While the consideration of diversity in the board selection process has become an increasingly prominent focus among corporate governance practices, the factors driving how firms define and implement diversity remain contested. Using the annual proxy statements (DEF 14a) of publicly traded companies, this research project explores how board diversity and diversity disclosure practices have evolved over the past three decades, with a focus on the sociopolitical pressures behind this evolution, the difference in industries’ approaches to DEI, and the types of “diversity” corporations employ.

Through comparing corporate trends in diversity with the growth of social movements and punitive legal measures related to discrimination, our findings suggest that legal and sociopolitical forces functioned as powerful drivers for the increase in board diversity practices. Furthermore, business-to-business industries unexpectedly incorporated diversity as a consideration in the board election process more than business-to-consumer industries.

Finally, across-time, firms have shifted from non-identity based definitions of diversity, like diversity of experience, to more identity-focused definitions like race and gender, excluding the year 2025. Taken together, this research provides critical insight into contextualizing the changing approach of corporations to board diversity as an increasingly identity-based, dynamic response to broad legal, social, and cultural forces.