Seller Beware: Supply and Demand Reduction and Price Manipulation in Multiple‐Unit Uniform Price Auctions

We experimentally compare under‐revelation of supply and demand across alternative variations of ascending and descending two‐sided price clock auctions. We find that buyers reduce demand more when the price is ascending but sellers’ behavior is consistent across clock directions. As a result, the clock price rule has empirical effects on efficiency even though it is theoretically neutral.