Bitcoin Falls on $31 Million Hack of Cryptocurrency Peer Tether

Bitcoin slipped from a record after the $31 million theft of a cryptocurrency peer renewed concern about the security of digital coins.

The company behind tether, a cryptocurrency used by bitcoin exchanges to facilitate trades with fiat currencies, announced the theft on Tuesday. It said in a statement that a “malicious” attacker removed tokens from the Tether Treasury wallet on Nov. 19 and sent them to an unauthorized bitcoin address. The company said it’s trying to prevent the stolen coins from being used.

Bitcoin dropped as much as 5.4 percent to $7,798.72, before paring declines to 0.7 percent at 9:20 a.m.

The incident is the latest in a long list of hacks that have dented confidence in the safety of cryptocurrencies. It’s likely to fuel the debate on Wall Street over whether digital coins are secure enough to enter the mainstream of finance.

Tether, with a market capitalization of $676 million, is the world’s 19th most-valuable virtual currency, according to data on Coinmarketcap.com. The tokens are pegged to fiat currencies, allowing users to store and transfer globally and instantly, according to the website. The company behind tether has said that the tokens are 100 percent backed by fiat currencies.

Tether has become part of the bitcoin ecosystem because it helps exchanges facilitate trades against currencies like the dollar, euro and yen, according to Arthur Hayes, chief executive officer of BitMEX, a cryptocurrency derivatives venue in Hong Kong. Anti-money laundering and know-your-customer rules have prevented many bitcoin exchanges from opening bank accounts needed to hold fiat currencies.

The theft has renewed concerns over tether’s viability. Skepticism had already been building after the company behind the tokens said in April that all international wires had been blocked by its Taiwanese banks. That fueled speculation about whether the tokens were fully backed back fiat currencies.

“If tether is actually fundamentally compromised, that will be a very big issue for many exchanges,” Hayes said. “The knee-jerk reaction was that fear.”