Compromised user accoutns: 190k
Assets stolen: 450M USD
Mt. Gox, the most popular Bitcoin exchange in 2013, declared it had lost all the assets of the customers.
“Mt. Gox was a bitcoin exchange based in Tokyo, Japan. It was launched in July 2010, and by 2013 was handling 70% of all bitcoin transactions. In February 2014, the Mt. Gox company suspended trading, closed its website and exchange service, and filed for a form of bankruptcy protection from creditors called minji saisei, or civil rehabilitation, to allow courts to seek a buyer. In April 2014, the company began liquidation proceedings. It announced that around 850,000 bitcoins belonging to customers and the company were missing and likely stolen, an amount valued at more than $450 million at the time. Although 200,000 bitcoins have since been “found”, the reason(s) for the disappearance—theft, fraud, mismanagement, or a combination of these—are unclear as of March 2014.” (Wikipedia)
Th ex-employees claimed that the owner of Mt. Gox, Mark Karpeles, was embezzling customer funds. It is also suspected Mt.Gox had lost customer Bitcoins and funds during the years and was running on fractional reserver for long time.
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