law: Transfer of Property Act, 1882
  40. Burden of obligation imposing restriction on use of
  
  land
  Where, for the more beneficial enjoyment of his own immovable
  
  property, a third person has, independently of any interest in the immovable
  
  property of another or of any easement thereon, a right to restrain the
  
  enjoyment in a particular manner of the latter property, or
  Or of obligation annexed to ownership but not amounting to
  
  interest or easement : Where a third person is entitled to the benefit of an
  
  obligation arising out of contract and annexed to the ownership of immovable
  
  property, but not amounting to an interest therein or easement thereon,
  such right or obligation may be enforced against a transferee
  
  with notice thereof or a gratuitous transferee of the property affected
  
  thereby, but not against a transferee for consideration and without notice of
  
  the right or obligation, nor against such property in his hands.
  Illustration
  A contracts to sell Sultanpur to B. While the contract is still
  
  in force he sells Sultanpur to C, who has notice of the contract. B may enforce
  
  the contract against C to the same extent as against A.