 at 53 n. 21, 54-55). If competition is sufficiently robust, the reduction in the freedom of some consumers or manufacturers does not rise to the level of antitrust concern, as consumers who wish to avoid the strictures of the exclusivity arrangement can do SO simply by shifting their purchases to another provider. 41 Sylvania marked a sea change in competition policy with respect to vertical integration. In subsequent cases, the Supreme Court has shown greater willingness to entertain efficiency justifications for vertical restraints. 42 The Court's willingness in Aspen Skiing to consider possible business justifications for apparently anti- competitive conduct established that efficiencies can justify monopolization (472 U.S. at 609-11). As a result, lower courts applying the essential facilities doctrine have considered whether possible efficiencies might justify a monopolist's unilat- refusal to deal. Section 4.24 of the Department of Justice's nonhorizontal merger guidelines (1984) also explicitly recognizes that vertical mergers that violate the structural preconditions may nonetheless be permitted if they create sufficient efficiencies. Thereafter, antitrust law has become increasingly hospitable to vertical integration and vertical contractual restraints. 44 These theoretical insights are corroborated by the growing empirical literature on vertical restraints. For example, a recent survey of twenty-three empirical studies of vertical integration and vertical restraints conducted by four members of the FTC staff found "a paucity of support for the proposition that vertical restraints/vertical integration are likely to harm consumers." Indeed, only one of the studies under review found that vertical integration was harmful to consumers, and even in that study the welfare losses were found to be "miniscule." In contrast, "a far greater number of studies found that the use of vertical restraints in the particular context studied improved welfare unambiguously" (Cooper et al. 2005, pp. 660- Another recent surv