Insider Trading Law and Legal Definition

Insider trading is commonly referred to as the use of confidential information about a business gained through employment in a company or a stock brokerage, to buy and/or sell stocks and bonds based on the private knowledge that the value will go up or down. It is a crime under the Securities and Exchange Act. However, the term actually includes both legal and illegal conduct. The legal version is when corporate insiders—officers, directors, and employees—buy and sell stock in their own companies. When corporate insiders trade in their own securities, they must report their trades to the SEC.

Illegal insider trading refers generally to buying or selling a security, in breach of a fiduciary duty or other relationship of trust and confidence, while in possession of material, nonpublic information about the security. Insider trading violations may also include "tipping" such information, securities trading by the person "tipped," and securities trading by those who misappropriate such information.

The SEC adopted new Rules 10b5-1 and 10b5-2 to resolve two insider trading issues where the courts have disagreed. Rule 10b5-1 provides that a person trades on the basis of material nonpublic information if a trader is "aware" of the material nonpublic information when making the purchase or sale. The rule also sets forth several affirmative defenses or exceptions to liability. The rule permits persons to trade in certain specified circumstances where it is clear that the information they are aware of is not a factor in the decision to trade, such as pursuant to a pre-existing plan, contract, or instruction that was made in good faith.

Rule 10b5-2 clarifies how the misappropriation theory applies to certain non-business relationships. This rule provides that a person receiving confidential information under circumstances specified in the rule would owe a duty of trust or confidence and thus could be liable under the misappropriation theory.