This essay critically analyzes Luciano Floridi’s ontological theory of informational privacy. Organized into two main parts, Part I examines some key foundational components of Floridi’s privacy theory and it considers some of the ways in which his framework purports to be superior to alternative theories of informational privacy. Part II poses two specific challenges for Floridi’s theory of informational privacy, arguing that an adequate privacy theory should be able to: (i) differentiate informational privacy from other kinds of privacy, including psychological (...) privacy; and (ii) distinguish between descriptive and normative aspects of informational privacy in a way that differentiates a (mere) loss of privacy from a violation of privacy. I argue that Floridi’s privacy theory, in its present form, does not explicitly address either challenge. However, I also argue that his ontological theory provides us with a novel way of analyzing the impact that digital technologies have had for informational privacy. I conclude by suggesting that Floridi’s privacy framework can be interpreted as containing the elements of a “personality theory of privacy,” which would be useful to examine in a separate study. (shrink)