Unilateral mistake is generally not a basis for reformation or rescission unless there is

• A. Fraud
• B. Duress
• C. Both Fraud and Duress
• D. Fraud, Duress, or similar inequitable conduct

Answer: (D)

When one party is mistaken about a contract term, a remedy like reformation or rescission isn’t available just for the unilateral error. Relief is possible, however, if the other party engaged in fraud, duress, or similar inequitable conduct. Fraud or duress vitiates genuine consent, so enforcing the contract as written would be unjust; reformation can adjust the document to reflect the true agreement, or rescission can unwind it. The phrase “or similar inequitable conduct” broadens this protection to include other deceitful or coercive actions, such as misrepresentation, concealment, or taking unfair advantage of the mistake. That breadth is why the option describing fraud, duress, or similar inequitable conduct is the best answer.