The Rule Against Perpetuities

The Rule Against Perpetuities

1. Introduction

Few doctrines in property law have a reputation as intimidating as the Rule Against Perpetuities.

Law students often encounter it as a collection of strange conveyances involving unborn children, grandchildren, and conditions that might happen decades in the future. The traditional rule is highly technical, and its language can initially seem disconnected from ordinary property law.

But the underlying idea is relatively simple.

The Rule Against Perpetuities is concerned with how long a property owner can control the ownership of property after the owner’s own interest has ended.

Property law generally permits owners to decide who will receive their property in the future. But the law has historically placed limits on the ability to control property indefinitely.

The traditional rule is commonly stated as follows:

No interest is good unless it must vest, if at all, not later than 21 years after some life in being at the creation of the interest.

The language is difficult.

The underlying concern is easier:

The law generally does not want certain future interests to remain uncertain for an excessively long period of time.

The Rule Against Perpetuities therefore represents a balance between two competing policies:

• respecting an owner’s freedom to arrange the future ownership of property; and
• preventing property from being controlled indefinitely by people who are no longer alive.

Modern property law has substantially modified the traditional rule in many jurisdictions. Some states have adopted statutory reforms, extended perpetuities periods, adopted “wait and see” approaches, or abolished the rule for certain interests.

Nevertheless, the traditional rule remains an important part of property-law education because it provides the foundation for understanding modern perpetuities doctrine.

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2. What Does “Perpetuity” Mean?

A perpetuity is something that continues indefinitely.

In property law, the concern is not that land itself might exist forever.

A fee simple absolute can potentially last forever.

The concern is that an owner might attempt to impose restrictions or create future interests that control the property indefinitely.

For example, imagine:

“I give Blackacre to my son, but after his death it shall pass to whichever of his descendants my great-great-grandchildren choose.”

Such arrangements can create uncertainty about who ultimately owns the property.

The law has historically been concerned that property should remain alienable and transferable, rather than being locked into a chain of remote future interests.

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3. The Policy Behind the Rule

The Rule Against Perpetuities is based on several related policies.

Freedom of alienation

Property should generally be capable of being sold, transferred, mortgaged, and otherwise dealt with.

Marketability of title

Buyers and lenders need to know who has legally enforceable interests in property.

Productive use

Property should not be burdened by restrictions that prevent future owners from using it effectively.

Intergenerational freedom

People who are alive today should not be able to control property indefinitely after their deaths.

Limiting dead-hand control

The doctrine limits the ability of a deceased property owner to dictate the property’s ownership far into the future.

The Rule Against Perpetuities is therefore part of a broader principle:

Property law generally favors present and future owners having meaningful freedom to control their property.

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4. The Traditional Rule

The traditional common-law formulation is:

No interest is good unless it must vest, if at all, not later than 21 years after the death of a life in being at the creation of the interest.

Every part of this sentence matters.

The rule concerns:

• a particular type of future interest;
• whether that interest will vest;
• whether it must vest within a specified period;
• and whether the relevant period is measured by a life in being plus 21 years.

The difficulty comes from understanding exactly what these concepts mean.

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5. What Does “Vest” Mean?

In this context, vesting generally means that the future interest becomes sufficiently fixed in the holder.

This does not necessarily mean that the person has possession.

For example:

“To Alice for life, then to Bob.”

Bob has a vested remainder.

Bob does not possess the property until Alice dies, but his interest is already vested.

The Rule Against Perpetuities therefore focuses on vesting, not simply possession.

This distinction is critical.

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6. Vesting Is Not the Same as Possession

Consider:

“To Alice for life, then to Bob.”

Alice has possession.

Bob has a future interest.

Bob’s interest is vested even though he cannot yet possess the property.

Therefore:

Present possession ≠ vesting

and:

Future possession ≠ lack of vesting

The perpetuities analysis asks when the legal interest becomes sufficiently certain, not merely when the person gets physical possession.

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7. Which Interests Are Traditionally Subject to the Rule?

The traditional Rule Against Perpetuities applies primarily to certain unvested future interests.

The classic categories include:

• contingent remainders;
• executory interests;
• vested remainders subject to open.

It generally does not apply to:

• indefeasibly vested remainders;
• reversions;
• possibilities of reverter;
• rights of entry.

The precise application can be affected by modern statutes.

Therefore, the first step in any perpetuities analysis is:

Identify the future interest.

