law: Sale of Goods Act, 1930
  45. "Unpaid seller" defined
  (1) The seller of goods is deemed to be an "unpaid
  
  seller" within the meaning of this Act.-
  (a) When the whole of the price has not been
  
  paid or tendered;
  (b) When a bill of exchange or other
  
  negotiable instrument has been received as conditional payment, and the condition
  
  on which it was received has not been fulfilled by reason of the dishonor of
  
  the instrument or otherwise.
  (2) In this Chapter, the term "seller" includes any
  
  person who is in the position of a seller, as, for instance, an agent of the
  
  seller to whom the bill of lading has been endorsed, or a consignor or agent
  
  who has himself paid, or is directly responsible for, the price.