The U.S. Supreme Court case NYNEX Corporation, et al. v. Discon, Incorporated (1998) revolved around an antitrust claim brought by Discon against NYNEX and its subsidiaries for alleged price discrimination under the Sherman Act. The court ruled in favor of NYNEX, stating that a plaintiff seeking to establish competitive harm from vertical price discrimination must show that the pricing practices had an actual adverse effect on competition as a whole rather than simply affecting individual competitors like Discon itself. This ruling clarified that antitrust laws are designed to protect competition broadly rather than specific businesses within the market.

The dissenting opinion in the case of NYNEX Corporation v. Discon, Incorporated argued that the majority's decision was too narrow and failed to consider broader antitrust implications. The dissent believed that NYNEX had violated antitrust laws by engaging in a scheme with another company to raise prices for its customers, thereby excluding competitors like Discon from the market. They contended that this conduct constituted an anti-competitive conspiracy under Section 1 of Sherman Act and should be penalized accordingly. Furthermore, they disagreed with the majority's interpretation of Brooke Group Ltd v Brown & Williamson Tobacco Corp., arguing it did not apply because this case involved a conspiracy between two companies rather than unilateral action by one firm. In their view, allowing such behavior would undermine competition law enforcement and harm consumers through higher prices.