The Chicago Board of Trade (CBOT), established on April 3, 1848, is one of the world's oldest futures and options exchanges. On July 12, 2007, the CBOT merged with the Chicago Mercantile Exchange (CME) to form CME Group. CBOT and three other exchanges (CME, NYMEX, and COMEX) now operate as designated contract markets (DCM) of the CME Group. The concerns of U.S. merchants to ensure that there were buyers and sellers for commodities have resulted in forward contracts to sell and buy commodities. Still, credit risk remained a serious problem. The CBOT took shape to provide a centralized location, where buyers and sellers can meet to negotiate and formalize forward contracts. An early 1848 discussion between Thomas Richmond and W. L. Whiting regarding the propriety of creating a board of trade led to the March 13 meeting merchants and businessmen in favor of establishing it and a resulting resolution for such an establishment and a Constitution. A committee then developed bylaws that were adopted on the first Monday of April by 82 charter members of the Board of Trade. In 1864, the CBOT listed the first ever standardized "exchange traded" forward contracts, which were called futures contracts. In 1919, the Chicago Butter and Egg Board, a spin-off of the CBOT, was reorganized to enable member traders to allow future trading, and its name was changed to Chicago Mercantile Exchange (CME). The Board's restrictions on trading after hours on any prices other than those at the Board's close gave rise to the 1917 case Chicago Board of Trade v. United States, in which the U.S. Supreme Court held that the Sherman Antitrust Act of 1890's language outlawing "every contract ... in restraint of trade" was not to be taken literally, but rather should be interpreted under a "rule of reason." On October 19, 2005, the initial public offering (IPO) of 3,191,489 CBOT shares was priced at 80.50 (USD) on the NYSE. In 2007, the CBOT and the Chicago Mercantile Exchange merged to form the CME Group.