We consider a private-value auction with one-sided incomplete information in which two objects are sold in a sequence of two second-price auctions. The buyers have multiunit demand and are asymmetrically informed at the ex ante stage of the game. One buyer perfectly knows his type, and the other...

We study the implications of delegating bids to a bidding agency for the revenues and efficiency of the Generalized Second-Price auction, the standard sales mechanism for allocating online ad space. The agency maximizes both its own profits and the advertisers' surplus and implements collusive...