Under the UCC, what evidence can explain or supplement a seemingly unambiguous written contract for the sale of goods?

• A. Course of performance, course of dealing, and trade usage.
• B. Parol evidence showing the exact price.
• C. Oral modifications that contradict the writing.
• D. Fraud and duress evidence.

Answer: (A)

In interpreting a written contract for the sale of goods under the UCC, you can rely on course of performance, course of dealing, and trade usage to explain or supplement the terms. These sources reflect how the parties have acted in similar transactions and what is customary in the trade, helping to illuminate what the contract means or to fill gaps without altering the written terms. Course of performance shows how the parties have already acted under this contract, course of dealing looks at their prior similar transactions, and trade usage refers to common industry practices. Together, they provide context that clarifies ambiguous or silent aspects of the agreement.

Parol evidence showing the exact price would typically contradict a clear written price term, and the parol evidence rule limits such contradictions when the writing is unambiguous. Oral modifications that contradict the writing run into the same problem: the written contract governs, and modifications that conflict with it are not effective to change its terms. Evidence of fraud or duress relates to the contract’s validity rather than explaining or supplementing its terms, so it isn’t about interpretation of the written terms.