The paper discusses the respective roles of competition policy and sector-specific regulation for industries such as telecommunications, electricity, and gas, in which network infrastructures that are natural monopolies serve as essential facilities for anybody who wants to provide services in...

By using general information structures and precision criteria based on the dispersion of conditional expectations, we study how oligopolists’ information acquisition decisions may change the effects of information sharing on the consumer surplus. Sharing information about individual cost...

Anti-trust cases more often than not hinge upon market definition. The anti-trust authorities use standardised tests for the purpose, like the "small but significant and nontransitory increase in price" test prevalent in US law. These tests are often read as neoclassical economics, watered down...

This paper analyzes the impact vertical integration has on upstream collusion when the price of the input is linear. As a first step, the paper derives the collusive equilibrium that requires the lowest discount factor in the infinitely repeated game when one firm is vertically integrated. It...

Antitrust authorities all over the world are concerned if a particularly aggressive competitor, a "maverick", is bought out of the market. Yet there is a lack of theoretical justification. One plausible determinant of acting as a maverick is behavioral: the maverick derives utility from acting...

Cartels are inherently instable. Each cartelist is best off if it breaks the cartel, while the remain-ing firms remain loyal. If firms interact only once, if products are homogenous, if firms compete in price, and if marginal cost is constant, theory even predicts that strategic interaction...

This paper analyzes the role of the reference period in assessing switching costs in retroactive rebates. A retroactive rebate allows a firm to use the inelastic portion of demand as leverage to decrease price in the elastic portion of demand, thereby artificially increasing switching costs of...

Two suppliers of a homogenous good know that, in the second period, they will be able to collude. Gains from collusion are split according to the Nash bargaining solution. In the first period, either of them is able to invest into process innovation. Innovation changes the status quo pay-off,...

Both in the US and in Europe, antitrust authorities prohibit merger not only if the merged entity, in and of itself, is no longer sufficiently controlled by competition. The authorities also intervene if, post merger, the market structure has changed such that "tacit collusion" becomes...

Triggered by the concentration process in the electricity and gas markets, the land of Hesse proposes to give the German cartel office power to divest dominant firms or oligopolies if this is necessary to restore competition. The paper shows that the reform would be in line with constitutional...