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There is an oft-repeated maxim in U.S. antitrust law that a monopolist's conduct must be examined in its totality in order to determine its legality. Judges admonish that plaintiffs "should be given the full benefit of their proof without tightly compartmentalizating the various factual components and wiping the slate clean after scrutiny of each." As the U.S. Court of Appeals for the Seventh Circuit stated in much-quoted language, "It is the mix of various ingredients ... in a monopoly broth that produces the unsavory flavor."' In this article, I examine the use and misuse of monopoly broth theories. Reflecting a certain ambivalence on the topic, I deliberately have chosen an ambiguous title. Does monopoly broth make bad soup because a monopolist's disparate bad acts sometimes combine to threaten competition in a way that would not be apparent if one simply examined each act in isolation? Or are monopoly broth theories the problem? I argue that both of these senses of my title are valid. On the one hand, in a certain class of cases-particularly those where the legality of a defendant's contracts depends on whether they foreclose a substantial share of the relevant market-it is necessary to consider the aggregate effect of defendant's conduct in order to determine legality. In those cases, determining legality on a contract-by-contract or practice-by-practice basis would systematically lead to false negatives. On the other hand, the "monopoly broth" maxim is susceptible to misuse, particularly if applied to species of conduct whose legality depends on a developed conduct-specific test. In such cases, the prima facie legality of the conduct should be determined on a practice-by-practice basis. Any conduct that does not meet the relevant conduct-specific test should not be allowed to count toward liability or any other issue. In particular, plaintiffs should not be allowed to invoke "monopoly broth" rhetoric in order to defeat established legal tests applicable to different kinds of conduct.