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Competition law

Competition law

This page contains the following:

Introduction to competition law

Competition regulators

EU and UK legislation regulating anti-competitive agreements and concerted practices

Relevant market tests

What's new on this topic

Groceries Code Adjudicator

PubCo Code

Restraint of trade at common law

Enforcement of competition law and consequences of infringement

Merger control at EU and UK level


Introduction to competition law

Competition law seeks to protect consumers and business undertakings from the effect of the lack of competition in the provision of goods and services, such as restricted choice, poor quality, price fixing and other inefficiencies.

Although the perception may be that competition law is mainly the concern of large enterprises, in fact the owners and managers of businesses of all sizes need to be aware of the impact of competition law, chiefly for two reasons:

* Even a small or medium sized enterprise (“SME”) may infringe competition law if it has a significant share of the 'relevant market' in goods or services. The sanctions for infringement may be considerable.

* A business adversely affected by unlawful competitive behaviour by a cartel, anti-competive agreements or concerted practices, or by the economic effect of a merger of other enterprises, needs to be aware of competition law, s that it can assert its own rights and protect its position in the marketplace.

Competition law in the widest sense has effect in the following ways:

* common law principles making certain agreements which are in restraint of trade, unenforceable and void;

* legislation regulating anti-competitive agreements and concerted practices, both at UK level and at EU level;

* legislation regulating abuse of a dominant position, again both at UK level and at EU level;

* legislation controlling business takeovers and mergers, again both at UK level and EU level;

* sector specific regulation of economic activity, e.g. telecommunications, energy supply;

* EU competition law regulates 'state aid'

The European Commission monitors and controls state aid in the EU by requiring member states to notify the Commission in advance of proposed state aid in order to ensure compliance.

There are a few exceptions to the notification requirement, namely:
•if your measure falls within the de minimis regulation ie you are giving less than 200,000 euros over 3 fiscal years
•measures which are covered under a pre-existing and approved scheme
•measures falling within the General Block Exemption regulation


Given the purpose of this Site, our aim in this section is to address the aspects of competition law most likely to be of concern to owners and managers of SMEs.

Further reading on general competition law

Competition Law Risk

This short guide has been jointly published with the Institute of Risk Management to help businesses comply with competition law. It provides a basic overview of competition law, outlining the steps businesses and risk professionals can take to help identify and reduce competition law risks. It also outlines what to do if competition law has been breached and provides case studies with key learnings.

EU competition law

The EU Commission provides an overview of EU competition law.

Competition regulators

The EU Commission is responsible for the development of EU competition policy and competition law enforcement.

In the UK, the Office of Fair Trading (OFT) has been responsible for the general enforcement of competition law. However, the new Competition and Markets Authority (CMA) was legally established on 1 October 2013 by the Enterprise and Regulatory Reform Act 2013. The CMA became fully functional on 1 April 2014. The CMA is responsible for:

* investigating mergers which could restrict competition;

* conducting market studies and investigations where there may be competition and consumer problems;

* investigating where there may be breaches of UK or EU prohibitions against anti-competitive agreements and abuses of dominant positions;

* bringing criminal proceedings against individuals who commit the cartels offence under the Enterprise Act 2002;

* enforcing consumer protection legislation under the Consumer Protection from Unfair Trading Regulations 2008 to address practices and market conditions that make it difficult for consumers to exercise choice;

* cooperating with sector regulators and encouraging the regulators to use their competition powers;

* considering regulatory references and appeals and carrying out other competition roles when these powers are transferred from the Competition Commission and the Office of Fair Trading in April 2014.

EU and UK legislation regulating anti-competitive agreements and concerted practices

Competition law derives both from EU legislation and UK common law and legislation. In general terms, EU competition law applies in the case of economic activity affecting trade between EU member states, whereas UK competition law is concerned with economic activity within the UK.

The EU law is derived from Articles 101-102 of the Treaty on the Functioning of the European Union and implementing regulations. UK competition law is based mainly on Chapter 1 of the Competition Act 1998.

