Reviewing our approach to assessing merger efficiencies

The CMA has been delivering a programme of work to embed our 4Ps framework – pace, predictability, proportionality, and process – across our merger control function. In October 2025, we published updated guidance on our approach to jurisdiction and procedure, to clarify our approach to jurisdiction and global deals. In December, we published updated guidance on our approach to merger remedies.

We are now launching a review into our approach to the assessment of rivalry-enhancing efficiencies in mergers, as part of our ongoing commitment to support growth, investment, and business confidence across the UK economy.

We are seeking your views and evidence on:

• the CMA’s analytical approach to rivalry-enhancing efficiencies, including the types of evidence we consider and how we assess dynamic efficiencies
• the CMA’s process for assessing rivalry-enhancing efficiencies, including how we engage with merging parties on efficiency claims