Buffalo Law Review

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One of the long-accepted axioms of antitrust law is that the competitive danger posed by exclusivity agreements increases as the market share foreclosed by these arrangements increases. The larger the market share foreclosed by an exclusivity agreement, the less likely the arrangement is to be upheld by courts. And exclusivity arrangements foreclosing extremely large market shares are practically never upheld. The business community has responded by forsaking such arrangements (or concealing them). This Article challenges this very intuitive axiom. It shows that due to an unobserved feature of exclusivity, when extremely large market shares are foreclosed, the competitive danger posed by these arrangements decreases. Exclusivity arrangements foreclosing market shares of 85% and higher should be presumed competitively benign, and therefore legal. Several illustrative examples of industries, in which widespread exclusivity should be allowed in contradiction to the current understanding, are provided. The analysis developed in this Article suggests that for decades antitrust law has been decreasing welfare by forcing businesses to steer clear of a welfare-enhancing practice. The Article calls for a change of this paradigm.