Rule in Dumpor's Case

The Rule in Dumpor's Case is a common law rule of property law first set forth by Sir Edward Coke in 1578 (4 Coke 1196 [1578]). In its most basic form, it states that once a landlord has consented to an assignment of a tenant's interest in a leasehold estate, he implicitly consents to all future assignments by the tenant.

This rule is still operative in some U.S. states and some other jurisdictions which follow English common law, but the parties may contract around the rule by putting a clause in the lease agreement which allows the landlord to reserve his right to approve or disapprove an assignment.

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