The Rule Against Perpetuities and Its Reforms

Chapters 12 through 14 established that ownership may be divided across time, that the division is accomplished by future interests, and that those interests may be retained by the transferor or created in transferees, vested or contingent, certain or conditional. Nothing in that body of doctrine, standing alone, sets any limit on how far into the future a transferor may project his intentions. A grantor could, in principle, direct the devolution of Blackacre through an indefinite series of contingencies extending for centuries, binding generations unborn to a scheme devised by a person long dead. The Rule Against Perpetuities is the common law's answer to that possibility. It is not a rule about the duration of ownership, nor a rule against long-lasting trusts as such, nor a rule forbidding restraints on alienation; it is a rule about the time within which contingent interests must become certain. This chapter develops the Rule in its classical form, examines the traps that made it notorious, surveys the statutory and judicial reforms that have transformed it in nearly every American jurisdiction, and concludes Part V by turning from ownership divided across time to ownership shared simultaneously.

1. The common-law Rule Against Perpetuities invalidates any contingent interest that is not certain to vest or fail within twenty-one years after the death of some life in being at the creation of the interest. Gray's formulation, adopted in substance by Restatement (First) of Property § 274 and carried forward with qualification by Restatement (Third) of Property (Wills and Other Donative Transfers) § 27.1, is the canonical statement of the classical Rule.
2. The Rule addresses remote vesting, not remote possession and not perpetual duration. An interest that vests within the period satisfies the Rule even though possession is postponed indefinitely; an interest that may vest outside the period fails even though possession, if it ever came, would come promptly.
3. The classical Rule is a rule of logical possibility, not of probability. Validity is tested at the moment of creation by asking what might happen, not what is likely to happen or what in fact happened. This “what-might-happen” test produced the fertile octogenarian, the unborn widow, and the administrative-contingency traps.
4. Grantor-retained interests are exempt from the Rule. Reversions, possibilities of reverter, and rights of entry were classified as vested at common law and therefore escaped the Rule entirely. Contingent remainders, executory interests, and remainders vested subject to open are subject to it. The exemption is a historical artifact rather than a policy judgment, and several jurisdictions have narrowed it by statute.
5. A class gift stands or falls as a whole under the all-or-nothing rule. Unless the class closes within the perpetuities period as to every possible member, the entire gift fails, even as to members whose interests were certain to vest promptly. Leake v. Robinson, 35 Eng. Rep. 979 (Ch. 1817). The rule of convenience frequently saves such gifts by closing the class early, but it is a rule of construction and not an exception to the Rule.
6. Powers of appointment are tested under distinct rules depending on their character. A general power presently exercisable is valid if it must become exercisable within the period; a special or testamentary power is valid only if it cannot be exercised beyond the period; and interests appointed under a special or testamentary power are measured from the creation of the power under the second-look doctrine.
7. The Rule was historically applied to commercial options and preemptive rights, with results widely criticized as inconsistent with its donative purpose. Restatement (Third) of Property (Wills and Other Donative Transfers) § 27.3 and the Uniform Statutory Rule Against Perpetuities § 4 exclude most commercial transactions from the Rule, relegating them to the doctrine of unreasonable restraints on alienation.
8. Wait-and-see reform replaces the what-might-happen test with observation of actual events. Under a wait-and-see regime an interest is not struck down at creation; validity is judged by whether the interest in fact vests within the permitted period, measured either by common-law lives or, under the Uniform Statutory Rule Against Perpetuities § 1(a)(2), by a flat ninety-year alternative period.
9. Judicial reformation — cy pres in the perpetuities context — empowers a court to reform a defective disposition to approximate the transferor's intention within the permitted period. Uniform Statutory Rule Against Perpetuities § 3; Restatement (Third) § 27.2. Reformation converts the Rule from a doctrine of forfeiture into a doctrine of correction.
10. A substantial minority of American jurisdictions have abolished or effectively suspended the Rule for interests held in trust, enabling the perpetual or dynasty trust. These statutes do not abandon the policy against dead-hand control so much as relocate it, substituting trustee powers of sale, decanting, modification, and termination for the temporal limit the Rule formerly supplied.
11. The Rule remains operative in modern practice through drafting, title examination, and choice of law. A perpetuities saving clause is standard in competent instruments; a title examiner must still evaluate old contingent interests under the law in force when they were created; and the governing-law clause of a long-term trust now frequently determines whether any perpetuities limit applies at all.

• State the common-law Rule Against Perpetuities in Gray's formulation and identify each operative element of the statement.
• Distinguish the Rule from the rule against restraints on alienation, the rule against accumulations, and the rule of convenience.
• Trace the emergence of the Rule from the medieval devices for perpetuating family landholding through the Duke of Norfolk's Case (1682) and its nineteenth-century consolidation.
• Identify which future interests are subject to the Rule and which are exempt, and explain the historical reason for the exemption of grantor-retained interests.
• Apply the what-might-happen test by identifying a validating life and reasoning from the moment of creation.
• Recognize and resolve the classical traps: the fertile octogenarian, the unborn widow, the administrative contingency, the age contingency, and the slothful executor.
• Apply the all-or-nothing rule to class gifts, and determine when the rule of convenience or a subclass analysis saves an otherwise invalid gift.
• Analyze powers of appointment under the distinct validity and second-look rules governing general, special, and testamentary powers.
• Evaluate the application of the Rule to commercial options and preemptive rights, and state the modern exclusion.
• Compare the principal reform strategies — immediate reformation, wait-and-see, USRAP's two-part rule, and outright abolition — and identify the policy trade-offs of each.
• Draft a perpetuities saving clause and explain its operation, its limits, and its interaction with reform statutes.
• Assess the recording, marketability, and title-examination consequences of interests that are or may be void under the Rule.

