partial release (or the rule in Dumpor's Case)

1. A partial release of a condition attached to the grant of an estate or interest in land. Under common law, based on the rule in Dumpor's Case (1603) 4 Co Rep 119b, 76 Eng Rep 1110, any partial release of a condition was deemed a total release. Thus, if a landlord agreed to an assignment, which was otherwise prohibited without consent, any further assignment no longer required the consent of the landlord (although a 'defeasance clause' may be inserted to revive the restriction after each consent) (Chipman v. Emeric, 5 Cal 49, 63 Am Dec 80 (1885)). This rule was abolished in English law in 1859 and now any licence or consent given to a lessee is treated as a one-time consent that does not affect any such future consent (Law of Property Act 1925, s. 143(1)). Similarly, in the US, the rule is not upheld in most jurisdictions, especially in relation to subletting (Moss v. Chappell, 126 Ga 196, 54 S.E. 968 (1906); German-American Savings Bank v. Gollmer, 155 Cal 683, 102 P 932 (1909); Northerly Corp. v. Hermett Realty Corp., 15 AD.2d 888, 225 NYS.2d 327 (1962); 49 Am.Jur.2d., L & T (Rochester, NY), § 422; The American Law Institute, Restatement Second, Property (Landlord and Tenant) (St. Paul, MN: 1977), § 16.1, Comment g). Nonetheless, in a jurisdiction where the rule is still applicable, it may be averted if the landlord reserves the right to approve any future assignment or subletting when he grants each and every consent. See also partial release clause^(US).

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