Contested Liability Doctrine: Zarin, Section 108, and Form 1099-C

The contested liability doctrine is a court-made rule that lets you avoid paying income tax on the “forgiven” portion of a debt when the debt itself was genuinely in dispute. Normally, if a creditor cancels part of what you owe, federal tax law treats the canceled amount as income under 26 U.S.C. §61(a)(11).¹ The doctrine carves out settlements where the parties never agreed on the number in the first place: paying less than the creditor claimed doesn’t make you wealthier if the claim itself was contested. Two conditions have to be met. You must have disputed the debt in good faith, and the amount owed must not have been fixed before the settlement.

The Logic Behind the Rule

Cancellation of debt income exists because forgiveness of a real obligation increases your net worth. You keep money you otherwise would have paid, and the tax code treats that benefit as income. When the debt was never firmly established, though, settling for a lower figure doesn’t produce a windfall. It just resolves an open question about what you actually owed. The settlement amount becomes the true debt, and paying the true debt in full leaves nothing to tax.

This idea traces to Treasury regulations covering contested liabilities. The regulation at 26 CFR §1.461-2 defines a “contest” as a bona fide dispute over the proper evaluation of the law or facts needed to determine whether a liability exists or how much it is.² Federal courts extended that reasoning to conclude that settling a genuinely disputed debt produces no cancellation of debt income at all.

The Two Requirements

A Good Faith Dispute

You need to show a legitimate disagreement about the debt’s existence or amount. Courts look for a sincere belief that the creditor’s claim was wrong and some objective basis for it. A dispute manufactured to negotiate a lower settlement won’t qualify. The contest has to be real, and it has to predate the settlement.

Filing a lawsuit isn’t required. An affirmative act denying the validity or accuracy of the claimed amount is enough: a written protest with a partial payment, a formal demand for debt validation, or correspondence rejecting the creditor’s figures.² What matters is that the challenge existed before and during the settlement, not that it was invented afterward.

An Unliquidated Debt

This is where most claims succeed or fail. A liquidated debt is one where the dollar amount is fixed and agreed upon. A signed promissory note for $10,000 at a stated interest rate is the textbook example. If a creditor forgives $3,000 of that note, the $3,000 is a clean increase in your net worth, and it’s taxable.

A disputed contractor bill looks different. If a homeowner refuses to pay a $15,000 invoice because of defective work and the parties settle at $8,000, the true amount owed was never established. The $7,000 gap isn’t forgiven debt. It’s the difference between an unverified claim and the actual resolution. The $8,000 becomes the debt, in full.

Timing matters. If you initially dispute a balance but then sign a written acknowledgment agreeing to the full amount, the debt is liquidated from that point on. Any later reduction would be taxable. The window to contest closes the moment you commit in writing to the number.

The Leading Case: Zarin v. Commissioner

The Third Circuit’s 1990 decision in Zarin v. Commissioner is the anchor case. Zarin ran up roughly $3.4 million in gambling markers at a casino, then disputed the enforceability of the debt under New Jersey gaming regulations. He eventually settled for $500,000. The IRS argued the $2.9 million gap was taxable cancellation of debt income. The court disagreed on two grounds: the debt was unenforceable under state law, meaning it didn’t meet the statutory definition of “indebtedness” at all, and the settlement resolved a contested liability by fixing the amount actually owed rather than forgiving anything.³

The reasoning underscores a broader point. When a debt’s enforceability is genuinely in question, the amount is inherently uncertain, not just the obligation. Because the parties assigned a value to the debt far below its face figure through settlement, the $3.4 million was never a real number for tax purposes. The $500,000 payment satisfied the true debt entirely.³

Proving the Dispute in Practice

Whatever the debt, the paper trail is what carries the argument. If you’re dealing with a collection agency, a formal debt validation request under the Fair Debt Collection Practices Act is especially useful. Collectors who buy debts often hold incomplete records, and validation forces them to document what you actually owe. When a collector can’t substantiate the original balance, a settlement at a reduced figure becomes strong evidence that the debt was disputed.

