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A formal option to renew a lease is a property right (technically it is an estate contract) enforceable by the Tenant against the Landlord. A question that sometimes arises is whether the option can be exercised against the new landlord, if the landlord who granted the option sells his Reversion to another person. Because the option to renew is only an equitable interest in the landlord's property, to be enforceable against the landlord's successor it must be registered. If the landlord's interest is unregistered, the option should be registered as a class C(iv) LandCharge; if registered, it should be noted against the landlord's title as a Notice.