We study a first-price auction preceded by a negotiation stage with complete information, during which bidders may form a bidding ring. We prove that in the absence of externalities, the grand cartel forms in equilibrium, allowing ring members to gain the auctioned object for a minimal price....

A mistake in “Five legitimate definitions of correlated equilibrium (CE) in games with incomplete informationâ€\x9D motivates a re-examination of some extensions of the solution concept that Aumann introduced. Copyright Springer 2006