We will not summarize the discussion of general antitrust rules and principles available in existing treatises. Rather, we will focus on some ways in which regulation affects the application of antitrust law. The Way Antitrust Rules Are Applied. Regulatory policy must be weighed in deciding whether particular conduct violates the Sherman Act.
Regulation can even affect the application of per se rules.
The Court did not apply a per se rule in this regulated context. In An Antitrust Context. The shift from a traditionally regulated industry to a competitive marketplace brings with it the potential for antitrust violations. It is precisely at such a stage, when a monopolist confronts competition in a market for the first time, that the potential for competitive abuse is at its greatest. In this context, violation of a rule or tariff imposed by the regulator can provide the evidence of anticompetitive or predatory conduct necessary to establish an antitrust violation.