Information revelation in auctions with common and private values

We explore the incentives to reveal verifiable private information when there are both common and private components to agents' valuations and when private information is held in both dimensions. When agents observe only one signal, they have no incentive to reveal the signal because such a revelation would negate their information advantage. However, when agents observe multiple signals, they may be incentivized to reveal certain signals that could lower their opponents' bids and thereby result in a higher profit from other signals. This paper shows that there exists an equilibrium with revelation of common-value signals in standard auctions, which is an efficient equilibrium that maximizes the social welfare and could provide the seller with a higher profit than a situation with no information revelation.