Answer ... The impact of Brexit on the UK cartel enforcement regime is yet to be seen. In its July 2018 White Paper, the UK government indicated that it will maintain current antitrust prohibitions alongside strong cooperation with EU competition authorities. In a speech in May 2018, Competition and Markets Authority (CMA) Executive Director Michael Grenfell reiterated that Brexit poses significant challenges for competition law enforcement, including an increase in caseload and requirements for further funding. He also noted that there was an uptick of over 35% in competition enforcement activity by the CMA between 2013 and 2018. The CMA’s 2018–19 Annual Plan also notes that it is keen to take on a bigger role on the world stage post-Brexit, including maintaining national jurisdiction over the larger and more complex cases that were previously under the EU’s exclusive jurisdiction.

In September 2018 the UK government published guidance on the application of competition law in the event of a ‘no-deal’ Brexit, stressing that short-term changes will be minimal. However, both this guidance and commentators note that in a ‘no-deal’ scenario, businesses may face a ‘jurisdiction vacuum’, with no agreement on jurisdiction for live antitrust and merger investigations with effects on UK markets. Furthermore, the extent to which UK courts will continue to look to EU court judgments is still unknown; some have suggested that the absence of a ‘single market imperative’ may mean that occasions will arise where the United Kingdom seeks to be more innovative as regards competition policy (eg, in relation to fast-moving digital markets).

In March 2019 the CMA published “Guidance on the functions of the CMA after a ‘no deal’ exit from the EU”. The guidance explains how the United Kingdom will operate as a standalone competition regime after a no-deal exit from the EU. The most significant change would be the end of the one-stop shop principle and that anti-competitive behaviour could be subject to parallel enforcement action by both the European Commission and the CMA. The CMA (or concurrent regulator) will be able to rely only on its powers under the Chapter I prohibition and will no longer be able to apply Article 1 of the Treaty on the Functioning of the European Union, subject to certain transitional rules concerning investigations already being carried out before the United Kingdom’s exit from the European Union.