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The Rule Against Perpetuities

Property

The rule against perpetuities stops a grantor controlling land for generations through contingent future interests. In its classic form, an interest is void unless it must vest, if it vests at all, no later than twenty one years after the death of someone alive when the interest was created. The rule is about certainty rather than probability. If there is any possible sequence of events in which the interest vests too late, it fails from the outset.

Rule

Leading cases

Where students go wrong

The first mistake is asking what is likely. The common law rule asks what is possible, so an outcome with a vanishingly small chance still destroys the interest.

The second is applying the rule to interests it does not reach. Check the classification first, because a reversion or a fully vested remainder is never at risk.

The third is ignoring the reforms. Most states no longer apply the rule in its unforgiving form, so a complete answer states the common law result and then applies the local statute.

FAQ

Why twenty one years?
It approximated the time from a child's birth to the age of majority, so a grantor could provide for people alive at the time plus their children reaching adulthood, and no further.

What is a validating life?
A person alive when the interest was created whose life you can use to prove the interest must vest or fail within the period. Finding one saves the gift; being unable to find any means it fails.

Does the rule still matter?
Yes, though less than it did. Many states have softened or abolished it, but it still appears on exams and on the bar, and it still catches commercial options in some jurisdictions.

Related terms

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