Realization Survives, but the Door Stays Open: Reading Moore v. United States

What the Court decided

On June 20, 2024, in *Moore v. United States*, the Supreme Court upheld the Mandatory Repatriation Tax (MRT) enacted as part of the Tax Cuts and Jobs Act under IRC § 965. The vote was 7 to 2, with Justice Kavanaugh writing for the majority.

The MRT imposed a one-time tax on a U.S. shareholder's share of a controlled foreign corporation's accumulated post-1986 earnings, whether or not those earnings had ever been distributed. The Moores, who held a roughly 13 percent stake in an Indian company that reinvested its profits and never paid them a dividend, were taxed on their share of those undistributed earnings. They argued the tax was unconstitutional because they had realized no income.

The Court disagreed, but on a deliberately limited theory.

The narrow ground that matters

The majority did not hold that Congress may tax anything it likes. It held something much narrower: Congress may attribute the realized but undistributed income of an entity to that entity's shareholders or partners, and tax them on it. The income at issue had in fact been realized — by the company. The MRT simply attributed the company's realized earnings to its U.S. owners, much as Subpart F, the GILTI regime, and ordinary partnership pass-through taxation have long done.

The Court cabined its holding to that situation: a tax on the shareholders of an entity, on income realized by the entity, attributed to the shareholders, where the entity itself has not been taxed on that income. The long historical pedigree of pass-through and anti-deferral taxation carried the day.

What the Court refused to decide

This is the part that keeps the larger debate alive. The Court expressly declined to decide whether realization is a constitutional prerequisite for an income tax under the Sixteenth Amendment. Because the entity here had realized the income, the Court did not need to reach the harder question of whether Congress may tax genuinely unrealized gains — appreciation in property a taxpayer still holds.

The majority went further and drew explicit boundaries. It said its opinion did not address taxes on holdings, wealth, or net worth, and did not address taxes on appreciation. It also cautioned that nothing in the opinion should be read to authorize taxing both an entity and its owners on the same undistributed income.

Read together with the separate opinions, the signal is unmistakable. Justice Barrett, joined by Justice Alito, concurred only in the judgment and would have been more protective of a realization requirement. Justices Thomas and Gorsuch dissented, arguing the Sixteenth Amendment does require realization and that the MRT was an unapportioned direct tax. The realization question, in other words, has serious support on the Court — it simply was not the question this case forced.

Why this matters for planning, even now

For owners with CFC interests and § 965 exposure, the practical answer is in: the transition tax stands, and protective refund claims premised on its unconstitutionality no longer have a live theory behind them. Anyone who filed such a claim should reassess it in light of the decision.

For the broader policy fights, *Moore* is best read as a narrow win that resolved a specific tax while leaving the constitutional frontier untouched. Proposals to tax unrealized appreciation — billionaire minimum-tax concepts, mark-to-market regimes for the very wealthy — did not get a green light from this decision, and arguably drew a warning. They remain constitutionally untested and, on the strength of the concurrence and dissent, genuinely contested.

The disciplined read is neither relief nor alarm. The existing anti-deferral architecture is secure. The next constitutional battle over what counts as taxable income has been postponed, not won.

Key takeaways

• *Moore v. United States* (June 20, 2024, 7-2) upheld the § 965 transition tax.
• The holding rests on a narrow ground: Congress may attribute an entity's realized, undistributed income to its owners.
• The Court expressly declined to decide whether realization is constitutionally required, and disclaimed any view on wealth or appreciation taxes.
• Wealth-tax and mark-to-market proposals remain untested; the constitutional question survives for another case.

What to do now

1. Reassess any protective § 965 refund claims.

The constitutional theory those claims relied on did not prevail. Evaluate whether to maintain or withdraw them.

2. Treat the anti-deferral regimes as settled.

Subpart F, GILTI, and partnership pass-through taxation sit on firm ground after *Moore*.

3. Do not over-read the result for wealth-tax planning.

The decision did not bless taxing unrealized gains. Planning premised on either certainty here is premature.

Bottom line

*Moore* answered the question in front of it and declined the one behind it. The transition tax holds; the realization debate continues. For owners and advisors, that means closing out the § 965 question while keeping a clear eye on a constitutional fight that is far from over.