Minnesota Company v. St. Paul Company was a case heard by the United States Supreme Court in 1867. The case involved a dispute between two companies, Minnesota Company and St. Paul Company, over the ownership of a piece of land in Minnesota. Minnesota Company claimed that it had purchased the land from the United States government in 1854, while St. Paul Company argued that it had purchased the land from the same government in 1856. The Supreme Court ultimately sided with Minnesota Company, ruling that the company had acquired the land first and thus had the superior claim to it. The Court reasoned that the United States government had no authority to sell the same piece of land twice, and thus Minnesota Company's purchase was valid. The Court also noted that St. Paul Company had failed to provide any evidence that it had purchased the land from the government, and thus its claim was invalid. The decision in Minnesota Company v. St. Paul Company established the principle that the United States government cannot sell the same piece of land twice, and that the first purchaser has the superior claim to the land. This decision has been cited in numerous subsequent cases involving disputes over land ownership.

In Minnesota Company v. St. Paul Company, the Supreme Court was tasked with determining whether a contract between two companies could be enforced despite being made in violation of state law. The majority opinion held that the contract should not be enforced as it violated public policy and would encourage other parties to enter into similar contracts in disregard for state laws. However, Justice Field dissented from this decision on the grounds that enforcing such contracts is necessary to protect private rights and interests against arbitrary interference by government authorities or individuals acting under their authority. He argued that if courts were allowed to refuse enforcement of valid contracts simply because they violate some statute, then citizens' property rights would become insecure and subject to legislative whim rather than legal protection; thus, he concluded that while statutes may limit certain types of contractual agreements, those which are otherwise legally binding must still be honored by courts regardless of any violations committed against them.