Rule Against Perpetuities

No interest in property is valid unless it must vest, if at all, within a life in being at the creation of the interest plus 21 years. Under the modern wait-and-see approach (adopted in many states and the Uniform Statutory Rule Against Perpetuities), an interest is valid if it actually vests within 90 years.

Related Present Estates & Future Interests rules

• Fee Simple AbsoluteA fee simple absolute is an estate of potentially infinite duration with no conditions or limitations. It is freely…
• Defeasible Fees — OverviewA defeasible fee is a fee simple that may be terminated upon the occurrence of a stated event. The three types are:…
• Fee Simple DeterminableA fee simple determinable automatically terminates and reverts to the grantor upon occurrence of a stated event.…
• Fee Simple Subject to Condition SubsequentA fee simple subject to condition subsequent does not automatically terminate upon breach; the grantor must exercise a…
• Fee Simple Subject to Executory LimitationA fee simple subject to executory limitation automatically terminates upon occurrence of a stated event and passes to…
• Life EstateA life estate is an estate measured by the life of the holder (life tenant) or another person (estate pur autre vie).…
• Remainders — Vested and ContingentA remainder is a future interest in a third party that becomes possessory upon natural expiration of the prior estate.…
• Executory InterestsAn executory interest is a future interest in a third party that cuts short a prior estate rather than following its…

Part of Real Property on Core Legal Rules — foundational MBE-tested principles with primary-source citations.