In her PhD thesis, Giulia Aurélie Sonderegger analyses killer acquisitions, which, in short, are acquisitions that aim to pre-empt potential future competition at an early stage. While this phenomenon was originally discovered in pharmaceutical markets, this thesis exclusively discusses killer acquisitions in the context of digital markets, thereby primarily focusing on the current European Merger Control Regulation (EUMR). The main research question is whether the EUMR is appropriate to tackle killer acquisitions occurring in digital markets, and if not, in what ways it needs to be amended to better address the challenges in the future. To tackle this question, the author assesses both the economic and legal effects of killer acquisitions on merger control in digital markets and, based on her findings, suggests amendments to the current European merger control regime. For a more comprehensive analysis, this thesis also includes an assessment of the recently enacted Digital Markets Act (DMA) to ascertain whether this regulation may serve as an additional tool to remedy such transactions.