In the case of Panama Canal Co. v. Grace Line, Inc., et al., 1957, the Supreme Court ruled in favor of Grace Line and other shipping companies that had been charged additional fees by the Panama Canal Company for their refrigerated cargo ships passing through the canal. The dispute arose when these charges were increased without any changes to services provided or facilities used by these vessels during transit. The court held that under Section 411 of Title II of an Act passed in September 1950, it was unlawful for tolls to be levied on a vessel's capacity beyond what is necessary for its actual transit through the canal unless there are corresponding benefits rendered or facilities furnished specifically related to such excess capacity. As no such benefits or facilities were provided to refrigerated vessels with respect to their extra tonnage (cargo), they could not be lawfully charged more than non-refrigerated vessels carrying similar weight loads.

The dissenting opinion in the Panama Canal Co. v. Grace Line, Inc., et al case argued that the majority's decision was inconsistent with both legislative intent and previous court rulings regarding toll rates for the Panama Canal. The dissenters believed that Congress intended to give discretion to the company running the canal in setting these rates, as long as they were fair and equitable. They also pointed out that prior cases had upheld this interpretation of congressional intent. Furthermore, they disagreed with how the majority interpreted "net investment" in determining what constituted a reasonable rate of return for operating companies, arguing it should include all assets used by an enterprise rather than just those directly involved in providing services or goods.