A corporate action is an action taken by a public company that has a direct effect on the holdings of its shareholders. The most common example of a corporate action is a dividend, a payment to the shareholder of company profits. Other examples include cash from the sale of rights, stock splits, and the release of warrants or options on the security.

Raising additional debt through the release of a bond is not typically considered a corporate action. Although such debt changes the finances of the company, it does not directly effect the valuation of the stock.