Do not begin applying the Rule Against Perpetuities before determining what kind of interest exists.

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8. Contingent Remainders

Contingent remainders are particularly important under the traditional rule.

Consider:

“To Alice for life, then to Bob if Bob survives Alice.”

Bob’s interest depends upon a condition precedent.

Bob must survive Alice before the remainder can become possessory.

Because the interest is contingent, the Rule Against Perpetuities may apply.

Now compare:

“To Alice for life, then to Bob.”

Bob has an indefeasibly vested remainder.

The traditional Rule Against Perpetuities generally does not invalidate Bob’s interest.

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9. Executory Interests

Executory interests are another major category.

Consider:

“To Alice, but if the property is ever used as a nightclub, then to Bob.”

Bob has an executory interest.

The interest could potentially divest Alice at some future time.

Because executory interests can remain uncertain for a remote period, they are traditionally subject to the Rule Against Perpetuities.

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10. Vested Remainders Subject to Open

A class gift can also create perpetuities problems.

Consider:

“To Alice for life, then to Alice’s children.”

If Alice already has children, their interests may be vested subject to open because additional children could be born.

The law must therefore consider when the class can finally close and whether any member could obtain an interest too remotely.

This is one reason class gifts are particularly important in perpetuities analysis.

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11. The “Life in Being”

The traditional rule uses the concept of a life in being.

A life in being is a person who is alive at the time the future interest is created and whose life can be used as the measuring life for determining when the interest must vest.

For example:

“To Alice for life, then to Bob.”

Alice may be a relevant life in being.

If the interest must become fixed no later than 21 years after Alice’s death, the traditional perpetuities period can be satisfied.

The key is not simply whether Alice is alive.

The question is whether Alice’s life is logically connected to the vesting of the future interest.

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12. The “21 Years” Component

Why 21 years?

Historically, 21 years corresponds roughly to the age at which a person was traditionally regarded as reaching legal adulthood.

The rule therefore permits uncertainty to continue beyond the life of the relevant measuring person for a limited additional period.

The traditional structure is:

Life in being + 21 years

The future interest must vest, if at all, within that period.

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13. The Important Word: “Must”

The traditional Rule Against Perpetuities asks whether the interest must vest within the permitted period.

This is where the doctrine becomes particularly difficult.

The question is not:

“Will the interest probably vest within the period?”

It is:

“Is there any possible scenario in which the interest could vest too remotely?”

If such a possibility exists under the traditional common-law analysis, the interest can be invalid from the moment it is created.

This is sometimes called the possibility of remote vesting.

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14. The “Worst-Case Scenario” Approach

Traditional perpetuities analysis requires lawyers to imagine the most remote legally possible scenario.

Consider:

“To Alice for life, then to Alice’s first child to reach age 30.”

Suppose Alice has a child who is one year old.

It may seem likely that the child will reach 30 relatively soon.

But the traditional rule does not ask what is likely.

It asks whether the interest could vest too remotely.

The analysis therefore considers legally possible scenarios rather than statistical probabilities.

This is why the Rule Against Perpetuities can produce results that seem counterintuitive.

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15. A Classic Example

Consider:

“To A for life, then to A’s first child to reach 25.”

At first glance, this might seem harmless.

Suppose A has a child who is two years old.

The child could reach 25 during A’s lifetime.

But suppose A has another child shortly before A dies.

That child might not reach age 25 until more than 21 years after A’s death.

Under the traditional rule, that possibility can create a problem.

The interest therefore may be invalid even though the event will probably occur much earlier.

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16. Another Classic Example

Consider:

“To A for life, then to A’s first grandchild to reach 25.”

This raises even greater concerns.

A could have a child after the conveyance.

That child could have a child after A’s death.

The grandchild could then reach 25 more than 21 years after A’s death.

The traditional rule examines whether that possibility exists.

If the interest could vest too remotely, the interest is invalid under the traditional common-law rule.

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17. The Rule Is Not About When Possession Begins

This is one of the most important points.

Suppose:

“To Alice for life, then to Bob.”

Bob may not possess the property for many years.

That does not create a Rule Against Perpetuities problem because Bob’s remainder is already vested.

The rule concerns the time when the interest vests, not necessarily when possession begins.

Thus:

Long wait for possession ≠ perpetuities violation

if the future interest is already vested.

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18. The “Bad” Interest Can Be Void From the Beginning

Under traditional common law, if an interest violates the Rule Against Perpetuities, it is generally void from the moment the interest is created.

