type
sm-banner
background-image
background-image-mobile
background-color
navy
eyebrow
Tax alert
title

Tax Court warns 70/30 basket swaps may not protect tax benefits

subtitle
Ruling in SIH Partners shows technical compliance may not defeat anti-abuse rules
date
October 09, 2026
text-color
light
gradient-overlay
dark
breadcrumb

Home

Insights

Tax regulatory resources

2026

  • Federal tax
  • Income & franchise tax
  • Tax controversy
  • Private client services
  • Financial services
  • Asset management

Executive summary: Tax Court ruling on basket swaps signals greater focus on economic substance, tax results

In SIH Partners LLLP v. Commissioner, the Tax Court held that satisfying a technical regulatory threshold did not prevent the IRS from challenging tax benefits arising from a basket swap. Although the taxpayer complied with a regulatory mechanical overlap test, the court concluded that the investment strategy was subject to an anti-abuse rule because it generated tax benefits that significantly exceeded its expected pretax economic return.

The decision reflects a broader willingness by the IRS and the courts to evaluate the economics and purpose of investment-fund transactions rather than focus exclusively on technical compliance with regulatory requirements. Recent IRS guidance addressing other tax-driven investment strategies points in the same direction.

Investors and fund managers using basket swaps, portfolio hedges and similar arrangements may benefit from reassessing whether the transaction's economics, risk profile and business purpose support the intended tax treatment. Documentation, contemporaneous analysis and a clear understanding of the transaction as a whole may become increasingly important as IRS scrutiny of investment-fund strategies continues to evolve.

Tax Court denies tax benefits for investor using basket swap

A 70/30 basket swap is designed to hedge an investor’s stock position to reduce risk while keeping the overlap between swapped holdings below a 70% regulatory threshold to qualify for favorable tax treatment. In SIH Partners LLLP v. Commissioner, 167 T.C. No. 8 (2026), the taxpayer stayed below that mechanical threshold, but the Tax Court still denied qualified-dividend treatment for more than $170 million of dividend income and reduced foreign tax credits (FTCs) by more than $25 million under the regulation’s anti-abuse rule. The court determined that despite meeting the regulations’ mathematical test, the taxpayer’s transaction was still subject to anti-abuse rules because of its economic substance and because it produced tax savings that significantly exceeded expected pretax profit.

What is a 70/30 basket swap?

A basket swap is a derivative tied to a group of stocks rather than a single stock. Under the section 246 regulations, a position tied to a portfolio of at least 20 unrelated issuers generally is treated as substantially similar or related property (SSRP) when it substantially overlaps the investor’s own holdings. The overlap is substantial when it reaches 70% or more. That threshold gives the strategy its name; the basket swap is structured so that less than 70% overlaps the investor’s stocks and more than 30% reflects other stocks or market indices.

The intended result is that the investor keeps the stock but uses the swap to reduce downside risk. Tax benefits related to stock ownership are intended to remain unimpeded by the swap.

Intended tax benefits of the 70/30 basket

To qualify for tax benefits related to stock ownership, several tax rules require the investor to retain meaningful market risk. The principal benefits at issue in SIH Partners were:

  • Qualified dividend income (QDI): Non-corporate taxpayers may pay tax on qualified dividends at lower capital gain rates, but only if the applicable holding period requirement is met.
  • Foreign tax credits (FTCs): Foreign withholding tax on dividends may generate a credit, but the recipient must satisfy a holding-period requirement.

The applicable holding period rules generally disregard days on which the taxpayer’s risk of loss is reduced by a position in SSRP.

Therefore, the appeal of a 70/30 basket is that it appears to reduce risk without crossing a bright-line threshold. However, the Tax Court’s decision makes clear that a strategy designed around the threshold may still fail if the overall economics trigger the anti-abuse rule.

The mechanical test and the anti-abuse rule

For a qualifying portfolio, the mechanical test generally looks to whether 70% or more of the position overlaps the taxpayer’s stockholdings. A basket below that threshold generally is tested as one instrument rather than as a collection of single-stock hedges, and therefore is not SSRP. But the regulations also contain an anti-abuse rule that can treat the position as SSRP even when the mechanical threshold is not met. See Reg. section 1.246-5(c)(1)(iii), (vi).