Keep the validation letter, any response or lack of one, the correspondence rejecting the creditor’s numbers, and the final settlement agreement. Save emails, demand letters, and anything that shows the timing of your objections. Auditors want to see that the contest came first and the settlement came second.

Recourse Versus Nonrecourse Debt

The doctrine addresses recourse debt, where you’re personally liable for the full amount. Forgiveness of recourse debt is normally taxable, and that’s where the doctrine does its work. Nonrecourse debt behaves differently. When the creditor’s only remedy is to seize specific collateral, such as a home securing a mortgage, forgiveness doesn’t generate cancellation of debt income at all. The entire nonrecourse amount is treated as proceeds from disposing of the property, which can create capital gain or loss but not ordinary discharge income.⁴ If your debt is nonrecourse, the doctrine is probably beside the point, though the recourse-nonrecourse line isn’t always clear with real estate loans that have been modified.

If the Doctrine Doesn’t Fit: Section 108 Exclusions

Sometimes the debt was liquidated or the dispute won’t hold up. Section 108 of the Internal Revenue Code offers several ways to exclude canceled debt from income even when the doctrine doesn’t apply.⁵

Insolvency

You qualify if your total liabilities exceeded the fair market value of your assets immediately before the discharge. The exclusion is capped at the amount of insolvency. If your liabilities exceeded your assets by $30,000 and a creditor forgave $50,000, you can exclude $30,000 and must include $20,000 as income.⁶ Many people settling debts for less than the full balance meet this test by definition.

Bankruptcy

Debt discharged in a Title 11 bankruptcy case is fully excluded, with no cap based on assets and liabilities. The discharge must be ordered or approved by the bankruptcy court.⁶

Purchase Price Adjustment

Under Section 108(e)(5), a seller’s reduction of what you owe on a purchase, outside bankruptcy and insolvency, is treated as a decrease in the purchase price rather than forgiven debt. This often applies when a buyer disputes the value or condition of goods and the seller lowers the balance. The effect is a reduced cost basis in the property, not current income.⁷

The Catch

Insolvency and bankruptcy exclusions come with a price. You must reduce certain tax attributes, such as net operating losses, capital loss carryovers, and property basis, in exchange for the exclusion.⁶ The contested liability doctrine has no such tradeoff, which is why it’s the better outcome when it’s available.

How to Report It on Your Return

Getting the tax treatment right requires forms that tell the IRS exactly why the amount on the 1099-C isn’t in your income. Skip the paperwork and the IRS’s automated matching will flag the discrepancy and send you a bill.

Read the Form 1099-C Carefully

Creditors file Form 1099-C when they cancel $600 or more of debt. Check Box 2 for the amount discharged and Box 6 for the identifiable event code. Code G means the creditor decided to stop collection activity, which is not the same as agreeing the debt was undisputed.⁸ If Box 2 reflects the creditor’s original claim rather than what you actually settled, that discrepancy is part of your story.

File Form 8275

Form 8275, Disclosure Statement, is how you disclose a contested liability position. The IRS instructions are explicit that attaching a letter or PDF to your return is not adequate disclosure; the position has to be reported on Form 8275 itself.⁹ Describe the nature of the dispute (breach of contract, billing error, enforceability challenge), the timeline showing when you contested the debt, and why the doctrine applies. If your position challenges a Treasury regulation rather than applies a judicial doctrine, Form 8275-R is the right form instead.¹⁰

Form 982 for Section 108 Exclusions

If you’re relying on insolvency, bankruptcy, or a purchase price adjustment (whether alone or alongside the doctrine), file Form 982. Check the applicable box on line 1, enter the excluded amount on line 2, and complete Part II for attribute reductions.⁶ If you were insolvent, calculate the gap between liabilities and asset values as of the moment before discharge, and hold the underlying records: bank statements, mortgage balances, credit card statements, property valuations.

