Fourteenth Amendment, Section 1:
All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside. No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any State deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.
On the principle that the law may hit the evil where it is most felt, state antitrust laws applicable to corporations but not to individuals, 1 or to vendors of commodities but not to vendors of labor, 2 have been upheld. Contrary to its earlier view, the Court now holds that an antitrust act that exempts agricultural products in the hands of the producer is valid. 3 Diversity with respect to penalties also has been sustained. Corporations violating the law may be proceeded against by bill in equity, while individuals are indicted and tried. 4 A provision, superimposed upon the general antitrust law, for revocation of the licenses of fire insurance companies that enter into illegal combinations, does not violate the Equal Protection Clause. 5 A grant of monopoly privileges, if otherwise an appropriate exercise of the police power, is immune to attack under that clause. 6 Likewise, enforcement of an unfair sales act, under which merchants are privileged to give trading stamps, worth two and one-half percent of the price, with goods sold at or near statutory cost, while a competing merchant, not issuing stamps, is precluded from making an equivalent price reduction, effects no discrimination. There is a reasonable basis for concluding that destructive, deceptive competition results from selective loss-leader selling whereas such abuses do not attend issuance of trading stamps
across the board, as a discount for payment in cash. 7