In the case of William H. Seymour and Dayton S. Morgan v Cyrus H. McCormick, the plaintiffs argued that McCormick had infringed upon their patent for a reaping machine by manufacturing a similar device without permission or payment to them for use of their invention. The Supreme Court ultimately ruled in favor of McCormick, finding that his design was distinct from Seymour and Morgan's patented invention due to its different construction and operation; thus he did not violate any patent laws with his own version of the reaping machine. This decision set an important precedent regarding patents as it established that two machines could be considered substantially similar yet still remain distinct enough to avoid infringing on existing patents if they operated differently or were constructed differently from one another.

In the case of William H. Seymour and Dayton S. Morgan v Cyrus H. McCormick, the dissenting opinion was that a patent for an invention should not be considered invalid simply because it has been improved upon by another inventor or manufacturer in some way since its original conception. The dissent argued that such improvements are often necessary to make inventions more useful and practical, and thus should not be seen as infringing on any existing patents held by other inventors or manufacturers who may have made similar inventions prior to those making subsequent improvements. Furthermore, they argued that if these subsequent improvements were deemed invalid due to their similarity with earlier inventions then this would stifle innovation and progress within the industry as inventors would no longer feel encouraged to improve upon existing designs out of fear of legal repercussions from holding companies or individuals who had previously patented similar ideas before them.