[1][2] The unanimous Supreme Court agreed with the 10th Circuit that terminating a pro-consumer joint venture without a legitimate business justification could constitute illegal monopolization.

[4][5][6] In a subsequent case, Verizon Communications Inc. v. Law Offices of Curtis V. Trinko, LLP, Justice Scalia, writing for the majority, stated that Aspen Skiing is "at or near the outer boundary of § 2 liability.

[13] It also refused to accept vouchers backed by local banks for the full cash-value of retail price lift tickets.

[16] The District Court awarded Highlands $7,500,000 in treble damages, costs, attorneys' fees and issued a temporary injunction requiring revival of the All-Aspen ticket.

[19][20] The Supreme Court granted cert and affirmed the 10th Circuit's decision based on anticompetitive intent, without analyzing the essential facilities doctrine.

[21] The Supreme Court held that Ski Co.'s refusal to deal with Highlands, despite the historical success of their joint-venture, could constitute illegal monopolization because it deprived consumers of a superior All-Aspen ticket option,[22] injured Highlands' ability to offer competitive multi-area tickets,[23] and, "perhaps most significant," it lacked any efficiency justification.

[26] Ski Co. further argued that it refused to accept Highland's "Adventure-Pack" coupons, even though they were redeemable for cash at local banks, because were cumbersome to process.

"[29] Rejecting all proffered justifications, the Court found that Ski Co. sacrificed short-term profits from selling Highlands lift tickets at retail prices in the hope of long-term anticompetitive gains from injuring their rival.

In its caution to avoid imposing inappropriate duties to deal, the Court focused significant attention on the history of successful joint-ventures to illustrate that such conduct was possible and beneficial.

The 10th Circuit refused to hear Ski Co.'s appeal of the relevant market instruction because they failed to properly object during the trial.

[38] Ski Co. argued that the relevant market should be decided by the judge as a matter of law (applying the Small, but Significant and Non-Transitory Increase in Price or SSNIP test), not the jury.

[46] In fact, in 1975, when Highlands and Ski Co. were cooperating to offer the All-Aspen ticket, the Colorado Attorney General sued both of them for alleged price-fixing.

[47] As the Supreme Court stated in Verizon Communications v. Law Offices of Curtis V. Trinko, Aspen is "[t]he leading case imposing § 2 liability for refusal to deal with competitors.

"[48] Aspen "is at or near the outer boundary of § 2 liability" and represents a "limited exception" to a firm's right to choose with whom to do business that applies when a monopolist is willing to "forsake short-term profits to achieve an anticompetitive end.