Hold the Documents

Keep the validation letters, protests, correspondence, and settlement agreement for at least six years after filing. The IRS has an extended assessment window when gross income is understated by more than 25%.¹¹

If the IRS Pushes Back

Even with proper disclosure, the IRS may challenge the position. Knowing the timeline keeps a dispute manageable.

How Long the IRS Has

The IRS generally has three years from the filing date to assess additional tax. That extends to six years if you omitted more than 25% of gross income, a threshold large debt settlements can trip.¹² A fraudulent return carries no time limit.¹¹

Accuracy-Related Penalties

If the IRS decides the position was wrong, Section 6662 imposes a 20% penalty on the underpayment of tax, not on the debt itself.¹³ If excluding $50,000 saved you $11,000 in tax, the penalty would run roughly $2,200 on top of that $11,000. You can avoid the penalty by showing “reasonable cause and good faith.” Reliance on professional tax advice counts, provided the advisor had the relevant facts and the advice wasn’t built on unreasonable assumptions.¹⁴ Filing Form 8275 with proper disclosure also helps demonstrate good faith even if the IRS disagrees on the merits.

Appeals and Tax Court

A letter proposing additional tax generally gives you 30 days to request review by the IRS Independent Office of Appeals. Send the written protest to the IRS address on the letter, not directly to Appeals. If the disputed amount for each tax period is $25,000 or less, you can use the Small Case Request process on Form 12203 instead of a formal protest.¹⁵ Appeals officers have settlement authority and often resolve these cases without litigation when the documentation is clean.

If Appeals doesn’t resolve it, the IRS issues a notice of deficiency, sometimes called a 90-day letter. You have 90 days from the mailing date (150 if you’re outside the United States) to file a petition in Tax Court without paying the tax first. Miss the window and you’d have to pay and sue for a refund in federal district court or the Court of Federal Claims. For deficiencies of $50,000 or less per year, Tax Court’s simplified S Case procedure is available, though S Case decisions can’t be appealed by either side.¹⁶

What the Doctrine Won’t Cover: Student Loans

The temporary federal exclusion for forgiven student loans expired on December 31, 2025. Starting in 2026, balances discharged under income-driven repayment plans are generally taxable as cancellation of debt income. The contested liability doctrine won’t help. Borrowers signed promissory notes for specific amounts, making these debts both liquidated and undisputed. Public Service Loan Forgiveness, Teacher Loan Forgiveness, and discharges due to death or total permanent disability remain tax-free.¹⁷ For a taxable discharge outside those programs, the insolvency exclusion on Form 982 is often the most workable fallback.

1
Office of the Law Revision Counsel. 26 USC 61 – Gross Income Defined
2
eCFR. 26 CFR 1.461-2 – Contested Liabilities
3
Justia. Zarin v Commissioner of Internal Revenue, 916 F2d 110 (3d Cir 1990)
4
Internal Revenue Service. Topic No 431, Canceled Debt – Is It Taxable or Not
5
Office of the Law Revision Counsel. 26 USC 108 – Income From Discharge of Indebtedness
6
Internal Revenue Service. Instructions for Form 982
7
Internal Revenue Service. INFO 2010-0141
8
Internal Revenue Service. Instructions for Forms 1099-A and 1099-C
9
Internal Revenue Service. Instructions for Form 8275
10
Internal Revenue Service. Instructions for Form 8275-R, Regulation Disclosure Statement
11
Internal Revenue Service. Time IRS Can Assess Tax
12
Office of the Law Revision Counsel. 26 USC 6501 – Limitations on Assessment and Collection
13
Office of the Law Revision Counsel. 26 USC 6662 – Imposition of Accuracy-Related Penalty on Underpayments
14
eCFR. 26 CFR 1.6664-4 – Reasonable Cause and Good Faith Exception to Section 6662 Penalties
15
Internal Revenue Service. Preparing a Request for Appeals
16
United States Tax Court. Case Procedure Information
17
Taxpayer Advocate Service. What to Know About Student Loan Forgiveness and Your Taxes