The court does not wait decades to see what actually happens.

This is another reason the traditional doctrine is so severe.

Suppose an interest could theoretically vest too remotely.

Even if events later unfold in a way that would have satisfied the rule, the interest was traditionally invalid from the outset.

Modern reforms have softened this result in many jurisdictions.

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19. The Rule Applies to Possibilities, Not Probabilities

This is perhaps the most important exam principle.

Under traditional doctrine:

Possibility, not probability.

Suppose a future interest has a 99.9% chance of vesting within the perpetuities period.

If there is a legally possible scenario in which it could vest too late, the interest may violate the traditional rule.

The doctrine therefore requires careful hypothetical reasoning.

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20. “Wait and See”

Because the traditional rule can produce harsh results, some jurisdictions adopted the wait-and-see approach.

Under this approach, instead of immediately invalidating an interest based solely on a possibility of remote vesting, courts may wait to see what actually happens.

If the interest ultimately vests within the permissible period, it can be upheld.

If it becomes clear that the interest cannot vest within the required period, it can be invalidated.

This approach reduces the harshness of the traditional rule.

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21. The Uniform Statutory Rule Against Perpetuities

Many jurisdictions have adopted statutory reforms based in part on the Uniform Statutory Rule Against Perpetuities.

These statutes can substantially modify traditional common-law doctrine.

One common modern approach provides a statutory perpetuities period that can extend well beyond the traditional:

life in being + 21 years.

The exact period and available exceptions depend on the jurisdiction.

Some states have adopted the uniform approach with modifications.

Others have adopted different reforms.

Some have abolished the rule entirely for certain property interests.

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22. Modern Perpetuities Law Is Not Uniform

There is no single modern Rule Against Perpetuities that operates identically throughout the United States.

State law may:

• retain the traditional common-law rule;
• modify the rule;
• adopt a wait-and-see approach;
• provide an extended statutory period;
• allow judicial reformation;
• exempt certain trusts;
• abolish the rule for certain interests.

This is especially important in actual legal practice.

A lawyer should never assume that the traditional common-law rule is automatically the governing law.

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23. The Rule and Trusts

Perpetuities law is particularly important in the context of trusts.

A trust may attempt to control property for generations.

For example:

“Income shall be paid to my descendants for as long as any descendant of mine is alive, and the property shall then pass to…”

Such provisions can raise perpetuities questions.

Modern trust law in some jurisdictions permits extremely long-lasting or even perpetual trusts under specified conditions.

Other jurisdictions continue to impose substantial limitations.

Therefore, the relationship between the Rule Against Perpetuities and trusts is highly jurisdiction-specific.

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24. The Rule and Estate Planning

Estate planners must consider perpetuities rules when drafting provisions that control property after death.

Potentially relevant arrangements include:

• generation-skipping gifts;
• trusts for descendants;
• contingent gifts;
• class gifts;
• powers of appointment;
• long-term property restrictions.

A provision that seems sensible from an estate-planning perspective may create a perpetuities problem if it leaves the ultimate ownership uncertain for too long.

Modern statutes have made sophisticated estate planning considerably more flexible in many jurisdictions.

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25. The Rule and Class Gifts

Class gifts are especially important because membership can change.

Consider:

“To Alice for life, then to Alice’s grandchildren.”

The question becomes:

• When does the class close?
• Who can become a member?
• Can a future-born person qualify?
• Can that person’s interest vest too remotely?

The rule of convenience can sometimes help determine when a class closes, but it must be considered together with other doctrines.

Class gifts therefore require careful analysis under both remainder doctrine and perpetuities law.

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26. The Rule of Convenience

The rule of convenience is a traditional doctrine concerning class gifts.

In general terms, a class may close when a member of the class becomes entitled to distribution or possession, unless the instrument or applicable law provides otherwise.

For example:

“To Alice for life, then to Alice’s children.”

When the time comes for the children to take possession, the class may close under the applicable rule.

However, the rule contains important qualifications and exceptions.

Modern statutes may also modify traditional class-closing principles.

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27. The Rule Against Perpetuities and Vested Remainders

It is important not to assume that every remainder is vulnerable to the Rule Against Perpetuities.

Consider:

“To Alice for life, then to Bob.”

Bob has an indefeasibly vested remainder.

There is no uncertainty about who holds the remainder.

The only uncertainty is when Bob gets possession.

