Surviving the broad axe: The UK class action regime is alive and kicking, but what can the Supreme Court’s judgment in Merricks/Mastercard tell us about the role of economics in class certifications going forward?

On the 11th December 2020, the UK Supreme Court (“SC”) handed down its judgment in the case between Walter Hugh Merricks, CBE (“Merricks”) and Mastercard Incorporated (“Mastercard”).1 The judgment concerns Merricks’ Collective Proceedings Order (“CPO”) application to pursue a class action for follow-on damages against Mastercard for £14 billion (after interest), on behalf of 46.2 million people.2 The application was originally rejected by the UK Competition Appeal Tribunal (“CAT”) in 2017, before the CAT’s ruling was overturned on appeal by the Court of Appeal (“CoA”) in 2019.3 Mastercard then appealed the CoA’s decision before the SC, but was unsuccessful, with the SC sending the case back to the CAT for re-consideration.

This brief expands on this and other important economic considerations that arise from the SC judgment, including how failing to interrogate a claimant’s proposed damages estimation methodology in sufficient detail is liable to cause serious issues at trial.