In the 1942 case of Aguilar v. Standard Oil Co. of New Jersey, the U.S Supreme Court ruled in favor of Standard Oil Company. The plaintiff, Aguilar, a seaman on one of Standard Oil's tankers had been injured while working and sued for damages under both negligence and unseaworthiness claims. However, he was unable to provide sufficient evidence that his injury resulted from any negligence or breach of duty by the company or its employees nor could he prove that the vessel was not seaworthy at departure time which is necessary for an unseaworthiness claim to be valid according to maritime law principles. Therefore, due to lack of substantial proof supporting his allegations against Standard Oil Company regarding their supposed liability for his injuries sustained during work aboard their tanker ship; Mr.Aguilar’s lawsuit was dismissed by court ruling it as unfounded.

In the dissenting opinion for Aguilar v. Standard Oil Co. of New Jersey, Justice Frank Murphy argued that the majority's decision was a misinterpretation of the Jones Act and its purpose to protect seamen. He believed that Aguilar should be considered a seaman under this act because he performed work typical of a ship’s crew, even though his employment was not permanent or continuous. Furthermore, he contended that denying protection to workers like Aguilar would undermine maritime safety as it discourages employers from providing safe working conditions if they know their employees cannot sue for injuries sustained on board. Thus, in his view, any worker who performs tasks essential to a vessel's function and is exposed to maritime perils should qualify as a 'seaman' under the Jones Act regardless of their contractual relationship with their employer.