The debate surrounding ‘big tech’ and antitrust has dominated public policy discourses over the past few years in many parts of the world. Noteworthy is that several countries and regions, including China, the European Union, and the United States, have launched investigations into the allegedly anticompetitive and exclusionary business practices of companies such as Amazon, Apple, Facebook, and Google and their Chinese counterparts, Alibaba and Tencent. This paper builds on the renewed interest in the topic and discusses in detail – (...) and from an ordoliberal perspective – the key characteristics of the digital economy, the business conduct of tech platforms, and the corresponding antitrust concerns, as well as possible reform steps which could help to strengthen modern-day competition law and policy (and antitrust enforcement). (shrink)