Intra-industry Connectedness, Large Shareholders Portfolio Diversification and Cost of Capital: The Moderating Role of Corporate Governance

Some major factors influencing investment include the investment risk and the consequent cost of capital imposed upon companies. Different studies demonstrated that intra-industry information transfer significantly influences the reporting environment and the quality of financial information. In case intra-industry information transfer within highly connected industries influences investor decisions and disclosure quality, it is expected to affect investor reactions to earnings, perceived risk, and the cost of capital. This study investigates the effect of intra-industry connectedness and diversification of major shareholders' portfolios on the corporate cost of capital, considering the moderating roles of ownership concentration and board gender diversity.

To achieve this goal, panel data from 144 companies listed on the Tehran Stock Exchange were collected from their annual financial reports from 2013 to 2020. A multivariate regression analysis was used. The diversification of major shareholders' portfolios was measured using the Rhoades (1993) method and the Herfindahl-Hirschman Index (HHI), while intra-industry connectedness was measured according to a model put forward by Chiu (2014). The diversification of major shareholders' portfolios was calculated by identifying the major shareholder's portfolio for each year, including listed and over-the-counter companies, and computing the Herfindahl-Hirschman Index (HHI) based on this data. Subsequently, the diversification index for each company-year was determined by computing the weighted average, considering the ownership percentage of major shareholders.

The results indicate a significant negative impact of both the diversification of major shareholders' portfolios and intra-industry connectedness on corporate cost of capital. Additionally, the degree of ownership concentration and gender diversity on the board shapes the magnitude of these associations. Ownership concentration strengthens the relationship between portfolio diversification and the cost of capital, while it weakens the relationship between intra-industry connectedness and the cost of capital. However, the presence of women on the board attenuates both relationships, implying that in companies with female board members, these relationships are less pronounced.

The confirmed negative relationship between the diversification of major shareholders' portfolios and the cost of capital aligns with the informational perspective. According to this perspective, the increased number and diversity of major shareholders' portfolios lead to higher costs for obtaining insider information, prompting the major shareholders to focus on public information and demand the investee company to provide more transparent and higher-quality information. This, in turn, reduces information asymmetry and the cost of capital. Furthermore, the results indicate a significant negative relationship between intra-industry connectedness and corporate cost of capital. Finally, the findings confirm the moderating effects of ownership concentration and board gender diversity on these relationships.