In the 1913 case of Nadal v. May, the United States Supreme Court dealt with a dispute over property rights in Puerto Rico. The plaintiff, Nadal, claimed that he had purchased land from its original owner and was therefore entitled to ownership. However, the defendant, May argued that they were granted possession of this land by Spanish law before it became U.S territory following the Spanish-American War in 1898. The court ruled in favor of May stating that under Spanish civil law which was still applicable at that time in Puerto Rico; mere possession could ripen into full ownership if held for an uninterrupted period without any legal challenge from other parties including true owners. Therefore since there was no evidence showing interruption or challenge during their tenure on this property prior to purchase by Nadal; they were deemed rightful owners.

In the dissenting opinion for Nadal v. May, it was argued that the majority's decision to uphold a tax on foreign corporations doing business in Puerto Rico was unjust and inconsistent with previous rulings. The dissenting justices contended that this tax violated the uniformity clause of the U.S Constitution, which requires all duties, imposts and excises to be uniform throughout the United States. They pointed out that Puerto Rico is part of U.S territory and therefore should not be subjected to discriminatory taxation policies different from those applied in other parts of America. Furthermore, they disagreed with majority’s interpretation of Downes v Bidwell case (1901), arguing instead that it established a principle against imposing unequal taxes on American territories like Puerto Rico.