At the intersection of incorporation-by-reference doctrine in the testamentary context and trust jurisprudence are several traps for unwary estate planners and trial lawyers. The doctrine sets forth conditions that must be met before an unattested writing, one that has not been executed in accordance with the statute of wills, may complete the terms of a will: (1) the writing must be in existence when the will is executed, i.e., signed, witnessed, etc.; (2) the will must manifest an intention to incorporate the unattested writing; and (3) the unattested writing must be identified with reasonable certainty. The UPC would do away with a fourth black-letter condition, namely that the will must expressly refer to the extrinsic writing as being in existence at the time of execution. Thus, the common-law doctrine of incorporation by reference cannot validate the transfer of a testator/settlor’s probate property to the trustee of his amendable inter vivos trust. Why? Because the writing that ultimately governs the administration of the entrusted property might not come into existence until after will is executed. It took another common-law doctrine, that of independent legal significance, to validate testamentary additions to trusts that are amendable by the testator/settlor between the time when he executes his will and the time he dies. See generally §8.15.9 of Loring and Rounds: A Trustee’s Handbook (2026) (the doctrine of independent legal significance), which section is reproduced in the appendix below.
In the estate-planning context the doctrine of independent legal significance has largely sidelined the doctrine of incorporation by reference. Still, some estate planners employ incorporation as a fallback to cover the contingency of the inter vivos trust being unavailable to receive the pour-over from the probate estate should the inter vivos trust be invalidated for whatever reason. It works this way: The will provides that in the event the inter vivos trust is not in existence at the time of testator’s death to receive the pour-over, the dispositive language of the inter vivos trust instrument, not the trust itself, is incorporated by reference into the will as that language reads at the time the will is executed. (But see UPC §2-513, providing that items of tangible personal property may be disposed of by reference in a will to a future writing having no independent legal significance.) These unattested writings then become the terms of a testamentary trust that is funded with the property that would have poured over to the inter vivos trust. The doctrinally challenged practitioner who labors under the misconception that the revocable inter vivos trust relationship itself has been relocated via incorporation into the will risks tripping up professionally at some point. As noted, it is just a “screen shot” of the relevant wording in the amendable inter vivos trust’s governing instrument that has either metaphorically or physically been made a part of the text of the will. Again, the “screen shot” is taken at the time the will is executed.
Here is a practical example of how conceptual confusion as to what is being incorporated into the will can trip up the unwary estate planner: Assume settlor of a revocable inter vivos trust wishes to eliminate X as one of the three designated beneficiaries. The settlor’s associated will has a testamentary-trust fallback provision. The settlor has had a falling out with X. Counsel supervises revocation of the inter vivos trust, but neglects to deal with the will’s dispositive provisions. X is still a designated beneficiary of the fallback testamentary trust. Lucky X.
Here is a practical example of how conceptual confusion can trip up the unwary trial lawyer: Assume X had unduly influenced the settlor to establish a revocable inter vivos trust under which X is treated more favorably than his two siblings. The two siblings retain counsel to petition to have the trust voided such that the residuary pour-over lapses, passing under the laws of intestacy to all three siblings equally. In the litigation complaint and at trial only the inter vivos trust is contested. As the two siblings would take under the fallback testamentary trust exactly what they are designated to take under the inter vivos trust, the appellate court determines that they lack standing to contest the inter vivos trust. The will and its terms also should have been contested at trial, and within the period of the applicable short state of limitations. That is the takeaway from Shippert v. Shippert, 717 S.W.3d 609 (Missouri App. 2025). Again, lucky X. But wait, not so fast. The two siblings may not be time-barred from bringing a Uniform Trust Code §415 petition to reform the inter vivos trust. Cf. https://analytics.jdsupra.com/content/detail_view/e92ef3b8-120d-4b36-8fc0- 9fefb8fb6bb4/reader/.
Appendix
§8.15.9 Doctrine of [Facts of, Acts of, Events of] Independent Legal Significance [from Loring and Rounds: A Trustee’s Handbook (2026)].
