Doctrine of merger
Introduction : --
      The doctrine of meager has been explained in S.101 under the chapter of charges and also u/s.111 (d) in respect of determination lease.

Doctrine of meager : --                                           
A) Mortgage and charge --
            Extinctions of mortgage security. A security may be extinguished by merger. This occur --
                 1) by the merger of a lower in a higher security; and
                2) by the merger of a lesser in a greater estate.
         A merger of estates takes place when two estates held in the same legal right becomes united in the same person.
  B) lease S. 111 (d) --
           When a lease hold and a reversion coincide, there is a merger of lesser estate in the greater. The lease hold is lesser estate, for it is carved out of the estate of owner, is the reversion. The lesser estate is merged, i.e. sunk or drowned in the greater. Thus if the lessor purchases the lessee's interest, the lease is extinguished as the same man cannot be at the same time both landlord and tenants . 
      when a landlord executes a sale deed in favour of the tenant there is a merger of interest and the tenancy comes to an end. There can be no merger of lease and mortgage, even where the two transactions are in respect of the same property. 


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