The US DOJ facilitated a Merger Case Workshop for the ASEAN competition authorities as a continuation of a series of workshops, with the first Merger Investigation Workshop held virtually on March 2021. The Workshop which was held from 1-2 July 2021 deliberated on the various techniques used to define the relevant markets and to measure the effects of the merger were considered. The participants noted the USDOJ’s approach to assess the effects of mergers based on evidence derived from competitors, customers and the merging entities. The use of IT Forensic Tools was also discussed to gather evidence.