The common law doctrine of [facts of, acts of, or events of] independent legal significance in its most common manifestation is a gloss on the statute of wills.299 Most wills statutes provide in part that for a will to be valid it must be in writing and signed by the testator and two witnesses. What if a will contains a bequest to “those in my employ at the time of my death”? Would an employee who was hired after the will was signed and witnessed be entitled to take? Under the common law doctrine of independent legal significance he would.300 This is because the acts of hiring and firing are acts whose significance are independent of the will.301 The preparation of a post-execution unattested writing purporting to set forth additional takers under the will, however, would not be such an act as its sole purpose would be to “complement” the will.302 An early invocation of the doctrine may be found in an 1838 decision of the Chancellor in the case of Stubbs v. Sargon.303
The Restatement (Third) of Property, which gathers “facts of, or acts of, or events of” under the umbrella term “external circumstances,” confirms that the doctrine is not about motive: “An external circumstance has independent legal significance if it is one that would naturally occur or be done for some reason other than the effect it would have on the testamentary disposition, notwithstanding that it might occur or be done, or did occur or was done, for the purpose of affecting the testamentary disposition.”304
The UPC codifies the doctrine's application in the wills context: “A will may dispose of property by reference to acts and events that have significance apart from their effect upon the dispositions made by the will, whether they occur before or after the execution of the will or after the testator's death. The execution or revocation of another individual's will is such an event.”305
The trustee needs to be concerned about the doctrine primarily in the context of testamentary pour overs to revocable inter vivos trusts.306 Let us take the following situation: A will provides that the residue of the testator's estate shall be distributed to the trustee of a certain revocable inter vivos trust to be held in accordance with the terms of said trust, “as from time to time amended.”307 Would the traditional wills statute permit the residue to be administered in accordance with the terms of the trust had the trust been, say, token funded after the pour-over will’s execution (signing and witnessing)? Under the doctrine of independent legal significance, it would not.308 The devise would lapse.309 Would the traditional wills statute permit the residue to be administered in accordance with the terms of a trust that had been amended by a writing of the testator after the will had been executed? Under the doctrine of independent legal significance, it would.310 Because the revocable inter vivos trust is a relationship of independent legal significance, i.e., independent of the will, it follows that trust amendments, like hirings and firings, are the product of acts of independent legal significance.311 In many states the doctrine has been adopted or codified through legislation.312 Unless a statute provides otherwise, the revocable inter vivos trust would need to have been funded with at least a token amount prior to the pour-over will’s execution for it to have independent legal significance. Token funding in the trust context is taken up generally in §8.15.100 of this handbook. In §2.2.1 of this handbook we consider the statutory evisceration of the doctrine of independent legal significance in the context of revocable inter vivos trusts with associated pour-over wills, a process that began in earnest in the second half of the twentieth century on this side of the Atlantic.
The doctrine of independent legal significance also can rear its head in the estate tax context. Say a settlor establishes an irrevocable inter vivos trust for the benefit of his children, including children conceived or adopted after the trust is funded. The settlor dies. Is the subject property part of his federal gross estate for tax purposes? The argument for inclusion is that he retained a power to change the beneficial interests of the trust by conceiving or adopting children.313 The argument against inclusion, which is the argument that is likely to carry the day, is that “the act of bearing or adopting children is an act of independent significance, the incidental and collateral consequence of which is to add the child as beneficiary to the trust.”314
To the extent an exercise of an inter vivos power of appointment created under the terms of a power grantor's will is enforceable, it is not on account of the doctrine of independent legal significance. Rather, the exercise would be enforceable “on the theory that the exercise relates back and becomes part of the … [power-grantor's]… will, even if the writing exercising the power is not executed in accordance with the statutory formalities for wills.”315 The power of appointment is discussed generally in §8.1.1 of this handbook.
2991A Scott on Trusts §54.2.
3001A Scott on Trusts §54.2.
3011 Scott & Ascher §7.1.2.
3021A Scott on Trusts §54.2. “A devise to the persons named or of the property identified in an unattested writing to be prepared by the testator in the future has no independent significance, and is invalid unless authorized by statute or unless enforceable as a secret trust.” Rest. (Third) of Property (Wills and Other Donative Transfers) §3.7 cmt. e. Secret trusts are taken up in §9.9.6 of this handbook.
303Stubbs v. Sargon (1838) 3 My. & Cr. 507, 40 Eng. Rep. 1022 (Ch.).
304Rest. (Third) of Property (Wills and Other Donative Transfers) §3.7 cmt. a.
305UPC §2-512 (events of independent significance).
3061A Scott on Trusts §54.3.
307See generally Res. (Third) of Trusts §19 cmt. e.
308See, e.g., Second Bank-State St. Tr. Co. v. Pinion, 170 N.E.2d 350 (Mass. 1960). 309See generally §8.15.55 of this handbook (lapse).
3101A Scott on Trusts §54.3.
3111A Scott on Trusts §54.3. See generally Second Bank-State St. Tr. Co. v. Pinion, 341 Mass. 366, 170 N.E.2d 350 (1960). Massachusetts has since codified its doctrine of independent legal significance. See Mass. Gen. Laws ch. 190B, §2-512.
312See 1A Scott on Trusts §54.3. For a compilation of state statutes codifying the doctrine of independent legal significance in the context of inter vivos trusts and associated pour-over wills, see Jeffrey A. Schoenblum, Multistate Guide to Estate Planning 5-45 through 5-59 (Table 5.02) (CCH 2008).
313See I.R.C. §2036(a)(2) (providing that the value of the gross estate shall include the value of any interest in property transferred by a decedent if the decedent has retained for life the right, alone or in conjunction with any person, to designate the persons who shall possess or enjoy the property or the income therefrom); I.R.C. §2038(a)(1) (providing that the value of the gross estate shall include the value of all property transferred by the decedent if the enjoyment of the property was subject to change at his death through the exercise of a power by the decedent, alone or in conjunction with any person, to alter, amend, revoke, or terminate). See generally §8.9.4 of this handbook (tax-sensitive powers).
314Rev. Rul. 80-255.
315Rest. (Third) of Property (Wills and Other Donative Transfers) §3.7 cmt. e.
