Tax Legal Services · Primary-source case analysis

Cottage Savings: Why the Section 165 Loss Ruling Was Narrow

By Aneeta Mishra and Timothy Chan

Published May 14, 2026 · Updated October 20, 2026

Decision: Cottage Sav. Ass’n v. Comm’r, 499 U.S. 554 (1991).

A transaction can clear one tax question and still face another. In Cottage Savings, the Supreme Court first decided whether the mortgage exchange produced a realized loss. It then addressed a separate challenge: Whether that loss was actually sustained under section 165. The second ruling was narrower than a general approval of economically similar asset swaps.

The government raised a separate deduction objection

The Sixth Circuit had accepted realization but disallowed the deduction under section 165. The Commissioner argued that the losses lacked economic substance. The Court read that sparse argument as questioning whether the losses were genuine. This was a different objection from whether the exchanged assets carried different legal rights.

Part III of the Supreme Court opinion, pages 567–568, deals with that deduction argument. Keeping the two questions separate matters: A decision that an exchange realizes a loss does not, by itself, answer every possible objection to deducting it.

The Court distinguished the retained-ownership problem

The Commissioner relied on Higgins v. Smith, involving a taxpayer who sold securities at a loss to his wholly owned corporation. As the Cottage Savings Court explained, the taxpayer there retained the benefit of the securities through that corporation, and the transaction was not at arm’s length—that is, between parties dealing independently.

In Cottage Savings, the government did not contend that the reciprocal transactions lacked arm’s-length dealing or that the thrift retained practical ownership of the participation interests it transferred. The Court therefore found the Higgins comparison unpersuasive.

Why the section 165 ruling was narrow

The Commissioner’s section 165 argument occupied one sentence in a footnote in its brief, without further explanation. After distinguishing Higgins, the Court noted that the Commissioner had advanced no other argument supporting the ruling below and found the losses sustained for purposes of this case. Cottage Savings, 499 U.S. at 567–68.

Read the transaction documents against the actual objection

For a current loss dispute, first identify what the IRS is challenging. Is it the existence of a realization event, whether a loss was genuinely sustained, the amount claimed or a different limitation? Those objections may require different evidence and different authority.

The purchase and participation agreements, ownership rights retained after closing, relationships between the parties, payment records and valuation support can help identify the factual dispute. A label such as “sale” does not answer all of those questions. Nor does similar economic value alone establish the outcome.

Key takeaways

• Part III concerns the separate section 165 objection, not just realization under section 1001.
• The absence of a retained-ownership or arm’s-length dispute was important to the result.
• The Court reversed the Sixth Circuit and remanded; it did not affirm a judgment denying the deduction.
• Treat the current tax year, transaction terms and any additional deduction restrictions as separate questions.

Read the related analysis of Blackmun’s separate disagreement about the mortgage exchange.