One of the big challenges of scaling a backup service is maximizing the upload rate from customers, so there's a strong incentive to do the de-duplication befor

One of the big challenges of scaling a backup service is maximizing the upload rate from customers, so there's a strong incentive to do the de-duplication before the upload when possible. I don't wish to call anyone out specifically, but several storage services operate exactly in this way. I disagree that requiring end-users to effectively operate their own encryption software is a robust path to privacy.