Mt. Gox
Launch
2010
Death / Exploit
February 2014
Total Loss
$450 Million
At one time, Mt. Gox alone handled 70% of the world's Bitcoin trade. However, due to internal mismanagement and a hack that went undetected for years, its security continued to drain. In 2014, it was discovered that 850,000 BTC had been stolen. The exchange stopped withdrawals overnight and filed for bankruptcy.