EU competition law has an additional dimension as regards 'state aids', i.e. the regulation of financial and other aid which a member state may give to private enterprises which may affect competion between member states. See the EU Commission pages on state aid

EU and UK competition rules apply in parallel to forbid or regulate three main types of economic activity by 'undertakings' (i.e. individuals and legal entities which carry out an economic activity):

* agreements and other forms of co-operation between undertakings which may affect trade between Member States or trade within the UK and which prevent competition;

* abuse by an undertaking of a dominant market position;

* takeovers and mergers of undertakings (see below 'Merger control')

Exempted agreements

At both the EU and UK levels, an agreement may be exempt from the prohibition if it meets certain criteria, i.e.:

* if it contributes to improving production or distribution, or promoting technical or economic progress, while allowing consumers a fair share of the resulting benefit;

* the agreement must not impose on the undertakings concerned restrictions which are not indispensable to the attainment of those objectives, or afford the undertakings concerned the possibility of eliminating competition in respect of a substantial part of the products in question.

The EU Commission and the OFT may grant exemption to a category of agreements. Further, a court may grant exemption if it is satisfied that the above conditions are satisfied.

Relevant market tests

The concept of the "relevant market" is crucial in the application of competition law. In order to assess the economic effect of undertakings' activities, it is neccessary to define the market in which they operate. service.

Market definition provides a framework for competition analysis. For example, market shares can be calculated only after the market has been defined and, when considering the potential for new entry, it is necessary to identify the market that might be entered.

Further guidance is obtainable from:

EU Commission: Notice on the definition of relevant market:

OFT guidance on market share

What’s new on this topic [see What’s new page or archive for full item]:

01/04/2015: Consumer Rights Act 2015

The Consumer Rights Act 2015 (CRA) has extended the jurisdiction of the Competition Appeal Tribunal (CAT). Its jurisdiction is currently restricted. It may hear appeals from decisions of the Competition and Markets Authority (CMA) and other sector regulators with competition powers. It may also hear so-called ‘follow-on’ cases. A party which alleges damage caused by behaviour which has already been found to be in breach of competition laws by the CMA, EU Commission and certain other regulators may bring a follow-on action.

Stand-alone claims: unlike a ‘follow-on’ case, in a ‘stand-alone’ claim, there is no decision by a competition authority on which the party which alleges damage may rely brings the action to prove an infringement. In Enron Coal Services Ltd (in liquidation) v English Welsh & Scottish Railway Ltd, the Court of Appeal ruled that the scope for the CAT to go beyond the findings of the initial infringement decision is extremely limited. This judgment is widely thought to be one of the contributing factors restricting the role of the CAT in competition law actions in the current regime. Businesses or consumers who wish to bring stand-alone cases must bring their case in the High Court of England and Wales, the Court of Session or the Sheriff Court in Scotland or the High Court of Northern Ireland.

Injunctions: whilst the CAT may award damages for follow-on actions, it does not have the power to grant injunctions (an order which prohibits a party from doing a particular act). This restriction prevents a party from obtaining redress from the CAT in the form of an order prohibiting, for example, anti-competitive pricing. At present, a party seeking an injunction would need to apply to the High Court.

Reforms: The CRA provides for follow-on cases to be brought before the CAT and to have the power to grant injunctions. There is also power to allow a fast-track procedure for claims to enable simpler cases brought by small and medium enterprises. In addition, the CRA will introduce enhanced rights for consumers seeking redress for UK or EU competition law infringements. At present, private, representative actions for such infringements can be brought by a specified body in the Competition Appeal Tribunal (CAT), but these can only be brought on an ‘opt-in’ basis ; i.e. a claimant has to choose to be involved in the action. However, only one such collective action has been brought since the relevant provisions were introduced. There are measures to improve the efficacy of the existing ‘opt-in’ provisions, and to introduce a new ‘opt-out’ regime more akin to the US class action system, where a claim is pursued on behalf of a specified class of unnamed claimants, who are deemed included in the action unless they have specifically chosen not to be involved.

12/01/2014: Cyprus Airways ordered to pay back incompatible aid

The European Commission has concluded that a restructuring aid package of over €100 million for Cyprus Airways gave the company an undue advantage over its competitors in breach of EU state aid rules. Cyprus Airways is therefore required to repay all incompatible aid received, which according to the Commission's information amounts to over €65 million plus interest. In particular, the Commission found that Cyprus Airways had no realistic perspective of becoming viable without continued state subsidies.

As a result of the EU decision, Cyprus Airways has initiated its voluntary liquidation.

