Through a market study or a market investigation the CMA can examine how a whole market works, not just the conduct of a single firm, and impose remedies where competition is not working well. The powers are in Part 4 of the Enterprise Act 2002, strengthened by the Digital Markets, Competition and Consumers Act 2024. For a business in a market under scrutiny, the CMA can impose binding orders that change how it operates, and a business that engages early has more scope to shape them. A business responding to a study or investigation, and a business affected by its outcome, both need to know what the CMA can require and what it will accept.

The regulatory framework

The CMA proceeds in two stages. A market study is its initial examination, carried out on a twelve-month statutory timetable running from the market study notice published under section 130A, with the market study report due within twelve months of that notice under section 131B(4), and can end in no action, undertakings, or a reference to a fuller inquiry. A market investigation is that fuller inquiry, conducted by an independent CMA group over eighteen months, extendable once by up to six months. To make a reference the CMA needs only reasonable grounds for suspecting that features of a market harm competition (section 131); the group makes the full adverse effect on competition finding at the end of the investigation (section 134).

The concept of a “feature of a market” is broad. It covers the structure of the market, the conduct of suppliers or acquirers, and the conduct of customers, and it does not require any intention to harm competition. The CMA can therefore act in digital and platform markets, where the concern is often structural, such as network effects or customer inertia, rather than a specific act of misconduct. Under the DMCC Act 2024, from 1 January 2025 the CMA can make targeted references confined to particular features (section 133(1A)), accept undertakings at any stage up to publication of its report (section 154A), run implementation trials of remedies it is minded to impose (section 161C), and must keep the effectiveness of undertakings and orders under review and act where they have proved ineffective (section 162A).

Market studies and market investigations compared

The two stages differ in who conducts them, how long they take, the threshold the CMA must meet and what it can impose at the end.

Feature	Market study	Market investigation
Who conducts it	The CMA as a single authority	An independent CMA group
Statutory timetable	Twelve months from the launch notice	Eighteen months, extendable by up to six
Threshold	Reasonable grounds for suspecting harmful features	A full adverse effect on competition finding
Outcome	No action, undertakings, or a reference	Binding remedies: orders and undertakings

Remedies the CMA can impose

At the end of an investigation the CMA can impose remedies to achieve, in the words of section 138(4), as comprehensive a solution as is reasonable and practicable to the adverse effect on competition it has found and to any detrimental effects on customers resulting from it. The CMA can impose behavioural remedies, such as conduct restrictions, information disclosure, price controls and access requirements, and structural remedies up to divestiture or the separation of a business. Structural remedies are the most intrusive and the CMA generally prefers behavioural measures where those will achieve the same solution. Once the group has published its report, and until the reference is finally determined, the CMA can accept interim undertakings or make interim orders to prevent pre-emptive action, and where such action has already been taken it can require the position to be restored.

Why market investigations matter for your business

The CMA can reshape a whole market through a market investigation, binding every firm in it, not only a firm accused of wrongdoing. The consequences can be far-reaching, from mandated access and price controls to divestiture, and the CMA must keep its remedies under review, so a business remains subject to them for years after the report. Because the CMA can trial remedies before imposing them and accept undertakings at any stage, a business that engages early can shape the outcome. The CMA can run a market study or investigation alongside, or instead of, its work under the strategic market status regime, particularly in markets it has not designated. Understanding where a study is heading, and what a workable remedy looks like from the inside, is central to protecting a business’s position.

How we work

Bratby Law can be instructed as direct legal advisors on a specific question, as specialist co-counsel alongside a competition or corporate team, and as fractional general counsel on a retained basis. Rob Bratby currently holds four fractional General Counsel appointments, at The One Touch Switching Company, TelXL, Core Communication and the UK Payments Initiative. Where a market inquiry involves personal data, the data protection analysis runs alongside it.

Frequently asked questions about market investigations

What triggers a market study?

The CMA can open a market study where it has concerns about how a market is working, drawn from complaints, super-complaints, its own intelligence or the outcome of other cases. A study is an examination, not an accusation against a particular firm, and it runs to a twelve-month statutory timetable from the launch notice.

Does a market investigation require proof that a firm broke the law?

No. The CMA examines features of a market that harm competition, whether structural or conduct-based, and need not show any intention to harm competition or any breach of a prohibition. That is what distinguishes it from enforcement under the Competition Act 1998, which addresses specific unlawful conduct.

Can the CMA force a company to sell part of its business?

Yes. Structural remedies, including divestiture, are available under Schedule 8, paragraph 13, of the Enterprise Act 2002, given effect by a final order under section 161. They are the most intrusive option, and the CMA generally prefers behavioural remedies where these can achieve a comprehensive solution to the adverse effect on competition it has found.

How does this regime relate to the digital markets regime?

They are complementary. The market investigations regime applies to any market, while the strategic market status regime under the DMCC Act 2024 applies only to designated digital firms. The CMA can use a market study or investigation in markets that are not designated, or alongside its digital markets work, and the DMCC Act 2024 added to the CMA’s Part 4 powers.

How should my business respond to a market study?

Constructively and early. A market study is an information-gathering exercise, and the quality of a business’s evidence and engagement shapes whether the CMA refers the market, accepts undertakings or takes no action. Under the DMCC Act 2024 the CMA can accept undertakings at any stage of a study or investigation. A business that engages early, with a clear account of how the market works and what a workable remedy would look like, can influence the outcome.

Related digital regulation pages

The other digital regulation pages on this site:

Digital Regulation
SMS Designation and Conduct Requirements
Pro-Competition Interventions
Concurrent Competition Powers
Merger Control in Digital Markets
Competition Enforcement and Litigation
EU Digital Markets Act Compliance

Also see

These markets also raise questions in Telecoms Regulation, Payments Regulation and Data Protection. For commentary on current developments, see our Insights.