CELLTRION, well-known for its product called Ramsima, is a leading bio venture company in Korea. In order to achieve its vision of a global pharmaceutical company, CELLTRION has continued to do challenges and make innovations. In this case, we looked at the evolution that CELLTRION has taken since its inception, focusing on entering new businesses, generating financial performance, and sustaining growth. Most of all, this case embodies the characteristics of CELLTRION around the business subject, the business environment, the business resources, and the corporate mechanisms that are interactions between subject, environment, and resources. Specifically, this case describes CELLTRION's entry into the CMO business, into the Bio-similar business, and into the Bio-better business. In particular, this paper examined how CELLTRION has repeatedly changed its strategy, organization, and management activities in the process of entering and deepening the global market. This case will provide meaningful implications for prospective entrepreneurs who are trying to start up their own businesses and managers of venture companies seeking to achieve scale-up. In addition, this case could also help managers of established companies who are agonizing over the sustainability of competitive advantages.