Bitcoin promoter Charlie Shrem walks out of federal court in Lower Manhattan, New York September 4, 2014. Shrem pleaded guilty on Thursday to operating an unlicensed money transmitting business, resolving U.S. charges that he helped to sell more than $1 million of the digital currency to users of the illicit online drug marketplace Silk Road. Shrem and his accused co-conspirator, Robert Faiella, pleaded guilty at a hearing in New York federal court as part of a deal struck with prosecutors from the office of Manhattan U.S. Attorney Preet Bharara. REUTERS/Adrees Latif (UNITED STATES - Tags: BUSINESS CRIME LAW)