The article explores how complementary monopolies should impact antitrust merger policy. The researchers use a strategic model to show that when monopolists with complementary inputs offer supply schedules and engage in bargaining with producers, the outcome is a joint-profit-maximizing equilibrium. This equilibrium leads to output levels similar to those of a bundling monopoly. Contrary to the Cournot effect, where prices are higher than in a bundled monopoly, this model shows that consumers and producers benefit more from supply schedules and bargaining than from fixed prices. This has implications for antitrust policies regarding vertical and conglomerate mergers.