The National Hat Pouncing Machine Company v. Hedden case in 1892 revolved around a dispute over import duties on certain machinery. The National Hat Pouncing Machine Company imported machines designed to finish hats and claimed that these should be classified under the tariff act as "machines for manufacturing," which would subject them to a lower duty rate. However, Edward L. Hedden, the Collector of Customs at the Port of New York, classified them as "brushing, finishing or other like machines" which attracted higher rates of duty according to the Tariff Act of March 3rd, 1883. The Supreme Court ruled in favor of Hedden stating that while these machines were indeed used in manufacturing hats they were not 'manufacturing' machines per se but rather tools used within the process and thus fell into their designated category attracting higher tariffs under existing law.

The dissenting opinion in the case of National Hat Pouncing Machine Company v. Hedden, 1892, argued that the patent at issue was not a new invention but rather an improvement on existing technology and thus should not be granted full patent protection. The justice disagreed with the majority's interpretation of what constitutes a "new" invention under U.S. patent law and believed that granting such broad protections to minor improvements could stifle innovation by preventing others from building upon or improving existing technologies without fear of infringement lawsuits. This view suggests a more restrictive approach to patent eligibility, emphasizing originality over incremental advancements.