Also known as: unity of time · unity of title · unity of interest · unity of possession · four unities · joint tenancy unities
Written by attorneys · grounded in primary & secondary sources — see below
The four common-law requirements that must concur for a joint tenancy to arise. Each co-owner must acquire title at the same moment, from the same instrument, with identical fractional shares, and with an equal right to possess the whole property.
Ulysses Ulrich and Usman Uddin receive a single deed conveying Blackacre to them simultaneously as joint tenants with right of survivorship. Because the deed satisfies the four unities, each holds an undivided half interest that passes automatically to the survivor upon the other's death.
Uma Upadhyay conveys her interest in Greenacre to Ulric Unger by separate deed one week after Ulrike Ulrich already holds title. The staggered conveyances break the unity of time, so the parties hold only as tenants in common rather than joint tenants.
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The estate becomes a tenancy in common. The four unities must all exist at the moment of creation. Absence of any one prevents joint tenancy and its right of survivorship.
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Tenancy by the entirety requires the four unities plus unity of person because the spouses are treated as one legal entity. This extra unity prevents one spouse from unilaterally severing the tenancy.
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Yes, when local law still requires the four unities. The undivided shares must be identical, so A and each child of B take equal fractional interests rather than A taking one-half outright.
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…or as appellants, and Hupp and those associated with him will be referred to as Hupp or as the appellees, for there is a unity of interest among the parties on the two sides of the case, respectively. 1. The prime problem is to determine the quality of the appellees’ acts in entering upon the property and extracting the oil.…