At Coinbase we go to great lengths to keep all of your sensitive information safe.
Account numbers and routing numbers are stored using bank level AES-256 encryption on our servers. In addition, all traffic goes over SSL to prevent third parties from eavesdropping on your connection. Employee access is heavily restricted and we require background checks on all employees.
If you choose "Instant Account Verification" you can verify your account in just a few minutes by entering your bank credentials. You may be familiar with this process if you've ever verified a bank account on Paypal. These banking usernames and passwords are never stored in our database, and are discarded after the one-time verification step. They are used once and immediately removed from our system. We also take great care to ensure they are filtered from any log files on our servers.
You can read more on our Security Page.
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