AI and blockchain innovations are rebuilding financial infrastructure and regulation. This Element proposes novel regulatory solutions.

This Element provides an overview of FinTech branches and analyzes the associated institutional forces and economic incentives, offering new insights for optimal regulation. First, it establishes a fundamental tension between addressing existing financial inefficiencies and introducing new economic distortions. Second, it demonstrates that today's innovators have evolved from pursuing incremental change through conventional Fin-Tech applications to AI × crypto as the fastest-growing segment. The convergence of previously siloed areas is creating an open-source infrastructure that reduces entry costs and enables more radical innovation, further amplifying change. Yet this transformation introduces legal uncertainty and risks related to liability, cybercrime, taxation, and adjudication. Through case studies across domains, the Element shows that familiar economic tradeoffs persist, suggesting opportunities for boundary-spanning regulation. It offers regulatory solutions, including RegTech frameworks, compliance-incentivizing mechanisms, collaborative governance models, proactive enforcement of mischaracterizations, and alternative legal analogies for AI × crypto.