An agreement requiring the tie-in of the purchase of one product in connection with the contract for another product.  Many tying arrangements are illegal under the antitrust laws.

Reference Desk:

A tying arrangement is ‘an agreement by a party to sell one product but only on the condition that the buyer also purchases a different (or tied) product, or at least agrees that he will not purchase that product from any other supplier.’ Such an arrangement violates § 1 of the Sherman Act if the seller has ‘appreciable economic power’ in the tying product market and if the arrangement affects a substantial volume of commerce in the tied market.

Eastman Kodak Co. v. Image Technical Services, Inc., 504 U.S. 451, 461-462 (1992).

A tying arrangement is ‘an agreement by a party to sell one product but only on the condition that the buyer also purchases a different (or tied) product.’  The law of tying requires proof of five specific elements: first, a tying and a tied product; second, evidence of actual coercion by the seller that in fact forced the buyer to accept the tied product; third, sufficient economic power in the tying product market to coerce purchaser acceptance of the tied product; fourth, anticompetitive effects in the tied market; and fifth, involvement of a ‘not insubstantial’ amount of interstate commerce in the tied product market.

Yentsch v. Texaco, Inc., 630 F.2d 46, 56-57 (2d Cir. 1980).

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