• Uniform Statutory Rule Against Perpetuities §§ 1–5 (Unif. Law Comm'n 1986, amended 1990).
• Uniform Probate Code §§ 2-901 to 2-906 (incorporating USRAP).
• Restatement (First) of Property §§ 274–296 (1944).
• Restatement (Third) of Property (Wills and Other Donative Transfers) §§ 27.1–27.3 (2011).
• Duke of Norfolk's Case, 3 Ch. Cas. 1, 22 Eng. Rep. 931 (Ch. 1682).
• Stephens v. Stephens, Cas. temp. Talb. 228, 25 Eng. Rep. 751 (Ch. 1736).
• Thellusson v. Woodford, 32 Eng. Rep. 1030 (Ch. 1805), aff'd, 4 Eng. Rep. 1087 (H.L. 1817).
• Cadell v. Palmer, 6 Eng. Rep. 956 (H.L. 1833).
• Leake v. Robinson, 35 Eng. Rep. 979 (Ch. 1817).
• Jee v. Audley, 29 Eng. Rep. 1186 (Ch. 1787).

• John Chipman Gray, The Rule Against Perpetuities §§ 1–30, 201–214, 369–411 (4th ed. 1942).
• Lewis M. Simes & Allan F. Smith, The Law of Future Interests §§ 1211–1298 (2d ed. 1956).
• Lewis M. Simes, Public Policy and the Dead Hand 32–63 (1955).
• W. Barton Leach, Perpetuities in a Nutshell, 51 Harv. L. Rev. 638 (1938).
• W. Barton Leach, Perpetuities: The Nutshell Revisited, 78 Harv. L. Rev. 973 (1965).
• W. Barton Leach, Perpetuities Reform by Legislation: England, 70 Harv. L. Rev. 1411 (1957).
• Thomas F. Bergin & Paul G. Haskell, Preface to Estates in Land and Future Interests 179–216 (2d ed. 1984).
• Roger A. Cunningham, William B. Stoebuck & Dale A. Whitman, The Law of Property §§ 3.18–3.25 (3d ed. 2000).
• 2 William Blackstone, Commentaries on the Laws of England *173–*175 (1766).
• 4 James Kent, Commentaries on American Law *267–*283 (1830).
• Frederick Pollock & Frederic W. Maitland, The History of English Law Before the Time of Edward I, vol. 2, at 21–29 (2d ed. 1898).
• S. F. C. Milsom, Historical Foundations of the Common Law 166–199 (2d ed. 1981).
• A. W. B. Simpson, A History of the Land Law 208–241 (2d ed. 1986).
• Sir John Baker, An Introduction to English Legal History 261–300 (5th ed. 2019).
• Jesse Dukeminier, A Modern Guide to Perpetuities, 74 Calif. L. Rev. 1867 (1986).
• Lawrence W. Waggoner, The Uniform Statutory Rule Against Perpetuities: The Rationale of the 90-Year Waiting Period, 73 Cornell L. Rev. 157 (1988).
• Jesse Dukeminier, James E. Krier, Gregory S. Alexander, Michael H. Schill & Lior Jacob Strahilevitz, Property 291–316 (10th ed. 2022).

The Rule Against Perpetuities is a rule of property law that invalidates a contingent future interest if, at the moment the interest is created, it is not certain to vest or to fail within twenty-one years after the death of a person then alive. Gray's celebrated formulation — “No interest is good unless it must vest, if at all, not later than twenty-one years after some life in being at the creation of the interest” — is not a statute and has never been enacted in that form, but it became the operative text of American perpetuities law during the century following the publication of his treatise in 1886, and courts continue to recite it verbatim. Restatement (First) of Property § 274 adopted it in substance. Restatement (Third) of Property (Wills and Other Donative Transfers) § 27.1 retains it as the baseline against which the modern reforms are measured.

Each element of the statement does independent work, and each is a frequent source of error. “No interest” means no contingent interest of the kinds identified in Part III; vested interests are outside the Rule altogether. “Is good” refers to validity at creation, not to enforceability at some later date. “Must vest” imposes a requirement of logical certainty rather than probability. “If at all” acknowledges that an interest satisfies the Rule if it is certain either to vest or to fail definitively within the period; the Rule requires resolution, not vesting. “Not later than twenty-one years after some life in being” defines the permitted period. “At the creation of the interest” fixes the moment of measurement: the delivery of a deed, the death of a testator, or, for a revocable trust, the moment the power of revocation lapses.

The Rule is therefore best understood as a limitation on the duration of contingency, not on the duration of ownership. A trust may endure for a century without offending the classical Rule, provided every beneficial interest under it vests within the period. Conversely, a single contingent gift that might vest a day beyond the period fails, though the arrangement it belongs to would have terminated within a generation. Confusing duration with contingency is the most common analytical error in this field, and it is the error that most frequently produces the mistaken assertion that a long-term trust is void.

