I consider a seller selling a good to bidders with two-dimensional private information: their valuation for a good and their characteristic. While valuations are non-verifiable, characteristics are partially verifiable and convey information about the distribution of a bidder’s valuation. I...

Neeman (2004) and Heifetz and Neeman (2006) have shown that, in auctions with incomplete information about payoffs, full surplus extraction is only possible if agents’ beliefs about other agents are fully informative about their own payoff parameters. They argue that the set of...