1911 Encyclopædia Britannica/Coparcenary
COPARCENARY (co-, with, and parcener, i.e. sharer; from O. Fr. parçonier, Lat. partitio, division), in law, the descent of lands of inheritance from an ancestor to two or more persons possessing an equal title to them. It arises either by common law, as where an ancestor dies intestate, leaving two or more females as his co-heiresses, who then take as coparceners or parceners; or, by particular custom, as in the case of gavelkind lands, which descend to all males in equal degrees, or in default of males, to all the daughters equally. These co-heirs, or parceners, have been so called, says Littleton (§ 241), “because by writ the law will constrain them, that partition shall be made among them.” Coparcenary so far resembles joint tenancy in that there is unity of title, interest and possession, but whereas joint tenants always claim by purchase, parceners claim by descent, and although there is unity of interest there is no entirety, for there is no jus accrescendi or survivorship. Coparcenary may be dissolved (a) by partition; (b) by alienation by one coparcener; (c) by all the estate at last descending to one coparcener, who thenceforth holds in severalty; (d) by a compulsory partition or sale under the Partition Acts.
The term “coparcenary” is not in use in the United States, joint heirship being considered as tenancy in common.