Call for evidence outcome

Reviewing our approach to assessing merger efficiencies

• From: Competition and Markets Authority
• Published: 15 January 2026
• Last updated: 3 June 2026
  Show all updates

  1. 3 June 2026

     Responses published

  2. 15 January 2026

     First published.

This call for evidence has closed

Detail of outcome

The CMA consulted on draft revised guidance on our approach to assessing rivalry-enhancing efficencies in merger cases.

Taking into account the feedback to that consultation, we published updated merger assessment guidelines which incorporate our final revised efficiencies guidance.

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Original call for evidence

Summary

The Competition and Markets Authority (CMA) invited views on its approach to assessing rivalry-enhancing efficiencies in mergers.

This call for evidence ran from
10am on 15 January 2026 to 5pm on 26 February 2026

Call for evidence description

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
• process for assessing rivalry-enhancing efficiencies, including how we engage with merging parties on efficiency claims

Documents

Call for evidence

PDF, 176 KB, 11 pages

AlixPartners

PDF, 251 KB, 11 pages

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Balanced Economy Project

PDF, 247 KB, 3 pages

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BRG

PDF, 206 KB, 6 pages

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Centre for Competition Policy

PDF, 144 KB, 17 pages

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City of London Law Society

PDF, 357 KB, 11 pages

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Clifford Chance LLP

PDF, 234 KB, 9 pages

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Compass Lexecon

PDF, 269 KB, 7 pages

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Econic Partners

PDF, 435 KB, 7 pages

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ELIG Gürkaynak Attorneys at Law

PDF, 429 KB, 9 pages

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Freshfields LLP

PDF, 354 KB, 22 pages

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Friday Initiatives

PDF, 111 KB, 4 pages

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Frontier Economics

PDF, 525 KB, 22 pages

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Herbert Smith Freehills Kramer LLP

PDF, 179 KB, 7 pages

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International Center for Law & Economics

PDF, 292 KB, 13 pages

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Linklaters LLP

PDF, 349 KB, 8 pages

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Paul Weiss

PDF, 426 KB, 14 pages

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PricewaterhouseCoopers LLP

PDF, 394 KB, 14 pages

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Professor Carmine Ornaghi

PDF, 187 KB, 3 pages

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RBB Economics

PDF, 343 KB, 9 pages

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The Computer & Communications Industry Association

PDF, 321 KB, 6 pages

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UK Finance

PDF, 275 KB, 5 pages

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UK Private Capital

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VodafoneThree

PDF, 125 KB, 3 pages

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