The Chicago Board of Trade is being sued in the US District Court in Chicago for a 1989 decision that forced the owners of large amounts of soybean futures contracts to sell their positions.

Farmer Harvey Joe Sanner is alleging that the Board knew its order would cause prices to drop, thereby benefiting the trading firm of one of its directors.

At the time, the Board had claimed that its order was aimed at preventing an Italian firm, Ferruzzi Finanziaria SpA, from cornering the market; it said that it had been aggressively buying futures. Sanner, a former president of the now-defunct American Agriculture Movement, also alleges that the Board caved into pressure from food processor Cargill Inc, a large soybean customer which needed a lower price to buy back contracts.