The closest thing to private data we store is the user's email, which is needed as a basic identifier so we can provide our service. For premium (paid) users only, a minimal amount of private data is stored with our payment processor, Stripe. The data that is stored is that which was provided by the user at checkout/sign-up. This typically includes email, name, billing address and credit card. We typically also append the IP address that a user signed up from (for possible future fraud prevention or mitigation purposes) to the Stripe data. Active users generally cannot have this data deleted since it is needed to maintain a subscription.