[This article applies the methodology of Bai and Ng (2002, 2004) for decomposing panel data into systematic and idiosyncratic components to both stock returns and turnover panels. This approach works well for both returns and turnover, despite the presence of severe heteroscedasticity and nonstationarity of individual stocks' turnover. We test the mutual fund separation model of Lo and Wang (2000). Trading due to systematic risk in returns can account for 66% of systematic turnover. Thus, portfolio rebalancing due to systematic risk is a very important motive for stock trading. Finally, several common turnover measures may understate the impact of stock trading.]

[We investigate the effects of shareholder governance mechanisms on bondholders and document two new findings. First, the impact of shareholder control (proxied by large institutional blockholders) on credit risk depends on takeover vulnerability. Shareholder control is associated with higher (lower) yields if the firm is exposed to (protected from) takeovers. In the presence of shareholder control, the difference in bond yields due to differences in takeover vulnerability can be as high as 66 basis points. Second, event risk covenants reduce the credit risk associated with strong shareholder governance. Therefore, without bond covenants, shareholder governance, and bondholder interests diverge.]

We investigate the effects of shareholder governance mechanisms on bondholders and document two new findings. First, the impact of shareholder control (proxied by large institutional blockholders) on credit risk depends on takeover vulnerability. Shareholder control is associated with higher (lower) yields if the firm is exposed to (protected from) takeovers. In the presence of shareholder control, the difference in bond yields due to differences in takeover vulnerability can be as high as 66 basis points. Second, event risk covenants reduce the credit risk associated with strong shareholder governance. Therefore, without bond covenants, shareholder governance, and bondholder interests diverge.

This article applies the methodology of Bai and Ng (2002, 2004) for decomposing panel data into systematic and idiosyncratic components to both stock returns and turnover panels. This approach works well for both returns and turnover, despite the presence of severe heteroscedasticity and nonstationarity of individual stocks' turnover. We test the mutual fund separation model of Lo and Wang (2000). Trading due to systematic risk in returns can account for 66% of systematic turnover. Thus, portfolio rebalancing due to systematic risk is a very important motive for stock trading. Finally, several common turnover measures may understate the impact of stock trading.