Three policies are conventionally advanced in justification of the Rule, and they are not identical. The first is the limitation of dead-hand control. A transferor who may dictate the devolution of property indefinitely governs persons who never consented to his authority and who cannot adapt his scheme to circumstances he could not foresee. Simes, in Public Policy and the Dead Hand, treated this as the Rule's central justification: the living should govern the property of the living, and the balance struck by the Rule allows a transferor to provide for those he knows and for their children coming of age, but no further.

The second is alienability. Property burdened by outstanding contingent interests cannot be conveyed in fee by anyone, because no person or ascertainable combination of persons owns the whole. Contingent interests held by unborn or unascertained takers cannot be released or joined in a conveyance. The Rule limits the period during which land may be so fragmented that no marketable title can be assembled.

The third is the economic argument, developed principally in the twentieth century, that resources should be controlled by those with current information and current incentives. A fixed scheme devised generations earlier will misallocate capital, and the correction of that misallocation is costly. This argument has always sat uneasily with the modern trust, in which a trustee holds full powers of sale and reinvestment; the corpus of a perpetual trust is fully alienable even though the beneficial interests are not. The perpetual-trust statutes discussed in Part VIII rest largely on that observation, and the debate over their wisdom turns on whether the alienability rationale or the dead-hand rationale is treated as controlling.

It is essential to distinguish the Rule from three neighbors. The rule against unreasonable restraints on alienation invalidates provisions that forbid or penalize transfer; the Rule Against Perpetuities has nothing to say about a transfer restriction attached to a vested interest. The rule against accumulations limits the period during which trust income may be accumulated rather than distributed; it is a separate doctrine, statutory in most jurisdictions. The rule of convenience is a rule of construction that closes classes early; it frequently rescues gifts from the Rule but is not itself a perpetuities doctrine.

The Rule Against Perpetuities was not designed; it accumulated. Its history is the history of a long contest between landowners seeking to bind their land to their bloodline and courts seeking to keep land transferable. Chapter 8 traced the first phase of that contest. The conditional fee of the thirteenth century, construed by the royal courts as becoming alienable upon the birth of issue, was met by De Donis Conditionalibus (1285), which created the fee tail and preserved the entail against alienation. The entail was in turn defeated by the collusive common recovery recognized in Taltarum's Case (1472), which allowed the tenant in tail to bar the entail and convey a fee simple.

The Statute of Uses (1536) and the Statute of Wills (1540) transformed the terrain. By executing the use, the Statute of Uses converted equitable interests into legal ones and thereby validated as legal interests the springing and shifting limitations that equity had permitted. The Statute of Wills authorized devise of land and so allowed testators to create executory devises. Executory interests, unlike contingent remainders, were indestructible: they could not be defeated by the premature termination of a preceding estate, by merger, or by forfeiture. Purefoy v. Rogers, 2 Wms. Saund. 380 (1671), limited the reach of the new device by holding that a limitation capable of taking effect as a contingent remainder must do so, but the indestructible executory interest remained available wherever the remainder classification could not apply.

The consequence was structural. Before 1536 the destructibility doctrine had furnished a rough, unprincipled, but effective outer limit on remote contingencies: a contingent remainder that did not vest by the natural end of the preceding freehold simply died. After 1536 there was no such limit at all for executory interests. A grantor could now create a chain of shifting interests reaching indefinitely into the future, and nothing in the law of estates prevented it. The courts of Chancery, confronted with instruments of exactly that ambition, were compelled to invent a limit.

The Duke of Norfolk's Case, 3 Ch. Cas. 1, 22 Eng. Rep. 931 (Ch. 1682), is the origin of the modern Rule. Henry Frederick Howard, Earl of Arundel, settled the family estates in a scheme designed to keep the barony of Grostock in the hands of whichever son was not, at any given time, encumbered with the dukedom of Norfolk. His eldest son Thomas was of unsound mind; the settlement provided that if Thomas died without issue during the life of his brother Henry, the Grostock estates should shift from Henry to the next brother, Charles. Thomas did in fact die without issue, and Charles sued to enforce the shifting limitation.

Lord Nottingham upheld the interest. His reasoning matters more than the result. He rejected the argument that all executory limitations were void as perpetuities, and equally rejected the argument that all were valid. The question, he held, was whether the contingency was confined within a reasonable compass — here, the life of a person then living. “Where the contingency is limited to take effect after a life or lives in being,” he wrote, the limitation is good, for it is “not too remote.” When pressed to state where the boundary lay in the general case, he declined to draw it in advance: the courts would mark it out as cases arose, as they had marked out the boundaries of many other doctrines.

That is precisely what happened. The Rule was elaborated case by case over the following century and a half. Stephens v. Stephens, Cas. temp. Talb. 228 (Ch. 1736), added a period of twenty-one years after a life in being, on the analogy of the minority of an infant. Long v. Blackall, 101 Eng. Rep. 875 (K.B. 1797), and Cadell v. Palmer, 6 Eng. Rep. 956 (H.L. 1833), confirmed that the twenty-one years were a gross period, available whether or not any minority was actually involved. Thellusson v. Woodford, 32 Eng. Rep. 1030 (Ch. 1805) — the case of the merchant who directed accumulation of his fortune through all his living descendants — provoked the Accumulations Act 1800 and demonstrated that the Rule against remote vesting did not, by itself, restrain accumulation of income.

