Coinbase stores one private key that we can access, and one private key that is encrypted with the user's vault password on the front-end and sent to us encrypted for storage. The third key is the user's and we never see that.
We have no ability to access multisig vault funds without the user passphrase, which never touches our server.
We have no ability to access multisig vault funds without the user passphrase, which never touches our server.