Private regulation by dominant firms and the digital infrastructure of democracy controlled by some firms constitute the areas where the separation of powers principle, envisaged in a broad sense, and antitrust may share much common ground. A single dominant digital firm may adopt private regulation affecting an entire industry and even society at large, be an important part of the digital infrastructure of democracy and, through many means including lobbying, exercise a significant influence on public decision-makers. Such a firm concentrates an immense amount of politico-economic powers. At the same time, it is subject to antitrust laws and relevant from a contemporary and prospective separation of powers’ viewpoint. Antitrust could, in the end, contribute to the separation of powers in the digital era and, ultimately, to trust. Antitrust for trust, or the ultimate apparent antitrust paradox.

The contribution of antitrust de lege lata to the separation of powers is rather limited. A role should nevertheless be granted to specific legislation, regulation or practices and, possibly, antitrust de lege ferenda, especially with respect to the control of the digital infrastructure of democracy, the prohibition of distortions of the electoral and democratic process, the conclusion of certain governmental contracts with large or, a fortiori, dominant platforms, as well as the regulation and deconcentration or decentralization of artificial intelligence and the Metaverse. Artificial intelligence and, notably, machine learning based on data face a cycle of concentration accentuating the need for regulation. Deconcentration or decentralization may be envisaged, imposed or incentivized. Furthermore, limits are especially necessary when substantial autonomous powers are granted to forms of artificial intelligence. The Metaverse, for its part, may reshape society, politics, and economy around the globe in the future. From an antitrust perspective, the Metaverse poses at least two main issues: antitrust on the Metaverse and antitrust in the Metaverse.