We characterize optimal selling protocols/equilibria of a game in which an Agent ﬁrst puts hidden eﬀort to acquire information and then transacts with a Firm that uses this information to take a decision. We determine the equilibrium payoﬀs that maximize incentives to acquire information. Our analysis is similar to ﬁnding ex ante optimal self-enforcing contracts since information sharing, outcomes and transfers cannot be contracted upon. We show when and how selling and transmitting information gradually helps. We also show how mixing/side bets increases the Agent’s incentives.