When you use VeryPDF DRM Protector to sell protected PDF eBooks, you can create an authorized user for each customer. For example, if you want each customer to read an eBook on a maximum of 2 devices, you can set
How to Build an Automatic eBook Delivery System with PDF Device Limits
Selling PDF eBooks is easy. The difficult part starts after a customer pays. You need to deliver the correct PDF, send the customer a private reading link, stop customers from sharing that link, and control how many devices can open