Are leniency programs too generous?

I present a simple model of collusion in which the competition authority offers leniency rates contingent on the number of firms that report information. The optimal leniency policy involves what I refer to as a single informant rule—that is, leniency should be given only when a single firm reports information. The single informant rule allows to increase expected sanctions compared to the first informant rule, which overall improves cartel deterrence.     

The effect of leniency programs on endogenous collusion

The objective of a leniency program is to reduce sanctions against collusion if a participant voluntarily confesses his behavior or cooperates with the public authority’s investigation. Constructing a model in which the detection probability varies over time, Harrington (2008) pointed out that there are three channels through which the leniency program can affect the collusion amount; furthermore, he presented a sufficient condition under which the maximum leniency is optimal. After extending the model by endogenizing the degree of collusion as well as equilibrium selection in the self-reporting stage, we revealed that the Race to the Courthouse effect disappears and that the maximum reduction is always optimal.     

Collusive behavior under a leniency program

We investigate how a leniency program, which is a policy that gives reduced penalties to colluding firms that cooperate with investigations of the Antitrust Authority, affects firms’ collusive behavior. Using a model of quantity competition, we show that an amnesty to the second or later candidates of a leniency program is of no use if colluding firms can choose the most profitable collusion. Because a leniency program is a general rule that is applied to various markets in a country, our result implies that the design of a leniency program depends on which kinds of market structure are prevalent in the country.     

When imperfect collusion is profitable

This paper studies cartel stability under the assumption that member firms can choose intermediate degrees of collusion as well as the joint-profit-maximizing solution in determining the quota to be produced by each firm. After showing that firms can increase the number of participants by decreasing the degree of collusion, I prove that individual members' profits are maximized when firms choose a (possibly low) degree of collusion such that all firms in the industry want to take part in the cartel. More precisely, if the number of firms in the industry is four or less, then all of them want to take part in the cartel even if the maximum degree of collusion is chosen (i.e., the monopoly output is produced); if the number of firms is greater than four, firms will still create an industry-wide cartel but they will produce a higher quantity than the monopoly output.     

Bidder collusion

We analyze bidder collusion at first-price and second-price auctions. Our focus is on less than all-inclusive cartels and collusive mechanisms that do not rely on auction outcomes. We show that cartels that cannot control the bids of their members can eliminate all ring competition at second-price auctions, but not at first-price auctions. At first-price auctions, when the cartel cannot control members’ bids, cartel behavior involves multiple cartel bids. Cartels that can control bids of their members can suppress all ring competition at both second-price and first-price auctions; however, shill bidding reduces the profitability of collusion at first-price auctions.     

INTERNATIONAL ANTITRUST ENFORCEMENT AND MULTIMARKET CONTACT*

This article analyzes cartel formation and international antitrust enforcement when multinational firms operate in several jurisdictions with local antitrust authorities. We are concerned with how the sustainability of collusion in one local market is affected by the existence of collusion in other markets when they are linked by a negative demand relationship. The interdependence of cartel stability across markets leads to potential externalities in antitrust enforcement across jurisdictions. Local antitrust enforcement equilibrium enforcement may exhibit a nonmonotonicity in the degree of market integration. We compare it with globally optimal antitrust enforcement policy and discuss the role of international antitrust coordination.     

Strictness of leniency programs and asymmetric punishment effect

We analyze the impact of leniency programs on the behavior of firms participating in illegal cartel agreements in a two-stage repeated game model. Our approach takes into account asymmetric punishment effect and allows to discuss the design of leniency programs in the setting with asymmetries. The main contribution of the paper is that we consider heterogeneous firms. This heterogeneity results in additional costs in case of disclosure of the cartel, which are caused by asymmetric punishments. Next, following current antitrust rules, we analyze effects of the strictness of leniency programs, which reflects the likelihood of getting a complete exemption from fine even in case many firms self-report simultaneously. Our main conclusion is that leniency programs work better for small companies, since a lower rate of law enforcement is needed in order to induce self-reporting by smaller firms, while big firms are less likely to start a cartel in the first place given the possibility of self-reporting in future. Finally, we analyze optimal enforcement strategies of the antitrust authority and conclude that the authority with limited resources should implement more generous leniency rules the more cartelized the economy is.     

Leniency policies and illegal transactions

We study the consequences of leniency—reduced legal sanctions for wrongdoers who spontaneously self-report to law enforcers—on sequential, bilateral, illegal transactions, such as corruption, manager–auditor collusion, or drug deals. It is known that leniency helps deterring illegal relationships sustained by repeated interaction. Here we find that—when not properly designed—leniency may simultaneously provide an effective governance mechanism for occasional sequential illegal transactions that would not be feasible in its absence.     

CARTEL STABILITY AND THE CURVATURE OF MARKET DEMAND*

The stability of collusion is analysed for a family of demand functions whose curvature is determined by a parameter varying between zero and infinity. When the number of firms is low, firms may prefer to act as quantity setters in order to increase cartel stability if demand is sufficiently convex. Otherwise, price-setting behaviour enhances their ability to collude. As the number of firms tends to infinity, Cournot behaviour is preferable to Bertrand behaviour in order to stabilize collusion, independently of the characteristics of market demand.     

Technology and Cartel Stability under Vertical Differentiation

The interplay between R&D activity and cartel stability is investigated in a vertical differentiation framework with convex costs. The behaviour of firms' critical discount factors as the curvature of the cost function varies is investigated, considering either price- or quantity-setting behaviour. In order to stabilize collusion, firms are better off playing à la Cournot and supplying the non-cooperative qualities. There emerges a tradeoff between the reduction of the convexity of the cost function and the associated increase in marginal cost. The decision to carry out joint or independent ventures in research is also investigated, showing that such a decision is non-monotone in intertemporal discounting. Policy measures are then briefly discussed.     

