In the case of MacGregor v. Westinghouse Electric & Manufacturing Co., 1945, the United States Supreme Court ruled in favor of Westinghouse Electric & Manufacturing Co. The dispute arose when MacGregor claimed that he had been wrongfully dismissed from his position at Westinghouse and sought compensation for lost wages and benefits. He argued that his dismissal was a breach of contract by the company. However, the court found no evidence to support this claim as there was no written or verbal agreement specifying a fixed term for employment between MacGregor and Westinghouse. Therefore, it concluded that either party could terminate their relationship at any time without being liable for damages unless there were statutory restrictions or contractual obligations preventing such termination.

In the dissenting opinion for MacGregor v. Westinghouse Electric & Manufacturing Co., it was argued that the majority's decision to uphold a patent on an invention that had already been in public use contradicted established legal principles. The dissent contended that, under U.S law, an inventor loses their right to a patent if they do not apply within one year of the invention being publicly used or sold. In this case, evidence indicated that MacGregor's device had been in public use more than two years before he applied for his patent - thus invalidating his claim according to these standards. Furthermore, it was pointed out that there were no extraordinary circumstances justifying departure from this rule and therefore concluded by stating its disagreement with the court’s ruling.