In the fall of 1955, traders Sam Siegel and Vincent Kosuga cornered the onion futures market on the Chicago Mercantile Exchange, eventually controlling 99.3% of the available onions in Chicago. They accumulated short positions while storing over 30 million pounds of onions, then had the stocks reconditioned outside Chicago before repackaging and returning them to flood the market, driving the price of a 50‑pound bag from $2.75 to just 10 cents. This manipulation caused significant losses for onion farmers and prompted a public outcry, leading to congressional action.
The Onion Futures Act was introduced in the House of Representatives as H.R. 376 by Gracie Bowers Pfost on January 3, 1957, passed by the House on March 13, 1958, and by the Senate on July 11, 1958 before being signed into law by President Dwight D. Eisenhower on August 28, 1958. The act prohibited trading futures contracts on onions and, as amended in 2010 by the Dodd‑Frank Wall Street Reform and Consumer Protection Act, also banned futures on motion picture box office receipts. After the ban, the Chicago Mercantile Exchange lost a major trading product, sued unsuccessfully to overturn the prohibition, and later revived its fortunes by introducing futures contracts on pork bellies and frozen concentrated orange juice.
In April 2026, a group of undergraduate students at the University of Chicago formed For Our Futures, an advocacy organization seeking the repeal of the act. On April 17, the group held a demonstration on the university's main quadrangle, distributed approximately 100 raw onions, and collected 131 signatures on a petition supporting repeal. Four members subsequently held a similar demonstration at Northwestern University on May 1, where they reported collecting another 99 signatures. The organizers said that its objective of legalizing onion futures was genuine. The effort has drawn attention from commentators such as Bloomberg Opinion’s Matt Levine, who noted the irony of targeting a law born from a historic market manipulation. Academics remain divided on the effect of onion futures trading on price volatility, with studies offering conflicting conclusions since the 1960s.