Coinbase Stock Slips as Crypto Exchange Informs SEC of Customer Data Breach

Coinbase Global (COIN) stock moved lower in premarket trading Thursday after the company said in a regulatory filing that it had been the victim of a cyberattack.

The online cryptocurrency exchange said that it received “an email communication from an unknown threat actor claiming to have obtained information about certain Coinbase customer accounts, as well as internal Coinbase documentation” on May 11. The company added that “the threat actor appears to have obtained this information by paying multiple contractors or employees working in support roles outside the United States to collect information from internal Coinbase systems to which they had access.”

Coinbase Estimates Costs at $180M to $400M

“The communication demanded money in exchange for not publicly disclosing the information,” the filing said. Coinbase said it has not paid the demand and is working with law enforcement. Its investigation is still ongoing, but Coinbase said it expects the incident to cost between roughly $180 million and $400 million “relating to remediation costs and voluntary customer reimbursements.”

Coinbase said no passwords or customer funds were ever accessed. However, it said names, addresses, phone numbers, email addresses, last four digits of Social Security numbers, masked bank account numbers, and Coinbase account data like “balance snapshots and transaction history” may have been compromised.

Shares were down more than 2% an hour before the opening bell Thursday. They had surged earlier this week on news that Coinbase will join the S&P 500 next Monday.