Fintech firms, once perceived as “disruptors” of the traditional banking industry, are now increasingly seen as attractive partners for established financial institutions. Partnership arrangements between banks and new financial technology startups have therefore mushroomed over the last several years. Such partnership agreements, which come in different forms and contexts, are usually advantageous for both sides: banks may ordinarily suffer from legacy issues and cumbersome internal processes, and therefore benefit from fintech firms’ superior technology to develop new business ideas. At the same time, a bank’s broad customer base may allow a startup to benefit at an earlier stage from economies of scale and facilitate market entry, while fintechs may also enjoy reputational spill-overs from partnering with an established institution. Most of these arrangements share the goals of outsourcing key banking functions and facilitating market entry for new market players while overcoming relatively tough regulatory hurdles. Yet such arrangements, while generally to be welcomed, pose a number of regulatory problems, in particular concerning the effective supervision of fintechs that operate outside of the direct purview of regulatory authorities. Our recent article “Bank-Fintech Partnerships, Outsourcing Arrangements, and the Case for a Mentorship Regime” [1] explores the implications of a growing number of bank-fintech partnerships for the regulatory framework concerning financial institutions. The various types of partnership arrangements include banking-as-a-service and software-as-a-service frameworks, white-label banking, and front-end neobanks. From a regulatory perspective, all of these arrangements fall under the rubric of “outsourcing” arrangements, where regulated entities outsource some of their functions to third parties, be they regulated or unregulated. The present practice and the relevant regulatory framework raise doubts about the effective supervision of fintechs that operate outside of the direct purview of regulatory authorities. The key downside of the existing collaboration arrangements between banks and fintechs lies in the point that a contractual agreement between the two market participants is a poor substitute for effective regulatory scrutiny. Questions of enforcement and effective supervision emerge, which may ultimately result in problems regarding market stability and systemic risk. The recent downfall of Wirecard [2], the German payments group that relied on partnering with firms in its Asian markets, put a spotlight on the frailty of such arrangements. To address these problems, a number of regulatory tools have been put forward, in particular with the objective of facilitating fintechs’ entry into the supervisory perimeter. However, these initiatives are imperfect. For instance, regulatory sandboxes are geared more towards creating and stimulating [continua..]