Substantial Lessening of Competition
The statutory test the Competition and Markets Authority applies in UK merger control: whether a merger has resulted, or may be expected to result, in a substantial lessening of competition (SLC) in a UK market.
Independent editorial summary — not the official statute text. Read the official version on legislation.gov.uk.
Section 22 of the Enterprise Act 2002 requires the Competition and Markets Authority to refer a completed merger for an in-depth investigation if it believes that a relevant merger situation has been created and that the creation of that situation has resulted, or may be expected to result, in a substantial lessening of competition within any market or markets in the United Kingdom for goods or services. An equivalent duty applies to anticipated mergers under section 33.
The CMA can decide not to make a reference where the market concerned is not of sufficient importance to justify one, or where it believes any relevant customer benefits in relation to the creation of the relevant merger situation concerned outweigh the substantial lessening of competition. Where the CMA does find a substantial lessening of competition, it can require remedies such as divestment or behavioural undertakings, or, in the most serious cases, block the merger.
Related terms
Official sources
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