18/11/2014: Ofcom investigation: Premier League football rights

Ofcom has opened an investigation into how the Premier League sells live UK audio-visual media rights for Premier League football matches. Under the Competition Act 1998 s 25, Ofcom may conduct an investigation where there are reasonable grounds for suspecting there is an agreement which has as its object or effect the prevention, restriction or distortion of competition within the UK and/or the EU.

28/04/2014: CMA publishes guidance on how small businesses can comply with competition law

The Competition and Markets Authority (CMA) has published a guide to help small businesses comply with competition law. The guide focuses on protecting small businesses and consumers from anti-competitive behaviour. The information in the guide provides a basic overview of the law and outlines the steps small businesses can take to comply with the law.

20/03/2014: OFT issues decision in care home medicine cartel case
Hamsard 3149 Limited (Hamsard), its subsidiaries Quantum Pharmaceutical Limited and Total Medication Management Services Limited (trading as Tomms Pharmacy, together with Celesio AG and its subsidiary Lloyds Pharmacy Limited have been found to have infringed competition law by entering into a market sharing agreement in relation to the supply of prescription medicines to care homes in England, following an Office of Fair Trading investigation and a Statement of Objections in January 2014. The OFT imposed a fine of £370,226 on Hamsard and its subsidiaries.

08/01/2014: Nike and Adidas face ‘cartel probe’
The decision by Nike and adidas to supply only to outlets purchasing products to a value of GBP 25,000 has attracted publicity and criticism by some smaller retailers. One retailer is reported to have made a complaint to the OFT.
Comment: competition law may have a bearing on this commercial behaviour but as often is the case in this area, difficult questions arise in relation to the economic analysis and the proper application of competition law.
If there is evidence of the manufacturers acting in collusion, an infringement of the law would be clear and businesses adversely affected would have a right to legal redress. However, if the behaviour is the result of one manufacturer acting on its own, the competition law implications are less clear-cut. In principle, if an enterprise has a ‘dominant position’ in the relevant market, an unreasonable refusal to supply could be grounds for competition law redress under EU and UK law. This may be very difficult to establish; see for instance the decision of the Court of Appeal in 2007 in the case of Attheraces Limited and Anor. v The British Horseracing Board Limited and Anor.

0/10/2013: Competition Commission imposes price control on china clay suppliers
Imerys Minerals Limited and Goonvean Limited Kaolin were concerned in the extraction, processing and supply of kaolin products from deposits and production facilities located in Cornwall. Kaolin, also known as ‘china clay’, is a mineral used in the manufacture of a range of end-products such as sanitary ware (bathroom fixtures like sinks, baths and toilets), tableware, paper products, paints and adhesives (‘performance-mineral applications’), pharmaceuticals (‘life-science applications’), refractory applications, and fibreglass production.

05/08/2013: OFT issues decision in mobility scooters case
he OFT has issued a decision finding that Roma Medical Aids Limited (Roma), a manufacturer of mobility scooters based in Bridgend, Wales, and some of its online retailers, breached competition law. The OFT found Roma entered into arrangements with seven UK-wide online retailers which prevented them from selling Roma-branded mobility scooters online and from advertising their prices online. The OFT found that these practices limited consumers' choice and obstructed their ability to compare prices and get value for money. The practices occurred over various periods in relation to different retailers between 2011 and 2012 and prevented, restricted or distorted competition in the supply of mobility scooters in the UK. The OFT has directed the parties to bring the arrangements to an end (where this has not already happened) and to refrain from entering into the same or similar arrangements in the future. The decision relates to agreements and/or concerted practices which had the object of preventing, restricting or distorting competition in the supply of mobility scooters in the UK by: * prohibiting online sales by certain retailers in various periods between July 2011 and April 2012 in respect of Roma-branded mobility scooters, and * prohibiting online advertising by certain retailers of any prices in various periods between July 2011 and April 2012 in respect of Roma-branded mobility scooters.

