The purpose of this study is to develop a typology framework for M&A activities in digital platform ecosystems to systematically understand the motivations and the strategies of acquirers. Unlike traditional firms, digital platform firms co-create value through networks by building an ecosystem of autonomous agents, and to understand their M&As, it is necessary to look at them holistically from a platform ecosystem perspective. The literatures predominantly focused on policy discussions such as competition authorities' antitrust regulation and consumer welfare issues, and do not include the platform ecosystem perspective. In addition, the perspective of the literatures on M&A is mainly focused on the technical resources of the acquired firm. Therefore, this study presents four types of M&A activities of acquirers in digital platform ecosystems into four types: internalization of technological resources, diversification of products and services, extension of core competencies, and strengthening of market dominance, based on two dimensions of the level of autonomy of the acquired firm and the resources possessed by the acquired firm(technological or market resources). 126 cases of M&As over the period 2017-2021 of Korea's leading digital platform firms, Kakao and Naver, were applied to the framework. The typological analysis resulted that Kakao was most active in the ‘extension of core competencies’(49.5%) and Naver in the ‘internalization of technological resources’(45.2%). This study propose a methodology for systematic understanding of M&A behavior among platform owners and startups operating in the digital industry and suggest both academic and practical implications.