Influencer marketing is a large and growing but mostly unregulated industry. We document the existence and study cartels of influencers. Using a novel dataset of Instagram influencer cartels, we confirm that the cartels increase engagement as intended. But we also show that engagement from...

We study optimal cartel prices in a two-sided market. We present a simple model showing that prices above the two-sided monopoly price may prevail on one side of a two-sided market as a means to enhance the sustainability of the cartel. We prove that in such a case a higher benefit from the...

Leniency programs as a tool for cartel detection and cartel destabilization, have been implemented since the early nineties. Theoretical work has shown that leniency programs can be effective in enhancing cartel detection and deterrence, but these effects are not straight-forward. It is even...

For a general class of oligopoly models with price competition, we analyze the impact of ex-ante leniency programs in antitrust regulation on the endogenous maximal-sustainable cartel price. This impact depends upon industry characteristics including its cartel culture. Our analysis disentangles...

We analyze maximal cartel prices in infinitely-repeated oligopoly models under leniency where fines are linked to illegal gains, as often outlined in existing antitrust regulation, and detection probabilities depend on the degree of collusion. We introduce cartel culture that describes how...

We analyze how leniency affects cartel pricing in an infinitely-repeated oligopoly model where the fine rates are linked to illegal gains and detection probabilities depend on the degree of collusion. A novel aspect of this study is that we focus on the worst possible outcome. We investigate the...

The paper assesses the impact of the detection of a hard-core cartel in the Swiss market for road surfacing on post-cartel competition. In addition to an investigation of supply-side factors, demand-side factors, and market prices, the paper also derives estimates of the economic effects of the...

From the perspective of competitors, competition may be modeled as a prisoner's dilemma. Setting the monopoly price is cooperation, undercutting is defection. Jointly, competitors are better off if both are faithful to a cartel. Individually, profit is highest if only the competitor(s) is (are)...

Leniency policies and rewards for whistleblowers are being introduced in ever more fields of law enforcement, though their deterrence effects are often hard to observe, and the likely effect of changes in the specific features of these schemes can only be observed experimentally. This paper...

Although the pricing dynamics of hardcore cartels have been studied intensively from a theoretical perspective, empirical evidence is still rare. We combine publicly available data with a unique private data set of about 340,000 market transactions from 36 smaller and larger customers of German...