That is not ordinarily a perpetuities problem.

Now compare:

“To Alice for life, then to Bob if Bob reaches age 30.”

Bob’s interest is contingent.

Now the Rule Against Perpetuities may become relevant.

The distinction between vested and contingent interests is therefore fundamental.

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28. The Rule Against Perpetuities and Reversions

A reversion is traditionally not subject to the Rule Against Perpetuities.

Suppose:

“To Alice for life.”

O retains a reversion.

The reversion does not become invalid simply because Alice might live for many decades.

Why?

Because O’s reversion is already vested in O.

There is no uncertainty about who owns the future interest.

The only question is when possession will return.

Again:

Uncertain possession is not the same thing as uncertain vesting.

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29. The Rule Against Perpetuities and Possibility of Reverter

A possibility of reverter is traditionally treated differently from a contingent remainder or executory interest.

Suppose:

“To Alice so long as the property is used as a school.”

O retains a possibility of reverter.

Traditionally, the possibility of reverter is not subject to the Rule Against Perpetuities in the same way as an executory interest.

Modern law may impose other statutory limitations.

The important conceptual distinction is that the transferor’s retained interest is already fixed in the transferor.

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30. The Rule Against Perpetuities and Executory Interests

Executory interests are classic subjects of perpetuities analysis.

Consider:

“To Alice, but if the property is ever used as a nightclub, then to Bob.”

Suppose the condition might occur centuries in the future.

Bob’s executory interest remains capable of cutting short Alice’s estate.

Under traditional law, that possibility can trigger the Rule Against Perpetuities.

This illustrates the policy concern: Bob’s interest could potentially control the property long after the original parties have died.

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31. A Practical Perpetuities Analysis

When faced with a Rule Against Perpetuities problem, use a systematic process.

Step 1: Identify the future interest

Determine whether it is:

• contingent remainder;
• executory interest;
• vested remainder subject to open;
• or another interest potentially covered by the rule.

Step 2: Identify when the interest is created

The relevant time is generally when the instrument becomes effective.

For a will, that is generally the testator’s death.

For an inter vivos conveyance, it is generally when the conveyance becomes effective.

Step 3: Identify the relevant measuring lives

Look for people whose lives are logically connected to the vesting of the interest.

Step 4: Ask whether the interest must vest within the permissible period

Do not ask what is probable.

Ask what is legally possible.

Step 5: Search for a remote-vesting possibility

Construct the worst legally possible scenario.

Step 6: Determine whether the jurisdiction modifies the common-law rule

Check for:

• wait-and-see;
• statutory perpetuities periods;
• reformation;
• special exceptions;
• abolition.

Step 7: Determine the consequence

If the traditional rule applies and the interest is invalid, determine what interest remains after removing the invalid provision.

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32. The “Measuring Life” Method

A useful way to simplify traditional perpetuities problems is to search for a measuring life.

Suppose:

“To Alice for life, then to Alice’s first child to reach 25.”

Ask:

Is Alice a measuring life?

If the child’s interest must necessarily become fixed during Alice’s life or within 21 years after Alice’s death, the rule may be satisfied.

But if a child could be born shortly before Alice dies and reach 25 more than 21 years later, the traditional rule may be violated.

The key is whether the measuring life actually controls the vesting event.

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33. The “Unborn Widow” Problem

Traditional perpetuities doctrine sometimes produces particularly strange hypothetical problems.

One example involves an “unborn widow.”

Suppose property is given to a person’s descendants subject to conditions involving the descendants’ spouses.

A person who is not yet born could theoretically become the relevant spouse or beneficiary.

Because that person is not a life in being when the interest is created, the traditional rule can create an unexpectedly long period of uncertainty.

These hypothetical constructions illustrate why the doctrine became famous for its technical complexity.

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34. The “Slothful Executor” and Other Hypotheticals

Property-law courses often use deliberately extreme hypotheticals to test the Rule Against Perpetuities.

The point is not to predict realistic events.

The point is to determine whether a legally possible chain of events could delay vesting beyond the permissible period.

These hypotheticals can seem absurd because the doctrine itself requires lawyers to consider remote possibilities.

The lesson is:

Traditional perpetuities analysis is a logical test, not a probability test.

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35. Why the Traditional Rule Can Seem Unfair

Suppose a property owner creates a provision that, in actual life, would resolve within ten years.

