In the United States v. Piatt and Salisbury case of 1894, the Supreme Court was tasked with determining whether a land grant issued by Congress to construct railroads in Florida also included ownership rights over phosphate deposits found beneath the surface. The defendants, Piatt and Salisbury, had purchased lands from a railroad company that were originally granted by Congress under an Act passed in 1841 for constructing railroads. They later discovered valuable phosphate deposits on these lands and began mining operations. However, they faced opposition from another party who claimed ownership of these minerals based on a Spanish land grant predating Congressional action. The court ruled against Piatt and Salisbury stating that when Congress made this land grant it did not intend to include mineral rights as well; therefore those remained with their original owners or successors unless explicitly transferred otherwise. This decision established an important precedent regarding property rights associated with public land grants.

In the dissenting opinion for United States v. Piatt and Salisbury, Justice Brewer argued that the majority's decision was based on a misunderstanding of the nature of Spanish land grants in Florida. He contended that under Spanish law, once a grant had been made by an authorized official and possession taken by the grantee, it could not be revoked even if there were irregularities in its issuance. Therefore, he believed that when Spain ceded Florida to the U.S., all such grants became binding on American courts regardless of any subsequent discoveries about their original validity or legality under Spanish law. In his view, this principle should have led to upholding Piatt and Salisbury’s claim to ownership over disputed lands rather than rejecting it as invalid due to alleged fraud committed during its initial granting process.