A note on cartel stability and endogenous sequencing with tacit collusion

We use the concept of cartel stability defined by d’Aspremont et al. (Can J Econ 16(1):17–25, 1983) to obtain that the sequence of play between the cartel and the fringe affects cartel stability in a quantity-competition setting where firms tacitly collude. We also prove that an endogenous sequence of play between a cartel and a fringe depends on the discount factor. If the discount factor is large enough, the cartel and the fringe simultaneously choose quantities since the stable cartel may contain more firms under simultaneous play than under cartel leadership. This is due to the fact that under simultaneous play cartel firms have incentives to participate in the cartel because otherwise no collusion is possible.      

On prices’ cyclical behaviour in oligopolistic markets

We revisit the discussion about the relationship between price’s cyclical features, implicit collusion and the demand level in an oligopoly supergame where a positive shock may hit demand and disrupt collusion. The novel feature of our model consists in characterising the post-shock noncooperative price and comparing it against the cartel price played in the last period of the collusive path, to single out the conditions for procyclicality to arise both in the short and in the long-run. This poses an issue in terms of an antitrust agency’s ability to draw well defined conclusions on the firms’ behaviour after the occurrence of the shock, with particular reference for the litigation phase after a cartel breakdown.     

Endogenous Cartel Formation

This paper investigates the endogenous formation of cartels in a supergame framework in which cheating on the cartel agreement results in the ejection of only the defector from the cartel while collusion continue s amongst the non-cheating members. A more sophisticated notion of cartel stability than has been analysed hitherto is developed here, and it is shown that cartels are even less stable than they are generally believed to be. When firms produce heterogeneous goods and set prices, cartels comprising a small fraction of the industry's firms are shown to be viable. The emergence of two or more cartels within the same industry is seen not only to be a distinct possibility but also to be quite likely     

Cartel formation and managerial incentives

We study the formation of cartels within two different contexts. First, we consider internal–external stability based models which, due to firms’ free-riding incentives, lead to the inexistence of stable cartels. Second, we introduce the dynamic aspect of coalition formation. That is, when considering a cartel we consider also any cartel that can be reached through a succession of moves. Despite firms’ free-riding incentive, the dynamic process predicts that the collusion of the whole industry can occur with some regularity. We show that free-riding incentives decrease and incentives to merge increase when firms’ owner delegate production decisions to managers.      

ON THE SUSTAINABILITY OF COLLUSION IN A DIFFERENTIATED OLIGOPOLY WITH A CARTEL AND A FRINGE

We discuss the effects of the existence of non‐colluding (fringe) firms on cartel sustainability. We obtain, using trigger strategies, that with product differentiation collusion is always more easily sustained when firms compete in prices than when firms compete in quantities. This is true basically because (i) price competition is more intense than quantity competition, and (ii) fringe firms exacerbate the fact that cartel firms have more incentives to deviate from the agreement under quantity competition. This result reverses previous findings where, in the absence of fringe firms, product differentiation plays a crucial role in determining the effectiveness of price or quantity competition in sustaining collusion.     

Vox Populi,Vox Dei? Tacit collusion in politics

We study competition between political parties in repeated elections with probabilistic voting. This model entails multiple equilibria, and we focus on cases where political collusion occurs. When parties hold different opinions on some policy, they may take different policy positions that do not coincide with the median voter's preferred policy platform. In contrast, when parties have a mutual understanding on a particular policy, their policy positions may converge (on some dimension) but not to the median voter's preferred policy. That is to say, parties can tacitly collude with one another, despite political competition. Collusion may collapse, for instance, after the entry of a new political party. This model rationalizes patterns in survey data from Sweden, where politicians on different sides of the political spectrum take different positions on economic policy but similar positions on refugee intake—diverging from the average voter's position, but only until the entry of a populist party.     

Price vs quantity in a duopoly supergame with Nash punishments

We examine the endogenous choice between price and quantity behaviour in a duopoly supergame with product differentiation. We find that (i) if cartel profits are evenly split between firms, then only symmetric equilibria s obtained; (i) if instead the additional profits available through collusion are split according to the Nash bargaining solution, there are parameter regions where all subgame perfect equilibria are asymmetric, with firms colluding in price–quantity supergames.     

Collusive behaviour under cost asymmetries when firms compete in supply functions

This paper investigates the effect of cost heterogeneity in cartel formation and its sustainability over time when firms compete in supply functions under uncertainty. We find that cartel formation and collusion sustainability are hindered as cost differences increase. Efficiency losses caused by collusive behaviour are shown to decrease as asymmetry increases and, therefore, welfare losses also decrease. We compare our results with those obtained under Cournot and Bertrand competition.     

Cartel sustainability with vertical product differentiation: Price versus quantity competition

In the context of a vertically differentiated duopoly, we analyse the influence of the degree of differentiation on cartel sustainability, under both price and quantity competition. We find that, under both Bertrand and Cournot competition, the effect of vertical product differentiation on sustainability of the collusive equilibrium is unclear. It is shown that, given a degree of differentiation, price collusion is more sustainable than quantity collusion.     

Legal Principles in Antitrust Enforcement

We study antitrust enforcement that aims to channel price‐fixing incentives of cartels through setting fine schedules and detection levels. Fines obey legal principles, such as the punishment should fit the crime, proportionality, bankruptcy considerations, and minimum fines. Bankruptcy considerations limit maximum fines, ensure abnormal cartel profits, and impose a challenge for optimal antitrust enforcement. We derive the fine schedule and detection level that are constrained‐optimal under legal principles and sustainability of cartel prices. This fine schedule lies below the maximum fine, makes collusion on lower prices more attractive than on higher prices, and, hence, relates to the body of literature on marginal deterrence.