What it is:
An activist investor invests in a company for the purpose of changing or influencing the company's decisions.
How it works (Example):
Carl Icahn, known as a corporate "raider" in the 1980s, is one of the most famous activist investors. He buys a substantial portion of a company's and then pressures management to take actions that are sometimes uncomfortable but ultimately in the best interest of the shareholders.
Accordingly, when news hits that Carl Icahn has invested in a company, the undervalued, but because investors know Icahn would a of pressure on the company's management to run the company more efficiently and more in the interests of the shareholders (rather than the management).'s value typically rises not only because the sees that a sophisticated investor believes the company is
Activist investors may have a variety of agendas, however -- changing the company's environmental actions, changing the company's product lines, changing the company's compensation plans, etc.
One way to tell whether a company has been or is being targeted by activist investors is to review its SEC Form 13-D filings, which disclose when an entity has acquired 5% or more of a company's shares.
Why it Matters:
Corporations that operate for a money doing so, the other shareholders benefit too (this effect is nicknamed the ).