Durant v. Essex Company was a United States Supreme Court case that was decided in 1868. The case involved a dispute between the plaintiff, Durant, and the defendant, Essex Company, over a contract for the sale of a steamboat. Durant had agreed to purchase the steamboat from Essex Company for $2,000, but the company refused to deliver the boat after Durant had paid the full amount. Durant then sued Essex Company for breach of contract. The Supreme Court held that the contract was valid and enforceable, and that Essex Company was liable for damages. The Court also held that the damages should be calculated based on the difference between the value of the steamboat at the time of the breach and the amount that Durant had paid for it. The Court's decision in Durant v. Essex Company established the principle that a party who breaches a contract is liable for damages based on the difference between the value of the goods or services at the time of the breach and the amount that the other party paid for them. This principle is still applied in contract law today.

In the case of Durant v. Essex Company, Justice Field delivered a dissenting opinion in which he argued that the majority's decision was contrary to both law and equity. He noted that under established legal principles, when a contract is made for an indefinite period of time it can be terminated by either party at any time with reasonable notice. In this particular case, however, the majority had held that because there was no specific provision in the contract regarding termination or notice requirements, then neither party could terminate without cause and without liability for damages resulting from such termination. This interpretation ran counter to existing law as well as basic notions of fairness; if one party were allowed to unilaterally terminate such contracts without providing reasonable notice or paying damages then they would have too much power over their counterparties and could effectively force them into unfavorable agreements through fear of sudden termination. Therefore Justice Field concluded that while parties should not be able to enter into contracts with impunity they also should not be subject to arbitrary terminations by their counterparts unless agreed upon beforehand in writing