The ex ante incentive compatible core of an exchange economy with private information is the (standard) core of a … incentive compatible core can be empty, even if utility functions are quasi-linear. If, in addition to quasi-linearity, further … assumptions are made (like independent private values), the non-emptiness of the core follows nevertheless from d'Aspremont and …

incentive compatibility constraints : the associated ex ante core is generically nonempty. However, we exhibit a well …–behaved exchange economy in which this core is empty, even if goods are allocated through random mechanisms. …