaid seller is defined by sec. 45 as a seller (i) to whom the whole price has not been paid or tendered; (ii) where a bill of exchange or other negotiable instrument has been accepted by him as conditional payment, when the condition has not been fulfilled by reason of the dishonor of the instrument or otherwise (sec 45). Notice that seller here includes persons in the position of a seller also, e.g. the agent of the seller to whom the bill of lading has been endorsed an agent who has himself paid the price, and an agent who is personally liable for the price.