When hackers penetrated a secure authentication system at a bitcoin exchange called Bitfinex earlier this month, they stole about $70 million worth of the virtual currency.
The cybertheft — the second largest by an exchange since hackers took roughly $350 million in bitcoins at Tokyo's Mt. Gox exchange in early 2014 — is hardly a rare occurrence in the emerging world of cryptocurrencies.
Data seen by Reuters shows a third of bitcoin trading platforms have been hacked, and nearly half have closed in the half dozen years since they burst on the scene.