Board Diversity and Green Innovation Among Nigerian Manufacturing Firms

The nexus between board diversity and green innovation remains critically understudied in sub-Saharan African emerging economies, particularly in contexts defined by institutional voids and environmental governance deficits. This study investigates the relationship between board diversity—encompassing gender diversity, ethnic diversity, educational diversity, and board independence—and green innovation among 40 listed manufacturing firms on the Nigerian Exchange Group (NGX) over the period 2010–2024. Employing an ex-post-facto research design with balanced panel data comprising 600 firm-year observations, and utilizing pooled OLS, fixed effects, and random effects estimators supplemented by the Hausman specification test, the study finds that gender diversity and educational diversity exert statistically significant positive effects on green innovation, while ethnic diversity demonstrates context-dependent, non-linear effects. Board independence emerges as a significant governance mechanism that amplifies green innovation outcomes. Key control variables—firm size, financial leverage, and ownership structure—yield results consistent with resource-based and agency theory predictions. Post-estimation diagnostics, including the Variance Inflation Factor (VIF), Breusch-Pagan LM test, and the Modified Wald test, confirm the robustness of reported findings. The study contributes original evidence from an under-researched African manufacturing context, offering novel theoretical integration of upper echelons theory, resource dependence theory, and stakeholder theory. Findings carry significant policy implications for the Securities and Exchange Commission of Nigeria (SEC), manufacturing sector regulators, and corporate boards navigating the nexus of sustainability, governance reform, and industrial decarbonization.