History. 10 of 10: banned in the final report at Knauf 2004, BOC 2008, AkzoNobel 2012 and Sabre 2020; the firms gave up at Clariant 2016, Experian 2018, Illumina 2019, Prosafe 2020, YPO 2020 and Crowdcube 2021; none cleared. Each ended within the deadline in force, extensions included.
Hunch. Since the government asked the CMA in May 2025 to weigh investment, none of the six full merger reviews it has closed ended in a ban.
The blocked-or-dropped market resolves YES if by 23:59 London time on 2 March 2027 the CMA's final report blocks nexfibre's purchase of Substantial in full, or the firms give the deal up and the CMA closes the review or the sale contract is ended; clearance with or without conditions, a partial block or no final step by then resolves NO. It resolves on the CMA case page, confirmed by The Guardian or The Independent, which decide together if the page does not open.
We looked for cases where the UK competition regulator, in a full review of a merger not yet completed, found harm to competition, rejected the firms' claimed benefits and named only a ban as a working fix. We found ten such deals from 2004 to 2021. Until 2014 the regulator was the Competition Commission, after that the CMA. (CMA; CMA; GOV.UK)