Columbia Nitrogen Corp. v. Royster Co.

Columbia Nitrogen (defendant) agreed to buy a minimum quantity of phosphate from Royster (plaintiff) for three years at a set per-ton price, in a contract with a merger clause excluding "verbal understandings"; when phosphate prices dropped sharply, Columbia bought less than the minimum, forcing Royster to sell the surplus at lower prices. Royster sued for damages, and Columbia sought to introduce evidence that the parties routinely deviated from stated contract prices in prior dealings and that industry practice treated price and quantity terms as flexible projections; the district court excluded this evidence, and judgment was entered for Royster.