Does one-share-one-vote accelerate ESG price discovery by easing trading and information frictions?

Understanding how sustainability disclosure is reflected in capital-market outcomes remains important for regulators, investors and researchers, especially in Europe, where ESG reporting expectations are comparatively advanced. Yet prior evidence is less clear on whether voting-rights design, particularly one-share-one-vote (1S1V), conditions the association between ESG disclosure and market outcomes in highly liquid firms. Using a 2010?2023 firm-year panel of STO XX Europe 600 constituents and LSEG/Refinitiv ESG scores, we estimate firm and year fixed-effects models with dependence-robust inference to relate next-year quoted bid?ask spreads and annualised volatility to lagged ESG measures and their interaction with equal voting. Higher ESG disclosure is not reliably associated with narrower next-year quoted spreads; the coefficients are economically small and remain so across alternative variance estimators and spread transformations. By contrast, volatility is governance-contingent: among unequal-voting firm-years, higher ESG scores are associated with higher subsequent volatility, whereas the ESG ? equal-voting term offsets this tendency, making the implied association under 1S1V close to zero. Pillar analyses indicate that this moderation is most evident for governance-related disclosure, while environmental and social pillars show limited comparable evidence. The findings identify voting-rights architecture as a boundary condition for ESG?market outcome associations in large-cap European firms.