The Guido case in 1899 involved a dispute over the seizure of an Italian vessel, The Guido, by U.S. authorities off the coast of Alaska. The ship was seized for alleged illegal fur seal hunting in Bering Sea, which violated an existing treaty between Great Britain and the United States that prohibited such activities. However, Italy had not been a party to this treaty and thus argued that its vessels were not bound by it. In response to these arguments, the Supreme Court held that while Italy was indeed not part of said treaty, international law still recognized certain areas as common property where no nation could claim exclusive rights or jurisdiction unless expressly agreed upon by all nations concerned - including Bering Sea's fur seals' preservation efforts due to their economic importance at that time. Therefore, even though there wasn't any specific agreement with Italy regarding this matter per se; they were still expected to respect these general principles under customary international law norms.

In the dissenting opinion for The Guido case, it was argued that the majority's decision to uphold a lower court ruling - which found in favor of an insurance company refusing to pay out on a policy due to alleged fraud by the insured party - was incorrect. The dissenting justices believed that there were significant factual disputes about whether or not fraud had actually occurred and felt these should have been resolved through a jury trial rather than summary judgment. They also disagreed with the majority's interpretation of relevant maritime law, arguing it unfairly favored insurers over ship owners. Furthermore, they contended that even if fraudulent intent could be proven, this should not automatically void an insurance contract as long as no actual harm came to the insurer as a result.