Before revision:  We prove both the existence of a D1 equilibrium and the uniqueness of the equilibrium interim payoff vector for the seller. The uniqueness result holds even if the refinement concept is weakened to the intuitive criterionunder certain regularity conditions. The refined equilibriumpayoff vectors for both players are characterized by the seller's best incentive-feasible allocation among those that are ex post incentive compatible and individually rational for the buyer. The allocation takes a simple format of (almost-)fixed prices if the virtual surplus is strictly increasing in the buyer's type. We show that the privacy of the seller's information causes undersupply of the good and reduces both players' interim payoffs .
After revision:  We refine equilibria by the intuitive criterion. To eliminate each unintuitive equilibrium, we design an indirect mechanism that elicits both parties' common knowledge of the buyer's off-path belief after the mechanism itself is offered. The mechanism uses the elicited belief to decide what allocation is fully implemented. We characterize both parties' interim payoff vectors in intuitive equilibria. The result implies the uniqueness of the seller's information causes undersupply of the good and reduces both players' interim payoffs .