Summary

On November 19, 2021, Coinbase learned that it had erroneously credited some customers transacting in GYEN and POWR either 100x or 1/100th the amount they purchased. Coinbase promptly disabled trading in POWR and GYEN, worked around the clock to resolve the underlying technical issue, and then made adjustments in customer accounts to reflect the amount of GYEN and POWR that customers actually purchased. This incident affected approximately 0.0072% of Coinbase’s total verified users.

What happened?

On November 19 at approximately 4:00 p.m. EST, Coinbase updated an internal data source related to POWR and GYEN precision. The update was tested through our standard automated testing and deployment monitoring procedures. However, the testing didn’t detect that the update would propagate at various speeds through a number of internal systems and would result in customers being credited either 100x or 1/100th the amount of GYEN or POWR they purchased.

The data rollout error was identified through our position risk monitoring systems shortly after the November 19 4:00 p.m. EST update. At 5:35 p.m. EST, we disabled transacting in GYEN and POWR pending resolution of the underlying issue. At 7:26 p.m. EST, we identified accounts that transacted in GYEN or POWR during the data rollout, and temporarily restricted these accounts pending further investigation. By November 21, restrictions were removed for 98.8% of these accounts and, by December 13, Coinbase restored full trading for GYEN and POWR.

What did Coinbase do to correct the problem?

Coinbase immediately devoted…