In the case of A.B. Kirschbaum Co. v. Walling, the U.S Supreme Court was tasked with determining whether employees who worked in a loft building that housed various manufacturing operations could be classified as engaged in commerce or production of goods for commerce under the Fair Labor Standards Act (FLSA). The petitioner, A.B. Kirschbaum Co., owned and operated this building where tenants produced clothing items which were then shipped across state lines; however, they argued their maintenance staff did not directly engage in interstate commerce and thus should not fall under FLSA's jurisdiction. The court ruled against Kirschbaum Co., stating that even though these employees weren't directly involved in producing goods for interstate commerce, their work was essential to the overall operation which did involve such production - hence they fell within FLSA's purview. This decision expanded interpretations of what constituted engagement 'in' or 'closely related and directly essential' to commercial activity covered by federal labor laws.

The dissenting opinion in the case of A. B. Kirschbaum Co. v Walling argued that the majority's decision to classify maintenance and custodial workers as engaged in commerce, thus subject to federal wage regulations, was an overreach of authority by Congress under the Commerce Clause. The dissent contended that these employees were not directly involved in interstate commerce but rather provided services incidental to it; therefore, they should be outside the scope of federal regulation according to previous court decisions and interpretations of the Fair Labor Standards Act (FLSA). They further expressed concern about potential implications for states' rights and feared this ruling could lead to excessive interference from federal authorities into local matters traditionally governed by state law.