This article discusses the formation of an international working group by the US Federal Trade Commission, US Department of Justice, offices of US state Attorneys General, the Canadian Competition Bureau, the European Commission and the UK’s Competition and Markets Authority (CMA) to assess and update their approach to analyzing the effects of pharmaceutical mergers. This is part of the significant trend of global authorities being increasingly joined-up and reflects the importance being placed on pharmaceutical mergers and issues such as innovation competition and “killer acquisitions”, as well as evolving approaches in this regard. The article comments on the likely key implications of this new initiative and also highlights that the CMA’s involvement reflects its higher global profile following Brexit.