  This paper argues that data of strategic individuals with heterogeneous
privacy valuations in a distributed online social network (e.g., Facebook) will
be under-priced, if traded in a monopoly buyer setting, and will lead to
diminishing utilitarian welfare. This result, for a certain family of online
community data trading problems, is in stark contrast to a popular information
economics intuition that increased amounts of end-user data signals in a data
market improves its efficiency. Our proposed theory paves the way for a future
(counter-intuitive) analysis of data trading oligopoly markets for online
social networks (OSNs).