25/07/2013: Challenge to EU Commission decision on De Beers sightholder agreements fails
The Diamond Trading Co. Ltd (‘DTC’) is part of the De Beers group of companies, the largest producer of rough diamonds in the world. DTC operated a system of supply agreements with customers known as ‘sightholders’ who had exclusive rights to purchase rough diamonds under the 'Supplier of Choice' (SOC) system. DTC notified to the European Commission in 2001 the set of standard sightholder agreements in order to obtain ‘negative clearance’ or alternatively an exemption for the SOC system from the EU law against anti-competitive agreements in what was then article 81 of the EU Treaty. After initial objections by the EU Commission on the grounds that the system amounted to anti-competitive agreements and abuse of a dominant position which infringed articles 81 and 82 of the Treaty, De Beers proposed various changes to the SOC agreements and in 2003, the Commission closed the procedure by means of a ‘comfort letter’.In 2005, Diamanthandel A. Spira BVBA (‘the applicant’) filed a complaint against De Beers SA (established in Luxembourg) and DTC, alleging that the SOC system introduced by them had constituted an infringement of arts 81 and 82 EC and, the applicant requested that the Commission EU reopen the proceedings concerning SOC. After a long series of exchanges of correspondence and proceedings before the General Court of the EU, the Commission confirmed its rejection of the applicant's complaint, on the grounds that competition between downstream operators was not sufficiently distorted to justify further investigation, since there had been a sufficient number of sources of supply for which those operators could compete.In 2007, the applicant applied to the General Court for annulment of the Commission’s rejection of its complaint on various procedural grounds. In July 2013, the Court dismissed the applications
.[Note: the above is a brief summary; reference should be made to the full text of the judgment of the European Court of Justice]

Groceries Code Adjudicator

The Groceries Code was introduced in 2010 by the Competition Commission following the 2009 Competition Commission investigation. The Groceries Code obliges the large retailers to deal fairly and lawfully with their suppliers on areas including: unilateral variations to supply agreements; compensation payments for shrinkage/wastage/retailer forecasting errors; allowing suppliers to choose their on suppliers for things such as haulage and packaging.

The Groceries Code does not cover issues such as: price setting; relationships between indirect suppliers to the supermarkets; food safety and labelling; and the Voluntary Dairy Code or horsemeat mis-labelling.

The Groceries Code Adjudicator was established under the  Groceries Code Adjudicator Act 2013 to rule on and enforce the Groceries Code. It is the UK’s first independent adjudicator to oversee the relationship between supermarkets and their suppliers. It ensures that large supermarkets treat their direct suppliers lawfully and fairly, investigates complaints and arbitrates in disputes.

The Groceries Supply Code of Practice defines groceries as:

food (other than that sold for consumption in the store), pet food, drinks (alcoholic and non-alcoholic, other than that sold for consumption in the store), cleaning products, toiletries and household goods.”

The definition does not include:

“petrol, clothing, DIY products, financial services, pharmaceuticals, newspapers, magazines, greetings cards, CDs, DVDs, videos and audio tapes, toys, plants, flowers, perfumes, cosmetics, electrical appliances, kitchen hardware, gardening equipment, books, tobacco and tobacco products.”

The Groceries Code is only concerned with direct supplies of groceries to one of the listed retailers, namely:

* Asda Stores Limited, a subsidiary of Wal-Mart Stores Inc
* Co-operative Group Limited
* Marks & Spencer plc
* Wm Morrison Supermarkets plc
* J Sainsbury plc*
* Tesco plc
* Waitrose Limited, a subsidiary of John Lewis plc
* Aldi Stores Limited
* Iceland Foods Limited, a subsidiary of the Big Food Group
* Lidl UK GmbH

What’s new item on this topic [see What’s new page or archive for full item]:

08/02/2014: Groceries Code Adjudicator guidance: on shelf position charging
Tthe Adjudicator has published a letter on the GCA website to serve as guidance supporting interpretation of the GSCOP. The view of the Adjudicator’s view that to ask for such payment is contrary to the spirit, if not the letter, of the GSCOP, and is effectively a requirement. This is because a supplier would infer from such a request that unless they agreed to it, they would suffer some detriment. In this case, Tesco has assured the Adjudicator that its buyers had been reminded that the Code did not permit payments to be requested in this way; and it had informed all the affected suppliers that the request was rescinded.

PubCo Code

For information about the PubCo Code, see: Public house

Restraint of trade under common law

English common law has developed through a series of decided cases the general principle that a person is entitled to exercise any lawful trade or calling as and where he wishes, and any restrictions are unenforceable unless they are strictly necessary to protect a legitimate business interest, and are not unreasonable in the public interest or in the interests of the parties.

The principle extends to economic activity beyond the ordinary meaning of the word 'trade', and may include contracts restricting the way in which a tradesman carries on his business on a piece of land, and to restraints imposed by the rules or practices of professional or other bodies controlling particular activities.

