Final answer:
Overinvestment by managers includes empire-building, entrenching investments, and investing beyond the point of positive NPV, all of which can negatively impact shareholder value.
Step-by-step explanation:
The actions by managers considered as examples of overinvestment include empire building, entrenching investments, and investing beyond the point where the Net Present Value (NPV) falls to zero. Overinvestment can occur when managers engage in projects that might increase the size and power of the company but do not necessarily add to its value or profitability, which is referred to as empire building.
On the other hand, entrenching investments are those that protect the position of managers, even if they are not in the best interest of the shareholders. Additionally, managers might invest in projects even after the point where they are no longer generating positive NPV, which means the cost of the investment exceeds the present value of its expected future cash flows, thus destroying shareholder value.