An executory interest is any future estate in land which is not a reversion or a remainder. At common law, therefore, such estates were impossible, for the fee simple could not be granted to a person from a future date, unless that date was the termination of some smaller estate.

If, however, the land came within the jurisdiction of the Court of Chancery, these rules were not applied.

Since the courts of law refused to recognize uses and trusts or wills of land, all matters relating thereto were decided by equitable rules; hence either by means of a will, or by means of a use, future estates in fee simple could be created to commence at any future time or to terminate upon the happening of any future event, subject only to the rule against perpetuities.

Executory interests are, therefore, of two kinds: -

(1) Shifting and springing uses.

A very common example of a shifting use occurs in marriage settlements. The settlement is usually made before the marriage (for otherwise there is no consideration); and provision should therefore be made for the land remaining the property of the settlor, if the marriage does not take place. Thus -

A (the settlor) grants land to T and his heirs to the use of A and his heirs until the marriage of B and C, and, after the solemnization thereof, to the use of B for life, with remainder to the use of the sons of the marriage in tail, etc. (a).

The result of this was, in early times, that the fee simple passed to T, and the common law courts would not recognize any of the other provisions of the settlement: but the Court of Chancery compelled T to hold his legal estate to the use of A until the marriage, and then to the use of B and his children, etc.

Legal estates can now be given by means of a shifting use. For since the Statute of Uses the person who has the use has the legal estate.

Thus, in the last example, A gets the legal estate in fee simple; but, on the happening of the marriage, the fee simple passes away from A, and vests in B for life, etc.

T has no estate at all (b).

(2) Executory devise. Example -

A testator devises land to his daughter if she shall attain 21 or marry. The testator dies when daughter is aged 10. This is an executory devise to the daughter. Until the daughter reaches 21 or marries, the land is undisposed of, and vests in the testator's eldest son in fee simple, but, on the happening of either of those events, the fee simple vests in the daughter.

Executory interests being free from the common law rules which restricted the creation of contingent remainders, have always been especially liable to be destroyed by the rule against perpetuities. The very greatest care should therefore be taken, when creating executory interests, to ensure that the future estate must in every possible event vest within a life in being and 21 years thereafter.

(a) See the form of a settlement on p. 332.

(b) Before 1860 T was said to have a scintilla juris, or mere spark of seisin, left in him, in order that he might be " seised to the use " of B when the marriage took place, and thus enable the Statute of uses to apply.