Shares held by three large processing firms of open-interest futures positions in soybeans, soybean meal, and soybean oil varied substantially among commodities and individual contract months during 11)57-66. Concentration was frequently higher in soybean meal tllan in soybean oil, and lowest in soybeans. Higher levels of concentration appeared more often In futures contracts 1 to 3 months before the delivery month than in more distant months. Net long, or speculative, positions of the three firms tended to increase as changes in selected futures price relationships increased prospects for priee gains on the unhedged positions.