law: Transfer of Property Act, 1882
  60. Right of mortgagor to redeem
  At any time after the principal money has become due, the
  
  mortgagor has a right, on payment or tender, at a proper time and place, of the
  
  mortgage-money, to require the mortgagee (a) to deliver to the mortgagor the
  
  mortgage-deed and all documents relating to the mortgaged property which are in
  
  the possession or power of the mortgagee, (b) where the mortgagee is in
  
  possession of the mortgaged property, to deliver possession thereof to the
  
  mortgagor, and (c) at the cost of the mortgagor either to re-transfer the
  
  mortgaged property to him or to such third person as he may direct, or to
  
  execute and (where the mortgage has been effected by a registered instrument)
  
  to have registered an acknowledgement in writing that any right in derogation
  
  of his interest transferred to the mortgagee has been extinguished:
  PROVIDED that the right conferred by this section has
  
  not been extinguished by the act of the parties or by decree of a court.
  The right conferred by this section is called a right to redeem
  
  and a suit to enforce it is called a suit for redemption.
  Nothing in this section shall be deemed to render invalid any
  
  provision to the effect that, if the time fixed for payment of the principal
  
  money has been allowed to pass or no such time has been fixed, the mortgagee
  
  shall be entitled to reasonable notice before payment or tender of such money.
  Redemption of portion of mortgaged  property  -Nothing in this
  
  section shall entitle a person interested in a share only of the mortgaged
  
  property to redeem his own share only, on payment of a proportionate part of
  
  the amount remaining due on the mortgage, except only where a mortgagee, or, if
  
  there are more mortgagees than one, all such mortgagees, has or have acquired,
  
  in whole or in part, the share of a mortgagor.