Thieves stole at least $533 million in an attack against Coincheck, Japan’s largest cryptocurrency exchange, the company’s president and chief operating officer said at a press conference at the Tokyo Stock Exchange on Friday.
This is the largest cryptocurrency theft of all time, eclipsing the historic 2014 heist against Mt. Gox in which the coins were valued at $450 million USD. The coins were sent “illicitly” outside Coincheck.
The company plans to repay around $425 million to users, they said on Monday, but offered no specifics on how and when the repayment would materialize.
Neither the method of attack nor the full amount lost are known publicly at this point. The amount lost was originally thought to be around $400 million USD and now further investigation is required to see if even more than $533 million USD has been stolen.
Thieves stole the full value in NEM tokens, a Japanese-based coin that has one of the highest total market values among cryptocurrencies. The price of NEM has fallen by about 11 percent since Coincheck’s troubles began.
Launched in 2012, Coincheck is headquartered in Tokyo and boasts over $40 billion in bitcoin transaction volume every month. The company says it has a 99 percent market share in Japan for bitcoin payment processing.
Rumors of the theft began circulating when Coincheck froze services early on Friday morning.
Currently, credit card, Pay Easy, and convenience store payments are suspended. We sincerely apologize for these inconveniences and will continue to do our best to be back to normal operations as soon as possible.
— Coincheck (@coincheck_en) January 26, 2018
Japanese police and the country’s Financial Services Agency is currently investigating Coincheck which, it was revealed today, had not previously registered with the agency.
This is a developing story and will be updated as information becomes available.
Update: A previous version of this article referred to ‘hackers’ stealing the cryptocurrency. The language has been updated to ‘thieves’ because, as previously explained, it is not clear at all how the cryptocurrency was taken except that it was done-so “illicitly” according to Coincheck.
Update 2: Coincheck plans to repay at least some of the lost money to users.