But a highly remote hypothetical could cause vesting more than 21 years after the death of every relevant measuring life.

Under the traditional rule, the interest could be invalid.

This means:

• the actual outcome may be perfectly reasonable;
• the drafting may have been intended to be reasonable;
• yet the interest can still fail.

This rigidity is one reason modern jurisdictions have adopted reforms.

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36. Reformation

Some modern statutes permit courts to reform an offending provision.

Instead of simply declaring the interest invalid, a court may modify the provision to bring it within the permissible perpetuities period while preserving the transferor’s general intent as far as possible.

This approach recognizes that automatic invalidation can defeat legitimate estate-planning objectives.

Again, the availability and method of reformation depend on state law.

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37. The Rule and Charitable Transfers

Charitable gifts have historically received special treatment under certain perpetuities doctrines.

For example, a transfer from one charity to another charity may receive different treatment from a private transfer.

Charitable trusts can also be subject to specialized rules.

However, the exact exceptions and statutory treatment vary by jurisdiction.

A lawyer dealing with a charitable trust should therefore examine the governing statute rather than assume that traditional common-law rules provide the complete answer.

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38. Perpetuities and Marketability of Title

The Rule Against Perpetuities is closely connected to title.

Suppose a deed creates a remote executory interest in a future beneficiary.

A buyer may be uncertain whether that beneficiary could someday claim the property.

This uncertainty can complicate:

• title insurance;
• financing;
• sales;
• development;
• estate planning;
• litigation.

Perpetuities doctrine therefore serves a practical function beyond abstract legal theory.

It helps prevent property from becoming burdened with unresolved future claims.

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39. Perpetuities and Freedom of Alienation

The doctrine also relates to the broader policy favoring alienability.

Alienability means the ability to transfer property freely.

If an owner could impose unlimited future conditions, property could become difficult to sell or finance.

For example:

“The property may never be sold outside my descendants.”

A restriction of this kind may raise separate questions concerning restraints on alienation, even apart from the Rule Against Perpetuities.

The two doctrines are related but not identical.

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40. Rule Against Perpetuities vs. Restraints on Alienation

These doctrines should not be confused.

Rule Against Perpetuities

Primarily concerns certain future interests that may vest too remotely.

Restraints on alienation

Concern restrictions on the ability to transfer property.

A provision can potentially implicate:

• perpetuities doctrine;
• restraint-on-alienation doctrine;
• public policy;
• statutory rules.

A lawyer should analyze each doctrine separately.

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41. Rule Against Perpetuities vs. Duration of Ownership

The Rule Against Perpetuities does not mean that property cannot be owned forever.

Fee simple absolute can continue indefinitely.

A person can also potentially hold property for life.

The doctrine is concerned with certain future interests and their vesting, not with the mere duration of ownership.

This distinction prevents one of the most common misunderstandings about the rule.

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42. Modern Property Law

The Rule Against Perpetuities illustrates a broader characteristic of U.S. property law:

Historical common law remains important, but modern statutes often modify it substantially.

A law student should therefore understand two layers.

First: traditional doctrine

Learn:

• the traditional rule;
• measuring lives;
• 21 years;
• vesting;
• contingent remainders;
• executory interests;
• vested remainders subject to open;
• possibility of remote vesting.

Second: modern law

Determine:

• the applicable state statute;
• statutory perpetuities periods;
• wait-and-see rules;
• reformation;
• exceptions;
• special trust rules.

This two-step approach avoids applying historical doctrine mechanically to modern transactions.

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43. Common Mistakes

Mistake 1: Thinking the rule prohibits perpetual ownership

It does not.

Mistake 2: Focusing on possession rather than vesting

The rule concerns vesting, not simply when someone receives possession.

Mistake 3: Asking what is likely to happen

Traditional doctrine asks what is legally possible.

Mistake 4: Applying the rule to every future interest

Some future interests are traditionally outside the rule.

Mistake 5: Forgetting vested remainders

An indefeasibly vested remainder generally does not create the same perpetuities problem as a contingent remainder.

Mistake 6: Ignoring class gifts

Class gifts can remain open and create complex vesting questions.

Mistake 7: Assuming the common-law rule is always current

Modern state statutes can substantially modify or abolish the traditional rule.

Mistake 8: Ignoring the jurisdiction

Perpetuities law is highly jurisdiction-specific.

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44. A Simplified Mental Model

For beginners, think about the Rule Against Perpetuities as a question of uncertainty over time.

