This document describes three types of copyright protection technologies in use in the publishing industry: —     digital rights management (DRM) free protection, i.e. technologies which do not rely on content encryption but rather use content fingerprinting or watermarking, adequate for use cases where user convenience is the top priority; —     user key-based DRM protection, adequate where user constraints are limited; —     device key-based DRM protection, adequate where the transfer of publications from one device to another is severely constrained.