Financial companies are increasingly leveraging financial technology (fintech) to monopolize financial data, ostensibly to maximize profit for their clients and enhance their power in society. This trend both exposes the serious limitations of individual consent models of data protection and undermines the nature of financial data as a shared resource by excluding data contributors from its governance. This chapter posits that consumer associations, acting as data trusts, can play a crucial role in overseeing financial data-opolies while fostering the development of the community governance of data. Beyond addressing privacy harms, these associations can promote the attainment of important social goods, including the prevention of predatory and discriminatory lending and the expansion of access to financial capital. By leveraging and shaping both formal and informal rules-in-use that may facilitate these efforts, consumer data trusts can ultimately enhance the legitimacy of financial data commons. A discussion of BlackRock’s Aladdin platform and a European consumer association’s lawsuit against Meta illustrates the argument.