•Unity of Interest: Each tenant must hold the same interest in the property at thesame time. Therefore, a joint tenancy cannot exist where A has a fee simple interestand B has a life estate over the same land.•Unity of Title: Each tenant must hold title over the same property through the sameinstrument. •Unity of Time: Each tenant must have received their proprietary interest at the sametime, otherwise a tenancy in common will arise. Creation of Co-Ownership•Thecommon law would presume the formation of a joint tenancy where possible(usually through express words), unless the four unities were not present, theexistence of words of severance, and an intention to create a tenancy in common. •Equity would presume the formation of a tenancy in common in the following:–Where co-owners contribute different amounts to the purchase price: Theformation of a resulting trust in Trustees of the Property of Cummins (a bankrupt) vCummins (2006) 227 CLR 278.–Where co-owners advance money on mortgage: The law presumes that the co-owner wishes to get back their own investment, Conveyancing Act 1919 (NSW), ss96A and 99.–Partnership assets: The law presumes that the co-owner wishes to get back theirown investment. This was the case in regards to a gift from the father to his wife andtheir son. When the couple separated, the son was found to have a tenancy incommon: Roda v Roda  FamCAFC 27.Conveyancing Act 1919 (NSW), s 26(1):•“In the construction of any instrument coming into operation after thecommencement of this Act a disposition of the beneficial interest in any propertywhether with or without the legal estate to or for two or more persons together
beneficially shall be deemed to be made to or for them as tenants in common, andnot as joint tenants.”•The statute assumes a tenancy in common rather than a joint tenancy, even ifexplicitly stated otherwise: Minter v Minter (2000) 10 BPR 18.•Legal and equitable interests are subject to s 26(1): Delehunt v Carmody (1986) 161CLR 464.•S 26(1) applies to Torrens title land, unless the parties are expressly found to be jointtenants under RPA, s 100(1): Hircock v Windsor Homes (Development No 3) Pty Ltd 1 NSWLR 501.Severance of Joint Tenancy•A joint tenant can dispose his or her interest inter vivos (i.e. to another livingperson). •According to Corin v Patton (1990) 169 CLR 540, per Deane J, the formula forcalculating the share of property after a severance is N−1N.•N is the total number of joint tenants prior to severance. Therefore, the effect ofseverance is to deprive the other tenants of their right to survivorship over thesevered party’s share of property.•A severance of joint tenancy can be effected in six ways:By unilateral act by a joint tenant acting on his or her own share: •This can be achieved in three ways.