Facebook’s proposed cryptocurrency, Libra, and its payment system, Novi, pose antitrust challenges and opportunities. By stepping into the financial arena, Facebook raises questions about whether antitrust scrutiny is available at all to review this expansion, and whether the right legal tools exist to protect competition in digital markets. An analysis of Facebook’s position in social media and online advertising reveals the economic value of data, how Libra and Novi can contribute to further market concentration, and how antitrust law has a unique opportunity to demonstrate that it is able to reconcile innovation with competition.