Insider trading occurs when corporate insiders (who may be officers, directors, and/or employees of a company) buy and sell stock of the company that employs them. When corporate insiders trade in their own securities, they must report those trades to the SEC, which makes this information available to the public. All publicly traded firms are required to monitor and control all trading by corporate insiders, and may even exclude certain employees from participating in the purchase of the company’s stock or related investments altogether.