the statute in an anticompetitive manner. It should not mean that preemption is impossible whenever both procompetitive and anticompetitive results are conceivable. The per se rule "reflects the judgment that such cases are not sufficiently common or important to justify the time and expense necessary to identify them." Another important, yet, in the context of Rice, ambiguous guideline regarding preemption by Section 1 is the Court's statement that a "state statute is not preempted by the federal antitrust laws simply because the state scheme might have an anticompetitive effect." The meaning of this statement is clarified by examining the three cases cited in Rice to support the statement. In New Motor Vehicle Board v. Orrin W. Fox Co., automobile manufacturers and retail franchisees contended that the Sherman Act preempted a statute requiring manufacturers to secure the permission of a state board before opening a new dealership if and only if a competing dealer protested. They argued that a conflict existed because the statute permitted "auto dealers to invoke state power for the purpose of restraining intrabrand competition." In Exxon Corp. v. Governor of Maryland, oil companies challenged a state statute requiring uniform statewide gasoline prices in situations where the Robinson-Patman Act would permit charging different prices. They reasoned that the Robinson-Patman Act is a qualification of our "more basic national policy favoring free competition" and that any state statute altering "the competitive balance that Congress struck between the Robinson-Patman and Sherman Acts" should be preempted. In both New Motor Vehicle and Exxon, the Court upheld the statutes and rejected the arguments presented as Merely another way of stating that the . . . statute will have an anticompetitive effect. In this sense, there is a conflict between the statute and the central policy of the Sherman Act – 'our charter of economic liberty'. . . . Nevertheless, this sort of conflict cannot itself constitute a sufficient reason for invalidating the . . . statute. For if an adverse effect on competition were, in and of itself, enough to render a state statute invalid, the States' power to engage in economic regulation would be effectively destroyed. This indicates that not every anticompetitive effect warrants preemption. In neither Exxon nor New Motor Vehicle did the created effect constitute an antitrust violation. The Rice guideline therefore indicates that only when the effect unreasonably restrains trade, and is therefore a violation, can preemption occur.