In the law of real property, the merger doctrine stands for the proposition that the contract for the conveyance of property merges into the deed of conveyance; therefore, any guarantees made in the contract that are not reflected in the deed are extinguished when the deed is conveyed to the buyer of the property.
The merger doctrine traditionally applies only to covenants of title; covenants relating to the physical condition of the property (say, a promise that the furnace is in good working order) will not merge, and will not extinguish.
[citation needed] The merger also refers to the doctrine whereby "a fee simple estate, once fragmented into present and future interests, can thereafter be reconstituted.
"[1] Similarly, a merger doctrine extinguishes an easement by necessity to a landlocked piece of property once that property is sold to one of the adjoining owners, thus extinguishing the necessity.
[2] Although municipalities may themselves misinterpret the rules by which merger occurs, various conditions – spatial arrangement, past development, ownership, and nonconformity – must be met for an actual merger to occur.