So what does this judgment mean for deal-makers in practice?
Appeals of CMA merger decisions remain limited to judicial review grounds: and the so-called high bar in that respect remains. Whilst we don't expect the floodgates to open on successful challenges to CMA merger reviews as a result of this case (and it is worth remembering that the CMA's prohibition decision in this case was ultimately upheld), the Court of Appeal's judgment does provide important guidance for parties (and third parties with jurisdiction) in seeking to challenge CMA merger decisions. The judgment is also timely given, post-Brexit and with the incoming new merger control thresholds under the DMCC Act, the CMA has jurisdiction over a wider range of, and more complex, merger cases and is expected to engage with increasingly complex evidence and theories of harm.
In short, the judgment endorses the CAT's engagement with the evidential underpinning of merger cases: as a result, parties seeking to challenge CMA decisions, and the CAT itself, should find encouragement within the judgment to engage in (perhaps more robust levels of) evidential review going forward.
The guidance provided around the degree of deference to be accorded to the CMA being "fact and context specific" will no doubt be considered carefully by parties seeking to encourage the CAT to engage to a greater extent with the CMA's factual analysis in a given case. Disputes over the interpretation afforded to evidence by the CMA (in particular given the CMA's reliance on parties' internal documents) is also likely to be heavily debated in contested cases.
Cérélia is seeking to appeal onwards to the UK Supreme Court, a rare occurrence in merger control cases.