We analyze the sequential exchange problem in which traders have incomplete information on earlier contracts. We show that under sequential exchange, it is in general not possible to simultaneously implement two key features of markets specialization between asset ownership and control, andimpersonal trade. In particular, we show that in contrast with the conventional wisdom in economics, strong property rights enforceable against subsequent buyers may be detrimental to impersonal trade. Finally, we provide conditions under which a mechanism that overcomes the tradeoff betweenspecialization and impersonal trade exists, and we characterize such mechanism. Our results provide an efficiency rationale for how property rights are enforced in business, company and real estate transactions, and for the ubiquitousness of formalization institutions that the literature has narrowlyseen as entry barriers.