We analyze a setting common in privatizations, public tenders, and takeovers in which the ex post efficient allocation, i.e., the first best, is not implementable. Our first main result is that the open ascending auction is not second best because it is prone to rushes, i.e., all active bidders...

Reserve prices are used by sellers to modify the allocation induced by standard auctions. The existing literature has shown that, if the number of bidders is fixed, a reserve price can be used to increase expected revenues. This comes at the expense of efficiency when the auctioned good goes...

We analyze the rationale for hiding information in open auction formats. In particular, we focus on the incentives for a bidder to call a price higher than the highest standing one in order to prevent the remaining active bidders from aggregating more accurate information that could be gathered...