Article:
Richard S. Markovits, Tie-Ins and Reciprocity: A Functional, Legal, and Policy Analysis, 58 Texas L. Rev. 1363 (1980).
 

Abstract:
A tie-in is a contract in which a buyer and seller of a product agree to act in the same capacities with regard to a second product. Tie-ins involving patented products have been held per se illegal on the basis that the function is to permit sellers to exercise monopolistic leverage that results in economic harm to the competition. Courts have progressively extended this leverage theory to other contexts. Reciprocity is the practice of two firms conditioning their relations with regard to one product on their buyer and seller roles being in another transaction involving another good.

This Article outlines various non-leverage functions that tie-ins and reciprocal trading agreements can perform. It then investigates the competitive impact and legality of such agreements. The Article then analyzes the allocative efficiency and desirability of these agreements.