The competitive allocation process is informationally efficient uniquely
Abstract This paper establishes that the competitive allocation process is the only informationally decentralized mechanism for exchange environments which (i) achieves Pareto optimal allocations; (ii) gives each consumer an allocation which is, according to his preferences, at least as good as his endowment; (iii) satisfies certain regularity conditions; and (iv) has a message space of the smallest dimension necessary to satisfy (i–iii).