Political economists have long acknowledged the importance of funded pensions acting as catalysts for processes of financialization. The transformation from rule- to risk-based pension fund governance is particularly important for pension financialization. Risk-based governance involves monitoring of internal decision-making procedures by new professionals rather than compliance with highly detailed legal restrictions. Scholars of financial regulation have termed this kind of supervision ‘regulation from the inside’. Being part of the organization they monitor, internal regulators hold fundamentally ambivalent positions. Existing studies emphasize the duality of internal regulators’ role perceptions as well as their attempts to span the boundaries between themselves and other organizational actors. In this paper, we extend scholarly insights on risk-based supervision of private (non-)financial institutions to pension institutions by focusing on a peculiar form of ‘regulation from the inside’: so-called internal supervisors in Dutch occupational pension funds. Internal supervisors are pension fund functionaries, responsible for evaluating the governing board's performance and holding the board accountable. We report findings from an original survey and interview study among internal supervisors. Contrary to the formal requirement of independence between governing board and internal supervision (a ‘checks and balances’ perspective), we find that internal supervisors often adopt a ‘fusion of powers’ approach that emphasizes collaboration with the governing board. We attribute this finding not only to internal supervision’s institutional design but also to the highly networked character of Dutch pension governance.