Encyclopedia of Law and Economics

2019 Edition
| Editors: Alain Marciano, Giovanni Battista Ramello

Merger Control

  • Tim ReuterEmail author
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-7753-2_320


Merger control is at the heart of competition law institutions throughout the world. Firms, before they complete a merger or an acquisition, are required to get the transaction approved by competition authorities. The objectives of merger control, limiting the accrual of market power and protecting the welfare-generating competition forces of the market, are well in line with economic theory. Economic theory has identified several types of effects that can arise from a merger, in particular unilateral and coordinated horizontal effects that result from an elimination of competition between firms supplying substitutable goods, and non-horizontal and conglomerate effects that result if firms are active on vertically or otherwise linked markets. We discuss the reasoning behind these effects and how they are assessed by competition authorities. We also discuss market definition as a first step in the assessment of mergers and the legal framework under which mergers are controlled.

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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.RBB EconomicsBrusselsBelgium