By the middle of the nineteenth century the doctrine was substantially complete but had never been stated in a single authoritative sentence. That task fell to John Chipman Gray, whose treatise, first published in 1886 and revised through four editions, distilled the case law into the formulation quoted at the head of this chapter. Gray's achievement was expository rather than legislative, but its influence has been so complete that American courts routinely treat his sentence as though it were a statute — including in jurisdictions whose actual statutes say something materially different.

The Rule was received in America as part of the common law, and Kent's Commentaries transmitted it to the antebellum bar substantially in its English form. American developments then diverged in two respects. First, several states adopted statutory substitutes early: the New York property revisions of 1830 replaced the Rule with a limitation on suspension of the power of alienation measured by two lives in being, a formulation later copied in Michigan, Minnesota, Wisconsin, and elsewhere and productive of a century of confusion, since a suspension rule and a vesting rule are not the same rule and do not invalidate the same interests. Second, the American law of charitable trusts developed exemptions broader than the English.

The reform era began in earnest with W. Barton Leach's Perpetuities in a Nutshell, 51 Harv. L. Rev. 638 (1938), which set out the classical traps with such clarity that they became impossible to defend. Leach's subsequent writing, and his account of English reform in Perpetuities Reform by Legislation: England, 70 Harv. L. Rev. 1411 (1957), pressed the argument that a rule invalidating dispositions on the strength of biologically impossible hypotheses served no policy whatever. Reform proceeded in four waves: specific statutory corrections of individual traps; the cy pres or reformation statutes; wait-and-see legislation, adopted first in Pennsylvania in 1947; and finally the Uniform Statutory Rule Against Perpetuities, promulgated in 1986 and now the majority position. The fifth wave — outright abolition for trust interests — began in the 1990s and is discussed in Part VIII.

The Rule applies only to contingent interests, and only to those contingent interests that the common law classified as capable of remote vesting. The classification developed in Chapters 12 through 14 therefore determines the Rule's application, and the point cannot be reached without it. Three categories of interest are subject to the Rule: contingent remainders, executory interests, and remainders vested subject to open. Three are exempt: reversions, possibilities of reverter, and rights of entry. The exemption also extends to remainders indefeasibly vested and to remainders vested subject to complete divestment, on the ground that such interests are already vested in the technical sense.

The exemption of grantor-retained interests is indefensible as a matter of policy and is universally acknowledged to be so. A possibility of reverter following a fee simple determinable may remain outstanding for centuries, fragmenting title exactly as an executory interest would; the only difference is that it is held by the grantor's remote successors rather than by a stranger's. The exemption survives because the classical taxonomy treated retained interests as never having left the grantor and therefore as vested by definition. Modern statutes have narrowed the practical consequence from the other direction: reverter-limitation and marketable-title acts, discussed in Chapter 13, extinguish stale reverters and rights of entry after a fixed period, achieving by a statute of repose what the Rule declines to achieve by classification.

The Rule requires vesting within the period; it does not require possession within the period, and it does not require distribution within the period. An interest vests, for perpetuities purposes, when the taker is ascertained and every condition precedent has been satisfied. Whether the taker will then wait fifty years for possession is immaterial. In “to A for life, then to A's first child for life, then to B,” B's remainder is indefeasibly vested at the moment of the conveyance even though possession may not arrive for a century.

Two refinements are essential. First, vesting in interest is distinguished from vesting in possession, and the Rule is concerned with the former. Second, a class gift is not regarded as vested for perpetuities purposes until the class has closed and every condition precedent has been satisfied as to every member — a stricter test than that applied for other doctrinal purposes, and the source of the all-or-nothing rule discussed in Part V. The mismatch between the two senses of “vested” is a persistent source of error: a remainder may be vested subject to open for purposes of alienability and acceleration, and simultaneously contingent for purposes of the Rule.

The permitted period is a life in being plus twenty-one years. The “life in being” need not be named in the instrument, need not have any beneficial interest under it, and need not be selected in advance; the analyst is entitled to search for any person alive at the creation of the interest whose life will validate the gift. A life so identified is a validating life, or, in the older usage, a measuring life. Cadell v. Palmer confirmed that the twenty-one years are a period in gross, running from the death of the validating life regardless of whether any minority is involved, and that periods of gestation are added where a beneficiary is in fact conceived but unborn.

The analytical method is therefore constructive rather than eliminative. One does not test every person alive in the world; one asks whether there exists any person, alive at creation, such that the interest is certain to vest or fail within twenty-one years of that person's death. If such a person exists, the interest is valid. If no such person exists, it is void. In the ordinary case the validating life is obvious: the life tenant, the beneficiaries' parent, or the class of persons whose deaths will close the class. The instrument may also designate an artificial set of measuring lives — the so-called royal-lives clause, upheld in England and generally in America provided the group is reasonably ascertainable.

The critical discipline is that the analysis is performed at the moment of creation and looks forward. Facts occurring afterward are irrelevant under the classical Rule. This is what Leach called the “what-might-happen” test, and it produces results that appear absurd because they are: the Rule strikes down gifts on the strength of hypotheses that will not occur and, in some cases, cannot occur.

