"For products to be treated as distinct, the tied product must, at a minimum, be one that some consumers might wish to purchase separately without also purchasing the tying product. When the tied product has no use other than in conjunction with the tying product, a seller of the tying product can acquire no additional market power by selling the two products together. If sugar is useless to consumers except when used with flour, the flour seller's market power is projected into the sugar market whether or not the two products are actually sold together; the flour seller can exploit what market power it has over flour with or without the tie. The flour seller will therefore have little incentive to monopolize the sugar market unless it can produce and distribute sugar more cheaply than other sugar sellers. And in this unusual case, where flour is monopolized and sugar is useful only when used with flour, consumers will suffer no further economic injury by the monopolization of the sugar market." [Justice O'Connor, Jefferson Parish Hospital District v. Hyde, 466 U.S. 2 (1984)].