Robustness of the coordinating role of a redundant security

The coordinating role of a redundant security is its role in markets with transaction costs to coordinate different consumers’ security demands so as to clear all security markets and, simultaneously, attain a given commodity allocation. The purpose of this paper is to prove that, under some conditions, the coordinating role of a redundant security is a robust property with respect to perturbations in utility functions, initial endowments, and transaction costs.