Four traps are conventional, and a fifth is often added. Each arises from the interaction of the what-might-happen test with a legal presumption that departs from biological or commercial reality.

A fifth pattern, the “magic gravel pit,” concerns gifts conditioned on the exhaustion of a resource or the cessation of a use. A limitation “to the City so long as the land is used as a park, then to B” creates an executory interest in B that is void at common law, since the use might continue indefinitely. The consequence is not the invalidity of the whole conveyance but the striking of B's interest, leaving the City with a fee simple determinable and the grantor with a possibility of reverter — an outcome that defeats the transferor's intention while achieving nothing for the Rule's policy, because the reverter is itself perpetual.

A class gift is a gift to a group described by a collective term whose membership may increase or decrease until the class closes. Chapter 14 developed the classification consequences: each ascertained member takes a remainder vested subject to open, and the class closes physiologically when no further members can be born or, earlier, under the rule of convenience when any member becomes entitled to distribution. For perpetuities purposes a further and stricter rule applies.

Under the all-or-nothing rule of Leake v. Robinson, a class gift is valid only if the interest of every possible member is certain to vest or fail within the period. If the share of any potential member might vest too remotely, the entire gift fails — including the shares of members whose interests were certain to vest at once. The rule follows from the perpetuities conception of vesting: because the size of each member's share depends on the total number of members, no member's interest is regarded as vested until the class has closed. A gift that is one-tenth defective is wholly void.

Two mitigating doctrines operate at common law. The rule of convenience closes the class as soon as any member is entitled to demand possession, and because a class that closes within the period cannot admit remote members, it frequently validates gifts that would otherwise fail. The distinction must be kept precise: the rule of convenience is a rule of construction ascertaining the transferor's probable intention, and it applies unless the instrument directs otherwise; it is not a perpetuities savings doctrine, and it will not operate where the instrument expressly keeps the class open.

The second mitigating doctrine is the subclass rule, associated with American Security & Trust Co. v. Cramer, 175 F. Supp. 367 (D.D.C. 1959), and adopted by Restatement (Third) § 27.1 cmt. Where the instrument creates separate and independently determinable shares — as in a gift of income to A's children for their respective lives, with each child's share passing on that child's death to that child's issue — the gift to each subclass is tested independently, and the invalidity of one subclass does not defeat the others. Two specific exceptions to the all-or-nothing rule are also long established: gifts of a specified sum to each member of a class, and gifts to subclasses whose membership is fixed at a time certain.

The illustrations repay careful attention because they isolate the single variable that determines validity in the overwhelming majority of real disputes: whether the contingency attached to the class gift can be tied to the life of a person alive at creation. Where it can, the gift is good; where it floats free — an age above twenty-one, a generation beyond children, a widow not yet identified — it fails.

A power of appointment is an authority, conferred by a donor on a donee, to designate the persons who shall take property. The Rule applies to powers in two distinct operations: to the validity of the power itself, and to the validity of the interests created by its exercise. The applicable test differs according to the character of the power.

A general power presently exercisable — one exercisable by the donee in favor of himself, his estate, his creditors, or the creditors of his estate, at any time — is valid if it must become exercisable, if at all, within the period. The rationale is that such a power is the practical equivalent of ownership: the donee may at any moment appoint the property to himself, and property subject to it is therefore not withdrawn from commerce. A general testamentary power, by contrast, and every special power, is valid only if it cannot possibly be exercised beyond the period. The donee of such a power cannot reach the property for his own benefit, and the property remains tied up until the power is exercised or expires.

The distinction produces a familiar result: a special power conferred on an unborn person is void, since the unborn donee might exercise it more than twenty-one years after the death of all lives in being. A general presently exercisable power conferred on an unborn person is likewise void unless it must become exercisable within the period — for example, a power conferred on a person upon reaching twenty-one.

Interests created by the exercise of a general power presently exercisable are measured from the date of exercise, because the donee is treated as the effective owner. Interests created by the exercise of a general testamentary power or a special power are measured from the creation of the power under the relevant-time doctrine, on the theory that the donee is merely completing a disposition begun by the donor.

The severity of that rule is tempered by the second-look doctrine. Although the period runs from the creation of the power, the court examines the facts as they exist at the date of exercise in determining what might happen thereafter. A gift that would have been void if tested purely on the facts at creation may therefore be sustained if the intervening events have eliminated the remote possibility. The doctrine is a limited and pragmatic incursion of wait-and-see reasoning into the classical Rule, and it long predates the reform statutes.

Restatement (Third) of Property (Wills and Other Donative Transfers) §§ 27.1–27.2 and USRAP § 1 restate these rules with modifications. Under USRAP, a nongeneral or testamentary power is valid if it is exercised within ninety years of creation or if it satisfies the common-law test; and the second-look doctrine is largely superseded, because actual events are consulted in every case.

The Rule was devised to control family settlements, but its language is not confined to donative transfers, and courts applied it for a century to options to purchase land, rights of first refusal, and other commercial interests. An option to purchase, unlimited in time or exercisable on a remote contingency, creates an equitable interest in the optionee that may vest beyond the period; on the classical analysis it is void. The leading American decisions applying the Rule to options include those invalidating options in gross of unlimited duration and options exercisable upon the expiration of a long-term lease.

