law: Transfer of Property Act, 1882
  42. Transfer by person having authority to revoke former
  
  transfer
  Where a person transfers any immovable property, reserving power
  
  to revoke the transfer, and subsequently transfers the property for
  
  consideration to another transferee, such transfer operates in favor of such
  
  transferee (subject to any condition attached to the exercise of the power) as
  
  a revocation of the former transfer to the extent of the power.
  Illustration
  A lets a house to B, and reserves power to revoke the lease if,
  
  in the opinion of a specified surveyor, B should make a use of it detrimental
  
  to its value. Afterwards A, thinking that such a use has been made, lets the
  
  house to C. This operates as a revocation of B's lease subject to the opinion
  
  of the surveyor as to B's use of the house having been detrimental to its
  
  value.