Long-Term versus Short-Term Institutional Ownership and Stock Liquidity: Evidence from the Tehran Stock Exchange

This study examines the relationship between institutional investors' investment horizon and stock liquidity in the Tehran Stock Exchange (TSE). Although previous studies have extensively investigated institutional ownership and liquidity, limited attention has been devoted to distinguishing between long-term and short-term institutional investors, particularly in emerging markets. This study addresses this gap by analyzing how institutional investment horizon influences stock liquidity in the Iranian capital market. Using a balanced panel dataset consisting of firms listed on the Tehran Stock Exchange during the period Y. ۱۰_Y. ۱۹, the study employs fixed-effects panel regression models to examine the impact of institutional ownership structure on stock liquidity. Stock liquidity is measured using the Amihud (YY) illiquidity ratio, while institutional ownership is classified into long-term and short-term ownership categories. Several control variables, including firm size, leverage, return on assets, turnover ratio, and stock return volatility, are incorporated into the regression models to improve estimation reliability. The empirical findings reveal that long-term institutional ownership negatively affects stock liquidity because long-term investors adopt buy-and-hold strategies that reduce trading activity and market turnover. In contrast, short-term institutional ownership positively influences stock liquidity through active trading behavior and portfolio rebalancing. The results further indicate that trading turnover strengthens the relationship between institutional ownership and liquidity. These findings support information asymmetry theory and market microstructure arguments regarding the role of informed trading in liquidity determination. This study contributes to the literature by emphasizing the heterogeneity of institutional investors and demonstrating the importance of investment horizon in explaining liquidity dynamics in emerging markets. The findings provide practical implications for regulators, policymakers, investors, and corporate managers seeking to improve market liquidity, transparency, and financial market efficiency.

کلیدواژه ها:

Institutional Investors ، Investment Horizon ، Stock Liquidity ، Emerging Markets ، Market Microstructure ، Information Asymmetry