The application drew sustained criticism. An option or preemptive right does not fragment title among unborn takers; it does not represent dead-hand control; and it is typically part of a bargained commercial exchange in which both parties are living and represented. Invalidating it under a rule directed at family perpetuities defeats a live commercial expectation and serves none of the Rule's three policies. Where the objection to a long option is that it impairs marketability, the appropriate doctrine is the rule against unreasonable restraints on alienation, which is capable of evaluating the restraint's reasonableness rather than applying a mechanical temporal test.

Modern law has largely accepted that criticism. USRAP § 4(1) expressly excludes from the statutory rule a nondonative transfer of property, subject to enumerated exceptions; Restatement (Third) § 27.3 adopts the same position and refers commercial arrangements to the law of restraints on alienation. Two important qualifications survive. Options appurtenant to a leasehold — a tenant's option to purchase the leased premises, or to renew — have generally been held outside the Rule even at common law, because they encourage rather than discourage improvement of the property. And in jurisdictions that have not adopted USRAP or its equivalent, the classical Rule continues to apply to options in gross, and a title examiner must evaluate the instrument under the law in force when the option was created.

The practical drafting response, in any jurisdiction whose position is uncertain, is to state an express outside date for exercise falling within twenty-one years of execution. The device costs nothing and removes the question entirely.

Perpetuities reform in the United States has proceeded along four lines, and most jurisdictions have adopted some combination of them. They are best understood as answers to distinct questions: whether to correct particular traps, whether to consult actual events, whether to reform defective instruments, and whether to retain the Rule at all.

The Uniform Statutory Rule Against Perpetuities, promulgated by the Uniform Law Commission in 1986 and amended in 1990, is the dominant modern statement. It is incorporated into the Uniform Probate Code at §§ 2-901 to 2-906 and has been enacted in a substantial majority of states. Its architecture is a two-part rule.

Under § 1(a)(1), a nonvested property interest is valid if, when it is created, it is certain to vest or terminate within the common-law period. That clause preserves the classical Rule as a safe harbor: an instrument valid at common law is valid under USRAP, and the great body of existing analysis remains usable. Under § 1(a)(2), an interest that fails that test is nonetheless valid if it in fact vests or terminates within ninety years after its creation. The ninety-year period is not a substitute measuring life; it is an alternative wait-and-see period, chosen by Waggoner and the drafting committee as an actuarial approximation of the average period produced by common-law measuring lives in typical family dispositions.

Section 3 supplies the reformation power: on the petition of an interested person, a court shall reform a disposition that violates § 1 in the manner that most closely approximates the transferor's manifested plan of distribution and falls within the ninety years allowed. Reformation is available when the ninety-year period expires with the interest still unvested, when a class gift has not closed, and when an interest would otherwise become void. Section 4 excludes nondonative transfers, most commercial arrangements, and certain fiduciary and employee-benefit interests. Section 5 governs application to instruments executed before the statute's effective date.

The choice of a flat period drew criticism from Dukeminier, who argued that ninety years is longer than most measuring-life periods in practice and that USRAP therefore extends rather than restrains dead-hand control. The debate is largely academic in jurisdictions that have since adopted perpetual-trust legislation, but it remains relevant in the majority of states, where USRAP is the operative rule.

Beginning in the 1990s a number of states repealed the Rule as applied to interests in trust, or extended the permitted period to several hundred years, or permitted the settlor to opt out by directing that the trustee hold a power of sale. The immediate impetus was the federal generation-skipping transfer tax: property held in a trust that never distributes outright can escape transfer taxation at each successive generation, and the exemption amount, once allocated, shelters the entire future growth of the trust. States with favorable trust statutes attracted trust business, and a competitive process followed.

The resulting instruments — dynasty trusts — do not violate any policy of alienability, since the trustee holds unrestricted power to sell and reinvest the corpus. They do, however, extend dead-hand control indefinitely, which is precisely what the Rule existed to prevent. The modern American answer is that the limit is now supplied by the law of trust modification rather than by the law of estates: the Uniform Trust Code's provisions on modification, termination, deviation, and decanting allow beneficiaries and courts to adapt an obsolete trust to changed circumstances. Whether that substitution is adequate is a live question, treated at length in the Society's trust-law volumes.

Choice of law is now a practical determinant of perpetuities exposure. The governing law of a trust is ordinarily the jurisdiction designated by the settlor, provided there is a substantial relationship — typically satisfied by the situs of the trustee or of the administration. A settlor domiciled in a USRAP jurisdiction may therefore establish a perpetual trust under the law of a jurisdiction that has abolished the Rule. Limits exist: the validity of an interest in land is generally governed by the law of the situs, and a state's strong public policy may in principle displace the designated law, although reported decisions invalidating a properly established out-of-state perpetual trust are rare.

For interests in land, the classical Rule therefore remains operative in a way it does not for trusts of personal property. A conveyance of an interest in real property is tested under the perpetuities law of the state where the land lies, regardless of the parties' designation, and a title examiner must apply the law in force at the time of the conveyance rather than the law in force today.

