The need for digital transformation due to the ongoing evolution of digital technologies is impacting business models. With a growing understanding that organizations of any size now can operate multiple business models, the question now arises of how such a business model portfolio is impacted? In our research, we studied digital transformation and the role of digital technologies and data, at legal professional services firms, across their business model portfolios through a multiple case study of three Australian law firms. This study revealed how multiple business models have been evolving organically within these case organizations, along the lines of their traditional professional work types. Technology is further reinforcing these business model changes, and impacting each business model differently. Moreover, digital technologies and data also impact synergies, tensions, and barriers across the business models in the business model portfolio. We conclude that, conscious delineation of digital transformation is necessary to understand and reap the benefits possible from strategically leveraging digital technology and data for each business model and the portfolio. This paper provides valuable empirical insights for both academics and practitioners, into digital transformation using the business model portfolio perspective to understand the differentiated roles of digital technologies and data.