This paper studies the optimal auction for a seller who is bound to sell a single item to one of two potential buyers organized in a "well-coordinated" cartel. After discussing the way the cartel reacts to any auction mechanism, we show that if the seller has no way to deter collusion, he can...

This paper studies the optimal auction for a seller who is bound to sell a single item to one of two potential buyers organized in a ”well-coordinated” cartel. After discussing the way the cartel reacts to any auction mechanism, we show that if the seller has no way to deter collusion, he...

I consider optimal auctions for a seller who is bound to sell a single item to one of two potential buyers, organized in a `well-coordinated' cartel. I show that, even though the seller cannot deter collusion, he can optimally accommodate it by employing a simple mechanism which imposes an...