A perpetuities saving clause is a provision that terminates the trust and distributes the property outright at the expiration of a stated period, so that no interest can possibly vest too remotely. It operates by supplying an express outside limit rather than by curing the defect in any particular gift, and it is effective in every jurisdiction, including those that have not adopted any reform statute. Its inclusion is a minimum standard of competence in drafting any instrument creating a future interest.

A conventional clause designates a set of measuring lives — commonly the descendants of a named ancestor living at the effective date — and directs that, notwithstanding any other provision, the trust shall terminate and the principal be distributed to the persons then entitled to income twenty-one years after the death of the last survivor. A royal-lives clause substitutes a public and easily verified group. Where the governing jurisdiction has abolished the Rule for trusts, the clause is drafted conditionally, so that it operates only if the Rule is held applicable.

Five further drafting practices follow from the analysis in this chapter. State survivorship expressly rather than relying on construction. Fix age contingencies at twenty-one, or provide that any greater age shall be reduced to twenty-one if necessary to comply with the Rule. Define “widow” or “spouse” as a person living at the effective date of the instrument where the unborn-widow problem could arise. Give commercial options an express outside exercise date. And state a governing law, with a substantial-relationship anchor, where the intended duration of the trust makes the point material.

A perpetuities defect appears in a title search as an outstanding contingent interest of uncertain validity. Three questions must be answered. First, what law governed at the time the interest was created — the classical Rule, a specific-correction statute, wait-and-see, or USRAP? Perpetuities statutes are almost universally prospective, and USRAP § 5 expressly addresses pre-enactment instruments; an interest created in 1950 is tested under the law of 1950. Second, if the interest is void, what is the consequence for the remaining dispositions? Striking an executory interest ordinarily leaves the preceding estate standing as a determinable or absolute fee, with the residue of ownership in the transferor or his successors. Third, is the record capable of being cleared without litigation?

Marketable-title acts and reverter-limitation statutes, examined in Chapter 13, resolve a large proportion of these cases by extinguishing ancient interests after a fixed period from the root of title. Where they do not, a quiet-title action or a declaratory proceeding is the ordinary remedy, and in a wait-and-see or USRAP jurisdiction the reformation power of § 3 may be invoked in the same proceeding. Title insurers commonly except from coverage any interest whose perpetuities validity is unresolved, so the practical effect of an unremedied defect is to render the title uninsurable rather than to defeat it outright.

In transactional practice the most frequent modern encounter with the Rule is not a family settlement at all but a recorded option, right of first refusal, or repurchase right of indefinite duration in a commercial chain of title. Counsel should determine whether the jurisdiction has adopted the USRAP § 4 exclusion, and if it has not, whether the instrument's duration can be brought within the period by amendment before closing.

England, where the Rule originated, has moved in the opposite direction from the American trust states. The Perpetuities and Accumulations Act 1964 introduced wait-and-see, a fixed alternative period of up to eighty years, statutory presumptions of infertility, and age reduction. The Perpetuities and Accumulations Act 2009 went further: it confined the Rule to successive estates and interests arising under wills and trusts, removed it from commercial arrangements and most options entirely, abolished the measuring-life apparatus, and substituted a single fixed perpetuity period of 125 years. English law thus retains a genuine temporal limit on dead-hand control while eliminating the classical traps and the commercial misapplication.

Civil-law systems approach the problem differently. Because the fideicommissum — the successive substitution of heirs — was restricted or abolished in most nineteenth-century codifications, continental law generally limits successive substitutions to one or two degrees rather than by a period of years. The functional result resembles the policy of the Rule without any of its machinery.

Within the United States the picture is now genuinely fragmented, and the fragmentation is itself a doctrinal fact of consequence. A substantial majority of states apply USRAP or a close analogue; a significant group have abolished the Rule for trust interests or extended the period to several centuries; a small number retain the unmodified common-law Rule; and a residue retain nineteenth-century suspension-of-alienation statutes that are not perpetuities statutes at all. No general statement about “the American Rule” is now accurate without identifying the jurisdiction.

1. That the Rule limits how long a trust may last. It does not. It limits how long an interest may remain contingent. A trust whose beneficial interests all vest at creation may endure for as long as its terms provide without offending the classical Rule.
2. That the Rule is a restraint-on-alienation doctrine. The two are distinct. A direct restraint on the transfer of a vested fee is void as a restraint on alienation regardless of duration; a contingent interest that may vest too remotely is void under the Rule regardless of whether it impedes transfer.
3. That the Rule looks to what actually happened. Under the classical Rule it does not; validity is determined at creation on the basis of logical possibility. Only under wait-and-see and USRAP are actual events consulted, and only in the manner those regimes specify.
4. That vesting means taking possession. Vesting in interest is the operative concept. Postponed possession does not offend the Rule.
5. That the measuring life must be named in the instrument or must be a beneficiary. Neither is required. Any person alive at creation may serve as a validating life.
6. That grantor-retained interests are subject to the Rule. Reversions, possibilities of reverter, and rights of entry are exempt. Their staleness is addressed instead by reverter-limitation and marketable-title acts.
7. That the rule of convenience is a perpetuities doctrine. It is a rule of construction determining when a class closes. It frequently rescues class gifts from the Rule, but it operates on the transferor's presumed intention and yields to a contrary direction.
8. That USRAP abolished the common-law Rule. USRAP § 1(a)(1) preserves the common-law test as a safe harbor and adds an alternative ninety-year period. It supplements; it does not repeal.
9. That perpetual-trust legislation has made the Rule irrelevant. It remains fully operative for legal interests in land, for instruments created before the reform statutes, in jurisdictions that have not abolished it, and in every case where a title examiner must evaluate a historical conveyance under the law then in force.
10. That a perpetuities violation voids the entire instrument. Only the offending interest is struck, and the remaining dispositions stand unless the invalid gift is so integral that the transferor's plan cannot be carried out without it — the doctrine of infectious invalidity, which is applied sparingly.

