CMS E-Guide to Mer­ger Con­trol


Merger transactions, including many joint ventures, which affect European markets can face merger control either at European Union (EU) level by the European Commission, or at national level by the relevant national competition authorities of EU Member States. They may also be reviewed by other European and other national merger control authorities outside the EU. This guide gives an overview of the main merger control rules at EU level and in all European countries. This guide includes 45 jurisdictions and 43 countries.

Whichever rules apply, it is important for the parties to ensure that any compulsory pre-merger notification is made and any standstill periods are respected. Even where pre-merger notifications are not compulsory, parties should take account of the risk of proceeding to implement the transaction without (voluntary) prior notification and approval, insofar as the relevant national authorities could order a divestment or other separation of assets or entities following a subsequent investigation and opposition to the transaction.

The treatment of mergers and concentrations does vary as between EU rules and the national rules of the various different EU and other European countries. This manual summarizes the key features of each regime using a consistent, thematic approach. The guide is intended to facilitate a rapid overview of the relevant rules at EU level and in each of the countries of Europe. The rules are explained in each case by reference to the following questions:

  • Which authority is to be notified and what is the source for merger control regulations?
  • Is a notification mandatory or voluntary?
  • When do you need to notify?
  • What are the thresholds?
  • Who is obliged to notify?
  • What are the consequences of:
    • failure to notify,
    • implementing the transaction despite an obligation to suspend until clearance; and
    • implementing the transaction despite a prohibition decision?
  • What are the stages of merger control?
  • Are foreign-to-foreign mergers caught?
  • How are JVs treated?

The CMS E-Guide to Merger Control is available at:


Harald Kahlenberg
Dr. Harald Kahlenberg