In the era of inter-industry convergence, abuses of substantial market power by large digital platforms such as Google, Apple, Facebook, and Amazon, and their increasing number of acquisitions towards small- and medium-sized tech-firms suspicious of eliminating potential competitors are recent representative issues in the ICT sector. Alternative competition policies have been discussed to effectively deal with those firms’ anti-competitive behaviors in a changing environment of competition such as a digital platform economy instead of traditional policies. In this regard, we examine the U.S. and EU competition policy responses to ICT firms’ anti-competitive behaviors in order to provide policy implications to our competition authority. According to our case studies, the U.S. and EU competition and legal authorities consider characteristics of the digital platform economy when they conclude whether firm behaviors are anti-competitive. Furthermore, we find that Facebook's acquisition of WhatsApp leads to a tipping effect and harms market competition. Given these results, we suggest that our competition authority has to consider the balance between innovation and competition when they implement competition policies in the era of inter-industry convergence.