UK market investigations

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In the UK, the Competition and Markets Authority (CMA) has the power to investigate markets to review how competition is working (or not) in a UK market or broader sector—even where there is no evidence of an infringement of UK competition law. In other words, these market reviews are not normally used by the CMA to deal with allegations that a company has breached competition law (though they may lead to possible breaches being uncovered) but rather to look at broader structural concerns.

This sub-topic contains detail on the processes for market studies and market investigations carried out by the CMA (and sectoral regulators).

Background and legal basis

The UK's market investigation powers originally formed part of monopoly reference provisions of the Fair Trading Act 1973. These powers were retained even after the introduction of the Competition Act 1998 on the grounds that they permitted market-wide investigations by the then Competition Commission. However, these powers were ultimately subsumed within the Enterprise Act 2002 with Section 131(1) (as amended by the Enterprise and Regulatory Reform Act 2013) providing the CMA the power (based on a discretion

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Latest Competition News

No right to full compensation following divestment order under the National Security and Investment Act (R (on the application of L1T FM Holdings Ltd and Letterone Core Investments Sàrl) v Chancellor of the Duchy of Lancaster in the Cabinet Office)

Banking and Finance analysis: This news analysis looks at the decision in L1T FM Holdings Ltd, in which the Court of Appeal agreed with the High Court that the Article 1 of Protocol 1 of the ECHR did not require full compensation to be made following a forced sale under the National Security and Investment Act 2021.

EU Competition law—daily round-up (12/12/2025)

A round-up of EU competition law developments, including (amongst other things) the latest State aid developments.

Competition weekly highlights—11 December 2025

This week's edition of Competition weekly highlights includes, from a UK perspective: (1) the CMA's decision that Vandemoortele/Délifrance merger meets the test for reference to phase 2, (2) the CMA's decision to launch a strategic review of legacy merger remedies, (3) a Court of Appeal's judgment upholding the dismissal of LetterOne's compensation claim following a NSI Act 2021 divestment order, (4) a High Court judgment dismissing Brazilian orange growers' cartel damages claims as time-barred under Brazilian law, and (5) publication by the CMA Microeconomics Unit of a report on technology, productivity and competition. This week's highlights also include, from an EU perspective: (1) a General Court judgment reducing Intel's ‘naked restrictions’ fine but rejecting annulment, (2) a General Court judgment dismissing an action against the Commission's rejection of a complaint in the Fire Protection Bogies case, (3) the Commission's decision to launch an investigation into Meta's restrictions on AI providers' access to WhatsApp, (4) the Commission's decision to launch an investigation into Google's use of publisher and YouTube content for AI training, (5) the Commission's decision to unconditionally clear Mars/Kellanova after phase II, (6) the Commission's decision to refer TIL/Hutchison Ports/TERCAT to phase II, (7) Meta's commitment to give EU users choice on personalised ads under DMA, and (8) a General Court judgment dismissing an action against the Commission's decision to approve restructuring aid of €2.55bn granted to Portugal to TAP.

UK Competition law—daily round-up (11/12/2025)

A round-up of UK competition law developments, including the latest UK merger control developments.

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