A Tax Code Cross-Reference Has Pointed Nowhere Since 1988
Title 26, executed. A note after part 2, which applied the amending instructions of P.L. 119-21 to the Code one by one.
Five internal cross-references in the Internal Revenue Code do not match the provisions or the words they name. The oldest, in §42(j)(5)(C)(i), has pointed to a clause that does not exist since November 10, 1988; two more date from July 30, 2008, and two from December 22, 2017. None of the five carried an editorial note in the United States Code. We sent them to the Office of the Law Revision Counsel, the office that prepares the Code, on October 22, 2026. The Office has told us that it has added a footnote and a References in Text note at each of the five, for the next release point of the online Code. The words Congress enacted stay unchanged; that is what an editorial note is for.
Everything below can be checked against the Code's own amendment notes and the Statutes at Large. The links are at the end.
What a dangling reference looks like
Section 42 is the low-income housing credit. Subsection (e)(3)(B) reads:
In the case of a building acquired by the taxpayer from a governmental unit, at the election of the taxpayer, subparagraph (A)(ii)(I) shall not apply and the credit under this section for such rehabilitation expenditures shall be determined using the percentage applicable under subsection (b)(2)(B)(ii).
Until 2008, subsection (b)(2)(B)(ii) was the 30 percent present-value rate. On July 30, 2008, §3002(a)(1) of the Housing and Economic Recovery Act (P.L. 110-289, 122 Stat. 2879) amended §42(b) "by striking paragraph (1), by redesignating paragraph (2) as paragraph (1), and by inserting after paragraph (1), as so redesignated, the following new paragraph", the minimum 9 percent credit rate. The 30 percent rule became (b)(1)(B)(ii). The new (b)(2)(B) reads "which is not federally subsidized for the taxable year" and has no clauses. The reference in (e)(3)(B) was not conformed. A reader who knows the history reads "(b)(1)(B)(ii)"; the text says something else.
The five
| Provision | Reference as written | Where it pointed, and what happened | Mismatch since |
|---|---|---|---|
| §42(e)(3)(B) | "subsection (b)(2)(B)(ii)" | the 30 percent rate, now (b)(1)(B)(ii); today's (b)(2)(B) has no clauses | July 30, 2008 — P.L. 110-289, §3002(a)(1), 122 Stat. 2879 |
| §42(i)(3)(C)(ii) | "subsection (d)(2)(D)(iii)" | the definition of "related person", redesignated (d)(2)(D)(ii); (D) has no clause (iii) | July 30, 2008 — P.L. 110-289, §3003(e), (g)(2), 122 Stat. 2882 |
| §42(j)(5)(C)(i) | "subparagraph (B)(i)" | (B) was rewritten as one sentence with no clauses | November 10, 1988 — P.L. 100-647, §4004(a), 102 Stat. 3644 |
| §642(b)(2)(C)(iii)(II) | "the $4,150 amount in subparagraph (A)" | subparagraph (A) allows a $100 deduction; the $4,150 is in subclause (I) of the same clause | December 22, 2017 — enacted this way by P.L. 115-97, §11041(b), 131 Stat. 2082 |
| §877(a)(2) | "substituting '2003' for '1992' in subparagraph (B) thereof" (of §1(f)(3)) | §1(f)(3)(B) read "the CPI for the calendar year 1992" until paragraph (3) was replaced; the base year now sits in (A)(ii) as "2016", and (B) is a different rule | December 22, 2017 — P.L. 115-97, §11002(a), 131 Stat. 2059 |
1988. As enacted in 1986, §42(j)(5)(B) applied the partnership recapture rule to partnerships with 35 or more partners and had numbered clauses, and §42(j)(5)(C)(i) said that "for purposes of subparagraph (B)(i), a husband and wife (and their estates) shall be treated as 1 partner." The Technical and Miscellaneous Revenue Act of 1988 rewrote (B) as a single sentence: "This paragraph shall apply to any partnership which has 35 or more partners unless the partnership elects not to have this paragraph apply." The clause went; the reference to it stayed. Almost thirty-eight years.
2017, born broken. Section 11041(b) of P.L. 115-97 added clause (iii) to §642(b)(2)(C), the deduction for a qualified disability trust, with the words "the $4,150 amount in subparagraph (A) shall be increased in the same manner as provided in section 6334(d)(4)(C)". Subparagraph (A) of that paragraph says "a trust shall be allowed a deduction of $100". The $4,150 is the amount the same clause substitutes for the exemption amount in subclause (I). The reference has never resolved; the amount is indexed and published by the IRS each year on the reading that makes sense.
