Potter Stewart

“ Whether the respondents engaged in price discrimination 'where the effect of such discrimination may be substantially to lessen competition or tend to create a monopoly in any line of commerce, or to injure, destroy, or prevent competition with any person who either grants or knowingly receives the benefit of such discrimination * * *.' [1] Phrased more simply, did the respondents' actions have the anticompetitive effect required by the statute as an element of a cause of action? ”

“ The Court's own description of the Salt Lake City frozen pie market from 1958 through 1961, shows that the answer to that question must be no. [2] In 1958 Utah Pie had a quasi-monopolistic 66.5% of the market. ”