Mergers - the CMA’s jurisdiction and procedure: CMA2

Guidance for businesses and their advisers on CMA's procedures for operating the merger control regime under the Enterprise Act 2002.


Mergers: Guidance on the CMA’s jurisdiction and procedure

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This guidance provides advice and general information to companies and their advisers on the procedures used by the Competition and Markets Authority (CMA) in operating the merger control regime set out in the Enterprise Act 2002, as amended. It also includes guidance on when the CMA will have jurisdiction to review mergers under the Act.

This guidance focuses on mergers involving UK companies, but briefly addresses mergers that fall to the European Commission under the European Union Merger Regulation.

The following forms and templates are also available:

Please note that Water and sewerage mergers: Guidance on the CMA’s procedure and assessment (CMA49) has now replaced paragraphs 17.1 to 17.6 of this guidance.

Any merger that qualifies for reference for a phase 2 investigation is subject to a fee. This is irrespective of whether a reference is made. Further information on the fees and how to pay them are in the merger fees information document. The merger fees document includes changes to the criteria for small and medium-sized enterprises set out in paragraph 20.6 of this guidance.

The fines that could be imposed on summary conviction for certain criminal offences referred to in this document were, at that time, subject to specific caps of £5,000 or above. With effect from 12 March 2015, these caps have been removed and those specific offences are now punishable by a fine of any amount. For more information see the Ministry of Justice news story.

Published 10 January 2014
Last updated 11 April 2014 + show all updates
  1. Added Water mergers explanatory note
  2. First published.