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A form of Mortgage where the mortgagee acquires a long Lease over the Freehold estate that is mortgaged. The lease gives the mortgagee a right of possession, which allows him to enforce his rights over the estate in the event of default by the Mortgagor.

Where land is registered, there is no need to create a mortgage by demise: a mortgage by way oflegal charge is administratively simpler and carries the same rights. Consequently mortgages by demise are obsolete and, under the Lra (2002), may not longer be created against registered land.