Strategic data sales with partial segment profiling

We analyse the incentives of a data broker to sell consumer-level data that enable personalised pricing to compete with firms when only a fraction of consumers - centred around one firm that we label "central" - are profiled. The central firm can potentially benefit from the data more than the rival ones ("peripheral"). We show that the data broker may decide not to sell the dataset to the central firm and instead trade with its peripheral competitors. In particular, we identify a strategic reaction of competitors that want to prevent that data increase competition.