Ask:

Is the law being asked to tolerate uncertainty about who will ultimately receive the property for too long?

If the future interest is already fixed in a person, there may be no perpetuities problem.

If the identity of the future owner or the existence of the interest depends on an uncertain event that could occur far in the future, the rule may become relevant.

This is not a substitute for the formal doctrine, but it provides a useful conceptual starting point.

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45. Key Takeaways

• The Rule Against Perpetuities limits certain future interests that may vest too remotely.
• The traditional rule is commonly expressed as: an interest must vest, if at all, within a life in being plus 21 years.
• The traditional rule focuses on vesting, not merely possession.
• It asks about possibility, not probability.
• A future interest can be invalid from the moment it is created under traditional common law.
• Contingent remainders, executory interests, and vested remainders subject to open are classic interests subject to the rule.
• Reversions, possibilities of reverter, and indefeasibly vested remainders are traditionally outside the rule.
• Class gifts can create difficult perpetuities questions.
• The rule is closely related to policies favoring alienability, marketability, and freedom from excessive dead-hand control.
• Modern jurisdictions have substantially modified the traditional rule.
• Modern approaches may include wait-and-see rules, extended statutory periods, judicial reformation, and exemptions.
• The governing jurisdiction must always be identified before applying the rule to an actual transaction.

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46. Frequently Asked Questions

What is the Rule Against Perpetuities?

It is a property-law doctrine limiting certain future interests that might vest too remotely.

What is the traditional Rule Against Perpetuities?

The traditional rule provides that a future interest is invalid unless it must vest, if at all, no later than 21 years after the death of a relevant life in being when the interest was created.

What does “vest” mean?

In this context, vesting generally means that the future interest becomes sufficiently fixed in its holder. Vesting is different from possession.

Does the rule prohibit perpetual ownership?

No. A fee simple absolute can potentially last forever. The rule concerns certain future interests, not perpetual ownership itself.

Does the rule apply to every future interest?

No. Traditionally, it primarily applies to contingent remainders, executory interests, and vested remainders subject to open.

Why is the rule based on possibility rather than probability?

Traditional common law seeks to determine whether an interest could possibly vest too remotely, rather than whether remote vesting is likely.

What is a life in being?

A life in being is generally a person alive when the interest is created whose life can serve as the relevant measuring life for the perpetuities period.

Why 21 years?

The traditional period allows uncertainty to continue for 21 years beyond the death of a relevant measuring life, reflecting historical legal concepts concerning adulthood and inheritance.

Can a perpetuities problem arise with a trust?

Yes. Trusts can create future interests that raise perpetuities questions, although modern trust statutes vary substantially.

Is the traditional Rule Against Perpetuities still the law?

Not everywhere. Many jurisdictions have modified the rule substantially, while some have abolished it for particular interests or circumstances.

Why should lawyers still learn the traditional rule?

Because it remains the foundation for understanding modern perpetuities doctrine and is still important in legal education, historical property law, and jurisdictions that retain elements of the traditional approach.

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47. Further Reference

For general background on property law and related legal concepts, see:

Cornell Law School – Wex: Property

Cornell Law School – Wex: Real Property

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Conclusion

The Rule Against Perpetuities is often presented as one of the most difficult doctrines in property law. Its traditional formulation certainly deserves that reputation.

But its central purpose is easier to understand.

Property law allows owners to plan for the future. An owner can create life estates, remainders, trusts, and other arrangements that determine who will receive property later. But the law has historically refused to allow certain forms of uncertainty over ownership to continue indefinitely.

The traditional rule therefore asks whether a particular future interest must vest within a legally permitted period.

The most important ideas are these:

Vesting matters, not merely possession.

Possibility matters, not probability.

Certain future interests are covered, while others are traditionally excluded.

And, perhaps most importantly for modern practice:

The jurisdiction matters.

The traditional common-law Rule Against Perpetuities remains foundational, but modern statutes have substantially changed the doctrine in many states. A lawyer must therefore understand the historical rule well enough to identify the issue, and then determine what the governing jurisdiction actually provides.

At its deepest level, the Rule Against Perpetuities reflects a fundamental tension in property law:

How much control should one generation be allowed to exercise over property that will belong to generations yet unborn?

The answer has never been simply “none.” Nor has it been “forever.”

The Rule Against Perpetuities represents the law’s attempt to draw the line between legitimate planning and excessive control over the distant future.