TYING CONTRACT: A type of contract commonly used in the late 1800s and early 1900s in which the sale of one good by a producer was made conditional on the purchase of another good. This was commonly used by firms to extended the market control they had over a product in a monopolized market to another product in a more an otherwise competitive market. The use of tying contracts was specifically outlawed by the Clayton Act in 1914. However, modern firms continue to use tying contracts with varying degrees of success. See also | Clayton Act | monopoly | exclusive agreement | interlocking directorate | antitrust laws | Sherman Act | price discrimination |