Although the importance of the common law in this area has diminished  following statutory regulation, the common law principles are still relevant in the folowing areas:

* Post-employment restrictions in employment contracts;

* Non-compete restrictions in agreements for the sale of a business, franchise agreements and joint ventures.

A contractual undertaking not to trade is void and unenforceable against the promisor as contrary to the public policy of promoting trade, unless the restraint of trade is reasonable to protect the interest of the purchaser of a business. The leading case is Nordenfelt v Maxim, Nordenfelt Guns and Ammunition Co [1894] AC 535.

Agreements which are caught by the above principles are treated in English law as void and therefore unenforceable as between the parties. However, they are not unlawful in the sense that third parties may take action against them even if affected by the agreement, in contrast to the position under modern anti-competition legislation.

09/07/2014: Court rules on remedy for breach of non-compete clause by sellers of business

One Step (Support) Limited v Garner and Garner
[2014] EWHC 2213 (QB)

In this case, the claimant company purchased a business from the defendants who agreed not to compete with the business sold and not to solicit customers for a certain period.

The High Court ruled found that the defendants had breached the non-competition and non-solicitation clauses. The question arose as to what remedy the claimant company was entitled to.

Enforcement of competition law and consequences of infringement

Infringement of the law may lead to severe civil law sanctions and, in the UK, criminal law in certain circumstances, both on the undertaking itself and on its directors. Measures which can be taken include:

Regulatory enforcement

* Investigations: both the EU Commission and the OFT have extensive powers of investigation including the ability to carry out without notice compulsory searches at business premises and inspect and take away documents (so-called “dawn raids”).

* Fines: Undertakings may be fined an amount up to 10% of group world turnover.

* Criminal sanctions: in the UK, serious infringements of competition law such as operating cartels may lead to disqualification of directors and fines or even imprisonment of directors and other individuals concerned.

Civil enforcement by private action

* Invalidity of agreements: provisions in agreements which breach competition law are void and unenforceable.

* Third party legal action: undertakings in breach of competition law may be liable to actions for damages from customers and competitors who can show they have suffered damage arising from the infringement.

* Prohibition of takeovers and mergers: undertakings may be prohibited from proceeding with a takeover or merger or, if the transaction has already completed, undertakings may be required to dispose of undertakings acquired; see below.

As noted above, agreements which are caught by the English common law principles as in restraint of trade are void and therefore unenforceable as between the parties. However, they are not unlawful in the sense that third parties may take action against them or claim compensation even if affected by the agreement, in contrast to the position under anti-competition legislation.

EU law competition legislation and jurisprudence provides for persons affected by anti-competitive conduct to have an enforceable civil right to claim compensation. However such legal action is fraught with difficulty. EU legislative measures are due to be enacted to enhance this right.

On 17 December 2014, the European Commission opened a public consultation on proposed changes to its antitrust procedures in order to align them with the Directive regarding damages actions by victims of antitrust violations. Comments can be submitted until 25 March 2015. Commission adopts amendments to Regulation 773/2004 and four related Notices. On 3 August 2015, the European Commission announced it had adopted amendments to Regulation 773/2004 and four related Notices (Access to the File, Leniency, Settlements, Cooperation with National Courts), aimed at aligning them with Directive 2014/104/EU on Antitrust Damages Actions.The Directive was adopted at the end of 2014 by the European Parliament and the Council, based on a Commission proposal. Member States have to implement the Directive by 27 December 2016. The Directive has two objectives: to ensure that victims of antitrust violations can effectively claim damages (through actions before national courts, or out of court); and to optimise the interrelation between such private actions and public enforcement by the Commission and national competition authorities. To achieve the second objective, the Directive, amongst other things, prohibits the use of leniency corporate statements and settlement submissions before national courts and limits the use of documents created specifically for the purpose of a competition authority's investigation until after the investigation is closed.

In order to ensure an effective protection of these documents in Commission investigations, the Commission adapted the provisions in Regulation 773/2004 and the four Notices concerning the disclosure and use of information in the Commission's investigative file to the Directive's rules on disclosure and use of information obtained from competition authorities in antitrust damages actions. Furthermore, basic concepts of the Commission's leniency and settlement programmes are introduced into hard law, i.e. Regulation 773/2004. Finally, the Notice on Access to the File determines that documents from the file unrelated to the investigation can be returned to the parties.


