ding to the Court, the fact that Ski Co. was willing to terminate unilaterally "a voluntary (and thus presumably profitable) course of dealing suggested a willingness to forsake short-term profits to achieve an anticompetitive end," as did the fact that Ski Co. was unwilling to renew the all-Aspen ticket even if compensated at full retail price. Verizon, in contrast, had never dealt with its rivals voluntarily, but instead did SO only under regulatory compulsion at regulated, wholesale prices. In the absence of a preexisting relationship, Verizon's actions did not reveal any "anticompetitive bent." The Court also distinguished Otter Tail as a case in which the network owner "was already in the business of providing a service to certain customers and refused to provide the same service to certain other customers." This fact rendered Otter Tail inapposite, as Verizon had never publicly marketed wholesale access to the OSS at issue in Trinko in the absence of regulation (540 U.S. at 408, 409-10 (internal quotation marks omitted)). These distinctions represent sharp limitations on the scope of liability for a network's unilateral refusal to deal. They clearly suggest that liability will not lie in the absence of a preexisting joint venture or a demonstrated willingness to offer the service to others at a full retail price, because Trinko regarded the willingness to sacrifice profits as a key indicator that the conduct in Aspen Skiing was anticompetitive. Some commentators have argued that the presence of a preexisting course of dealing reveals little, if anything, about a practice's likely competitive impact and that attaching significance to the abandonment of an initial willingness to deal ignores the fact that circumstances change88 and risks discouraging firms from dealing in the first place. 89 Others have suggested that a preexisting willingness to deal provides at least some evidence that the joint venture was efficient.90 There is also language in the opinion that appears to recognize the structural precondit