Abstract Low-carbon innovation is necessary to overcome the delay of governments in implementing the Paris agreement. However, large institutional investors only engage in climate risk management. They cannot commit to low-carbon innovation because that is fundamentally uncertain, short-term unprofitable, and their index-tracking strategy is incompatible with screening firm-specific breakthroughs. To pursue sustainable corporate governance, institutional investors should rather tie their hands with controlling shareholders. Controlling shareholders can contribute their entrepreneurial vision to low-carbon innovation while institutional investors allow them to scale this vision. This article argues that institutional investors catering to the preferences of climate-conscious beneficiaries should finance controlling shareholders through conditional dual-class shares. Dual-class shares allow relaxing the financial conditions for control. To fulfil their mandate from climate-conscious beneficiaries, institutional investors can outcompete short-term profit-seeking investors by offering controlling shareholders a higher wedge between voting rights and economic interest and the possibility to cash in higher idiosyncratic private benefits of control, if successful, conditional on engaging in low-carbon innovation. Having at stake welfare-increasing private benefits of control, as well as all or most of their wealth, controlling shareholders are incentivized to discover low-carbon breakthroughs or to acknowledge failure to do so. Corporate law should facilitate contracting between controlling shareholders and institutional investors to support this incentive. Target-contingent transfer sunsets should allow cashing in control premiums only if the low-carbon innovation succeeds. Divestment sunsets and other contractual safeguards should prevent controlling shareholders from increasing agency cost, without undermining equity capital raising. Dual-class recapitalizations should be allowed with a majority-of-minority vote.