Under UK competition law, where a business undertaking has been found to infringe competition law by the Competition and Markets Authority or the Competition Appeals Tribunal (CAT), another business undertaking which claims to have been adversely affected by the infringement may claim monetary compensation before the CAT by way of a so-called ‘follow-on’ case [Competion Act 1998 s. 47A]. The CAT's jurisdiction has now been extended by reforms introduced by the Consumer Rights act 2015, whereby business undertakings may bring ‘stand-alone’ cases before the CAT, i.e. cases where no prior infringement decision has been made against the party whose actions are the subject of complaint (see What’s new on this topic).

16/07/2014: Wurst luck for German sausage cartel

The Guardian has reported (16 July 2014) that German sausage makers have been fined €338 m (£267 m) for price fixing. The so-called “Atlantic group” (named after the hotel Atlantic in Hamburg where the manufacturers first met), is said to have been fixing the price of sausages for decades by Germany’s competition regulator, the Bundeskartellamt (Federal Cartel Authority) (Bka).

Merger control

EU merger control

EU merger control law derives mainly from Article 101 of the Treaty on the Functioning of the European Union and Council Regulation (EC) No 139/2004 of 20 January 2004 on the control of concentrations between undertakings (the EC Merger Regulation).

The European Commission oversees the merger control regime or regulation of so-called 'concentrations' which have a 'Community Dimension'. A concentration has a Community dimension, if:

* the combined aggregate worldwide turnover (from ordinary activities and after turnover taxes) of all the undertakings concerned (in the case of the acquisition of parts of undertakings, only the turnover relating to the parts which are the subject of the concentration shall be taken into account with regard to the seller(s)) is more
than EUR 5,000 million (special rules apply to banks); and

* the aggregate Community-wide turnover of each of at least two of the undertakings concerned is more than EUR 250 million, unless each of the undertakings concerned achieves more than two-thirds of its aggregate Community-wide turnover within one and the same Member State.

In case these thresholds are not met a concentration has nevertheless Community dimension, if:

* the combined aggregate world-wide turnover of all the undertakings concerned is more than EUR 2,500 million; and

* in each of at least three Member States, the combined aggregate turnover of all the undertakings concerned is more than EUR 100 million; and

* in each of at least three Member States included for the purpose of the second point above, the aggregate turnover of each of at least two of the undertakings concerned is more than EUR 25 million; and

* the aggregate Community-wide turnover of each of at least two of the undertakings concerned is more than EUR 100 million,

unless each of the undertakings concerned achieves more than two-thirds of its aggregate Community-wide turnover within one and the same Member State.

As a general rule, mergers that fall under the scope of the EU Merger Regulation are excluded from review under the UK merger control legislation - se below.

Further reading: EU merger regulation

UK merger control

The Enterprise Act 2002 (EA) replaced the former merger regulation in the Fair Trading Act 1973. Further significant changes were made by the Enterprise and Regulatory Reform Act 2013.

As a result of these changes, decisions on merger control are in general taken by the Competition and Markets Authority (CMA) which took over the functions of the former Office of Fair Trading (OFT) and the Competition Commission, rather than the Secretary of State; and mergers are assessed against a pure competition test, rather than the wider public interest test which formerly applied.

Special arrangements apply in the case of media mergers, water and sewerage undertakings and special public interest cases.

Merger situations

A merger must meet all three of the following criteria to constitute a relevant merger situation for the purposes of the EA:

1. Either two or more enterprises must cease to be distinct, or there must be arrangements in progress or in contemplation which, if carried into effect, will lead to enterprises ceasing to be distinct.

2. Either the UK turnover associated with the enterprise which is being acquired exceeds £70 million (‘the turnover test’) or the enterprises which cease to be distinct supply or acquire goods or services of any description and, after the merger, together supply or acquire at least 25% of all those particular goods or services of that kind supplied in the UK or in a substantial part of it; the merger must also result in an increment to the share of supply or acquisition (‘the share of supply test’).

3. Either the merger must not yet have taken place, or it must have taken place not more than four months before the day the reference is made, unless the merger took place without having been made public and without the CMA being informed of it (in which case the four-month period starts from the earlier of the time the merger was made public or the time the CMA was told about it). The four-month deadline may be extended in certain circumstances.

Generally, mergers are prohibited, or remedies required, if they would result in a substantial lessening of competition in a UK market.

For further detail, see UK merger control.

Further reading: CMA Merger Guidance

[Page updated: 30/01/2017]