The anti-abuse rule focuses on the substance of the position and the purpose of the plan. It can apply when:

  • Changes in the position, or in the stocks it reflects, are reasonably expected to track—directly or inversely—all or part of the taxpayer’s stockholdings.
  • The position is part of a plan whose principal purpose is to obtain tax savings that significantly exceed the expected pretax economic profit.
The SIH Partners basket swap

SIH Partners purchased stock in four Swiss companies—Nestlé, Novartis, Roche and Swisscom—and entered into a portfolio swap with Morgan Stanley. The swap created identical short exposure to those four stocks, plus short exposure to market indices intended to provide broader downside protection. SIH Partners received dividends on the Swiss stocks and made substitute-dividend payments to Morgan Stanley under the swap.

For 2012, SIH Partners reported more than $170 million of dividend income as QDI and claimed FTCs exceeding $25 million. The IRS challenged both benefits.

Why the Tax Court denied the benefits

The taxpayer won on the first issue, the mathematical 70% test. On the relevant 2012 testing date, the overlap was about 64%, so the swap passed the regulation’s mechanical 70% substantial-overlap test.

The court also refused to split the basket into separate swaps under substance-over-form principles as the IRS had requested, ruling that the nonoverlapping portion had a real business purpose because it provided protection against a broader market decline.

But the taxpayer lost under the anti-abuse rule. Rather than compare the swap as a whole with the stocks generating dividends, the court focused on the short positions tied to the four Swiss stocks. Those positions were an exact inverse of the taxpayer’s long positions—a “100 percent hedge,” in the court’s words—and were reasonably expected to track them.

The court also found that the expected tax savings significantly exceeded the expected pretax economic profit.

After considering pre- and post-transaction analyses of the transaction's expected returns and costs, the court concluded that the expected pretax result ranged from a loss to a profit of about $2.4 million, compared with anticipated tax savings of roughly $25 million.

The SIH Partners decision fits a broader IRS enforcement focus

SIH Partners also arrives during a period of increased IRS attention to tax-driven investment-fund strategies. Within two months of the decision, the IRS issued Notice 2026-62 and  Rev. Rul. 2026-20, addressing a purported section 351 exchange involving a newly formed ETF and other tax-advantaged investment-fund strategies. Although those transactions are legally and economically different from a 70/30 basket, the developments reflect a common enforcement theme: The IRS is inclined to examine coordinated transactions as a whole when technical compliance may not align with the arrangement’s overall economics.

What this means for investors

Taxpayers using basket swaps, portfolio hedges or similar derivatives may want to review existing and proposed arrangements before the IRS raises the issue.

For a 70/30 basket, that review should consider how much risk the taxpayer retained, whether components of the hedge are reasonably expected to track the protected holdings and whether the expected tax savings significantly exceed the expected pretax economic profit. Any economic analysis should use supportable assumptions and contemporaneous information. The documentation should address the purpose and economics of the entire arrangement—not simply show that the position remained below a numerical threshold.

How your tax advisor can help

Your tax advisor can help evaluate existing and proposed basket swaps, portfolio hedges and other tax-sensitive investment strategies in light of SIH Partners and the IRS’s broader enforcement focus. That review can include:

Your tax advisor can help evaluate the transaction as a whole—not simply confirm that a numerical threshold has been satisfied—and provide a supportable analysis that reflects both the governing technical rules and the transaction’s actual economics.

Section Title
Section Subtitle
Layout
feature
Pages
  • /insights/services/business-tax/tax-planning-irs-treasury-scrutiny-key-questions
  • /insights/services/business-tax/treasury-scrutiny-tax-investments
Cards per Row
3
Number of Rows
1
Order By
date
Sort Order
descending
Show CTA Button
true
Override CTA Label
Carousel On Mobile
true
Carousel Swiper Text
Link Target
Same Tab