Dec 12 (Reuters) - INTL FCStone Inc INTL.O :
* INTL FCSTONE INC. AGREES TO ACQUIRE GMP'S US-BASED FIXED INCOME TRADING BUSINESS, FORMERLY KNOWN AS MILLER TABAK ROBERTS SECURITIES, LLC
* INTL FCSTONE INC - TRANSACTION WILL ALSO INVOLVE PURCHASE OF GMP SECURITIES LLC'S U.S.-BASED PARENT