Share repurchase conveys information to investors and influences stock price in capital market. Normally when a company announces share buyback, the company's stock price will rise immediately. Thus, some insiders may take advantage of this pattern and create a fake repurchase event. When the...

We analyze a dynamic model of informed trading where a shareholder accumulates shares in an anonymous market and then expends costly effort to change the firm value. We find that equilibrium prices are affected by the position accumulated by the shareholder, because the level of effort...