Justice Cardozo, joined by Justices Brandeis and Stone, concluded that the price provisions validly regulated sales in interstate commerce. Setting prices for interstate sales regulates commerce itself, rather than merely the local conditions preceding or following it. Congress could also reach intrastate sales where their pricing had a close and practical connection to interstate prices.
In Cardozo's view, the coal industry's destructive price competition, overproduction, wage cuts, strikes, and threatened interruptions of supply supplied a rational basis for price regulation consistent with due process. The statute also supplied workable administrative standards, including just and equitable prices, production costs, relative market values, and protection against undue preferences.
He regarded the labor and price sections as severable. The statute expressly said that invalidity of one provision would not affect the remainder; the price and labor rules appeared in separate parts; and key wage-and-hour rules might never take effect unless the required private agreements were reached. Price regulation, by contrast, could operate immediately and independently.
Because valid price provisions were sufficient to support the regulatory penalty, producers had a duty to enter the Code while retaining their statutory right to contest particular provisions later. Cardozo thought any challenge to labor provisions not yet enforced was premature. He would have affirmed the judgments sustaining the Act's operative price-regulation scheme.