The impact finance market has sought to 'internalise externalities and adjust risk perceptions' (G20 Green Finance Study Group, 2016), demonstrating the private sector's capability in resolving the climate free-rider problem through the 'greening' of economic activities, partially bypassing corrective government intervention. As the market continues to develop, however, the voluntary disclosure regime that the market operates under threatens to enforce an adverse selection problem and contribute to a fundamental erosion of confidence in the market segment, constraining the potential of impact finance instruments to affect positive social and environmental change. I relate the work of Crawford and Sobel (1982); Milgrom (1981); Verrecchia (1983); Jung and Kwon (1988); Myers and Majluf (1984); Frantz (1997); Frantz and Instefjord (2006) to the green bond market and draw inferences to inform recommendations for policy-led solutions.