The last time that the U.S. Supreme Court invalidated a regulation based on nondelegation doctrine was in 1935, for lack of a necessary "intelligible principle" in two statutes. One provided literally no guidance for the exercise of discretion, and the other conferred authority to regulate the entire economy on the basis of no more precise a standard than stimulating the economy by assuring "fair competition." See Panama Refining Co. v. Ryan, 293 U.S. 388 (1935); A. L. A. Schechter Poultry Corp. v. United States, 295 U.S. 495 (1935). See the discussion in Whitman v. Am. Trucking Ass'ns, 531 U.S. 457, 474 (2001).
The first statement of nondelegation doctrine by the Supreme Court was in Field v. Clark, 143 U.S. 649, 692 (1892) ("That Congress cannot delegate legislative power to the President is a principle universally recognized as vital to the integrity and maintenance of the system of government ordained by the Constitution"). A later-reversed decision of a 2-1 panel of the Eighth Circuit held in favor of nondelegation doctrine in order to invalidate a federal statute in South Dakota v. U.S. Dep't of Interior, 69 F.3d 878 (8th Cir. 1995), vacated and remanded, 117 S. Ct. 286 (1996).
For much of American history, the legislative branch was strictly separate from the executive branch. In 1825 in the case of Wayman v. Southard, Chief Justice Marshall noted that "The line has not been exactly drawn which separates those important subjects which must be entirely regulated by the legislature itself from those of less interest in which a general provision may be made and power given to those who are to act under such general provisions to fill up the details. To determine the character of the power given to the courts by the Process Act, we must inquire into its extent. It is expressly extended to those forms and modes of proceeding in suits at common law which were used in the state courts in September, 1789, and were adopted by that act." The important points of the wording include must be entirely regulated by the legislature itself, subjects of less interest, and fill up the details. This affirmed the strict limits of Separation of Powers as they are built into the Constitution.
In Marshall Field and Co. v. Clark, the Supreme Court noted: "That Congress cannot delegate legislative power to the President is a principle universally recognized as vital to the integrity and maintenance of the system of government ordained by the Constitution." This more affirmative language created the notion of a doctrine of nondelegation.
That changed with J. W. Hampton, Jr. & Co. v. United States.