Jus accrescendi
Ius accrescendi, in Roman law, is the right of survivorship, the right of the survivor or survivors of two or more joint tenants to the tenancy or estate, upon the death of one or more of the joint tenants.
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Wikipedia
Ius accrescendi, in Roman law, is the right of survivorship, the right of the survivor or survivors of two or more joint tenants to the tenancy or estate, upon the death of one or more of the joint tenants.