Mark Karpeles, chief executive officer of Tibanne Co., poses for a photograph with a bitcoin in the office operating the Mt.Gox K.K. bitcoin exchange in Tokyo, Japan, on Thursday, April 25, 2013. Bitcoin digital currency, which carries the unofficial ticker symbol of BTC, was unveiled in 2009 by an unidentified programmer, or group of programmers, under the name of Satoshi Nakamoto. Supply is capped at 21 million Bitcoins and managed by a software algorithm embedded into the digital currency?s design, rather than a monetary authority such as a central bank. Photographer: Tomohiro Ohsumi/Bloomberg via Getty Images