An antitrust authority deters collusion using fines and a leniency program. Unlike in most of the earlier literature, our firms have imperfect cumulative evidence of the collusion. That is, cartel conviction is not automatic if one firm reports: reporting makes conviction only more likely, the...

Two firms produce a product with a horizontal and a vertical characteristic. We call the vertical characteristic quality. The difference in the quality levels determines how the firms share the market. Firms know the quality levels, consumers do not. Under non-comparative advertising a firm may...