In the United Gas Improvement Co. v. Callery Properties, Inc., case of 1965, the Supreme Court ruled on a dispute over natural gas pricing between producers and pipeline companies. The court held that under Section 4 of the Natural Gas Act (NGA), pipelines could not unilaterally change contract prices by filing for new rates with Federal Power Commission (FPC). Instead, they must seek FPC approval to ensure just and reasonable rates are maintained in public interest. Furthermore, it was decided that if a 'public hearing' clause exists in contracts allowing pipelines to request price changes from FPC without producer's consent, such clauses should be interpreted as permitting only lawful actions consistent with NGA provisions rather than unilateral rate alterations.

In the dissenting opinion for United Gas Improvement Co. et al. v. Callery Properties, Inc., et al., Justice Harlan argued that the Federal Power Commission (FPC) did not have jurisdiction over sales of natural gas made directly to industrial consumers in interstate commerce because such sales were not subject to "resale." He contended that Congress intended for the Natural Gas Act's regulatory scheme to apply only where gas was sold at wholesale, i.e., for resale. The majority’s interpretation would mean an unwarranted expansion of FPC authority into areas traditionally regulated by states and could lead to a dual regulation system which Congress sought to avoid when it enacted the Natural Gas Act. Furthermore, he disagreed with how broadly the court interpreted 'public interest' as used in Section 7(e) of this act; instead suggesting a narrower view focusing on protecting consumers from exploitation by natural gas companies rather than considering national energy policies or conservation measures.