The Rule Against Perpetuities limits the period during which a property interest may remain contingent. In Gray's formulation, no interest is good unless it must vest, if at all, not later than twenty-one years after some life in being at the creation of the interest. It arose in the Duke of Norfolk's Case (1682) as the Chancery's response to the indestructible executory interest created by the Statute of Uses (1536) and the Statute of Wills (1540), was elaborated case by case through Stephens v. Stephens (1736) and Cadell v. Palmer (1833), and was reduced to canonical form by Gray in 1886.

The Rule reaches contingent remainders, executory interests, and remainders vested subject to open. It does not reach reversions, possibilities of reverter, rights of entry, or remainders otherwise vested. It requires vesting, not possession, and it tests validity at creation by logical possibility rather than by probability. That test produced the fertile octogenarian, the unborn widow, the administrative contingency, and the age contingency exceeding twenty-one — traps that invalidated dispositions on hypotheses no one believed. Class gifts stand or fall as a whole under Leake v. Robinson, subject to the rule of convenience and the subclass doctrine. Powers of appointment are tested by rules that turn on whether the power is general and presently exercisable, and the second-look doctrine tempers the measurement of appointed interests from the creation of the power.

Commercial options and preemptive rights were long subjected to the Rule with results indefensible on any of its policies; USRAP § 4 and Restatement (Third) § 27.3 now exclude most nondonative transfers and refer them to the law of restraints on alienation. Reform has proceeded by specific statutory correction, by wait-and-see, by judicial reformation, and in a substantial group of states by abolition for interests in trust. The Uniform Statutory Rule Against Perpetuities preserves the common-law test as a safe harbor, adds a ninety-year alternative period, and supplies a reformation power. Perpetual-trust legislation has relocated the constraint on dead-hand control from the law of estates to the law of trust modification, and has made choice of law a determinant of perpetuities exposure. In practice the Rule is managed by a saving clause, by fixing ages at twenty-one, by defining spousal terms, by dating options, and by careful examination of the law in force when a historical interest was created.

Part V is now complete. Chapters 12 through 15 examined ownership divided across time: the framework of future interests, the interests retained by a transferor, the remainders created in transferees, and the temporal limit the law imposes on contingency. Each of those chapters assumed a single owner at each point along the timeline. Part VI turns to a different division of the same fee — not ownership successive in time, but ownership shared simultaneously by two or more persons, each with a concurrent right to possess the whole. Chapter 16 accordingly begins the study of concurrent ownership with the tenancy in common, the joint tenancy, and the tenancy by the entirety.

• John Chipman Gray, The Rule Against Perpetuities §§ 1–30, 201–214, 369–411 (4th ed. 1942).
• Lewis M. Simes & Allan F. Smith, The Law of Future Interests §§ 1211–1298 (2d ed. 1956).
• Lewis M. Simes, Public Policy and the Dead Hand 32–63 (1955).
• W. Barton Leach, Perpetuities in a Nutshell, 51 Harv. L. Rev. 638 (1938).
• W. Barton Leach, Perpetuities: The Nutshell Revisited, 78 Harv. L. Rev. 973 (1965).
• Jesse Dukeminier, A Modern Guide to Perpetuities, 74 Calif. L. Rev. 1867 (1986).
• Lawrence W. Waggoner, The Uniform Statutory Rule Against Perpetuities: The Rationale of the 90-Year Waiting Period, 73 Cornell L. Rev. 157 (1988).
• Thomas F. Bergin & Paul G. Haskell, Preface to Estates in Land and Future Interests 179–216 (2d ed. 1984).
• Roger A. Cunningham, William B. Stoebuck & Dale A. Whitman, The Law of Property §§ 3.18–3.25 (3d ed. 2000).
• 2 William Blackstone, Commentaries on the Laws of England *173–*175 (1766).
• 4 James Kent, Commentaries on American Law *267–*283 (1830).
• A. W. B. Simpson, A History of the Land Law 208–241 (2d ed. 1986).
• Sir John Baker, An Introduction to English Legal History 261–300 (5th ed. 2019).
• S. F. C. Milsom, Historical Foundations of the Common Law 166–199 (2d ed. 1981).
• Restatement (First) of Property §§ 274–296 (1944).
• Restatement (Third) of Property (Wills and Other Donative Transfers) §§ 27.1–27.3 (2011).
• Uniform Statutory Rule Against Perpetuities §§ 1–5 (Unif. Law Comm'n 1986, amended 1990); Uniform Probate Code §§ 2-901 to 2-906.
• Perpetuities and Accumulations Act 1964, c. 55 (Eng.); Perpetuities and Accumulations Act 2009, c. 18 (Eng.).