2017, broken by a neighbour. Section 877(a)(2) was rewritten in 2004 (P.L. 108-357, §804(a)(1), 118 Stat. 1569). It sets a $124,000 income-tax threshold for expatriates and indexes it "by the cost-of-living adjustment determined under section 1(f)(3) for such calendar year by substituting '2003' for '1992' in subparagraph (B) thereof". In 2004 that subparagraph read "the CPI for the calendar year 1992", so the substitution moved the base year to 2003. P.L. 115-97 replaced §1(f)(3) with the chained-CPI formula: the base year, "2016", now sits in subparagraph (A)(ii), and subparagraph (B) is "Amount determined". The same section of the 2017 Act conformed other provisions, rewriting "for '1992' in subparagraph (B)" as "for '2016' in subparagraph (A)(ii)" in §1(i), §59(j) and elsewhere. Section 877(a)(2) was not among them. The threshold still matters: §877A(g)(1)(A) defines a "covered expatriate" through §877(a)(2), and the IRS publishes the indexed amount, $211,000 for 2026 (Rev. Proc. 2025-32, §4.37), which is what the sentence gives when read as it was written in 2004. Part 1 set that reading beside the literal one.
What the Code's editors can do, and what they cannot
The Office of the Law Revision Counsel of the House of Representatives prepares and publishes the United States Code. Its guide to the Code is explicit about the limit: "Errors in spelling, grammar, and punctuation in the original act are not editorially corrected in the Code." A provision enacted with misspelled words or faulty punctuation "is put into the Code exactly as it was enacted, with a footnote inserted as needed to indicate the probable error." For a reference, the instrument is a footnote, "See References in Text note below", and the note itself; the footnote, in the guide's words, "serves to point out an erroneous or misleading reference not discernible from the reference itself."
The Code already shows what this looks like one section away from the five. Section 55(c)(1) refers to "section 27(a)"; §27 lost its subsection (a) designation in 2018. The text keeps "27(a)", a footnote marks it, and the note explains that §27 "as so amended, no longer contains a subsec. (a) designation" and that its text "is identical to that of former section 27(a)". Section 642(b)(2)(C) itself carries one: the reference in clause (i)(I) to §68(b)(1)(C), broken when P.L. 119-21 rewrote §68 in July 2025, already has a References in Text note. The reference two clauses down, broken since 2017, had none.
Changing the words, "(b)(1)(B)(ii)" for "(b)(2)(B)(ii)", takes an Act of Congress, usually a technical corrections bill. Whether one is wanted is for the tax-writing committees. The five entries are small, and in each the intended target is clear from the history. The note is what makes it clear without the history.
How we found them
While applying the amending instructions of P.L. 119-21 to the 58 sections of Title 26 that carry inflation-indexed amounts, we resolved every internal cross-reference in those sections against the consolidated text: each "subsection (x)(y)" or "subparagraph (B)(i)" was looked up at the place it names. The references that did not resolve were read by hand, with the Code's amendment notes, to find when and by which Act the target had moved. Six references did not match what they name. One, §55(c)(1), already carried the Office's note; five did not, and those five went to the Office with our first note on the Act.
At Arxo Law we build executable models of legal texts, and a model has to resolve every reference it executes. A reference that resolves to nothing is a finding, not an exception to skip. The check is a check of text against text: it establishes that a reference does not match its target, and it finds nothing in sections it did not cover. This pass covered 58 sections.
Check it yourself
Two minutes per reference. Open the section on uscode.house.gov or in the Cornell LII copy (§42, §642, §877, §1), find the reference, then look for its target. For the history, scroll to the Amendments notes: under §42, the 2008 entries for "Subsec. (b)" and "Subsec. (d)(2)(D)" and the 1988 entry for "Subsec. (j)(5)(B)"; under §1, the 2017 entry for "Subsec. (f)(3)", which quotes the former text, "(B) the CPI for the calendar year 1992." The Acts are on govinfo: P.L. 110-289 (122 Stat. 2879, 2882), P.L. 115-97 (131 Stat. 2059, 2082), P.L. 108-357 (118 Stat. 1569) and P.L. 100-647 (102 Stat. 3644). The Detailed Guide explains the note types; the note under §55 shows the form, and the next release point will carry the five new ones.
What is still open
Our second note, on the drafting of P.L. 119-21 itself, the table in part 2, is with the same Office and with the other offices named there. The notes change no amount and no liability. What changes is that the Code will tell its reader where each of the five references leads.
Rifat Jumagulov, founder, Arxo Law.