Insider Trading Law

Insider trading law prohibits buying or selling securities while in possession of material nonpublic information. The prohibition is enforced through the Securities Exchange Act of 1934, primarily Rule 10b-5. Officers, directors, and large shareholders must disclose trades to the SEC. Violations can result in civil penalties, disgorgement, and criminal imprisonment. Insider trading prosecutions are among the SEC’s highest-profile cases.

What is insider trading?

Insider trading is buying or selling a security while possessing material nonpublic information. Material information is information a reasonable investor would consider important. Nonpublic means the information has not been widely disclosed. Trading on such information is illegal because it is unfair — one trader knows something the market does not.

Insiders include officers, directors, employees with access to confidential information, and anyone who receives confidential information from an insider (a “tippee”). A person commits insider trading by trading on the information or by tipping others who trade.

Section 16 reporting: Form 4

Section 16 of the Securities Exchange Act of 1934 requires officers, directors, and shareholders holding 5% or more to file Form 4 within two business days of trading their company’s securities. Form 4 is a public filing; anyone can see what insiders are buying and selling.

This transparency serves two purposes. First, it deters insider trading — insiders know their trades will be public and scrutinized. Second, it provides information to other investors — if an insider is buying heavily, that may be a bullish signal; if selling, it may be bearish.

The “misappropriation” theory

Insider trading law covers two cases. First, a traditional insider (officer, director) trades on material information the company gave them. Second, a person misappropriates information — a lawyer, accountant, journalist, or M&A banker learns confidential information and trades on it. Misappropriation is trading while owing a duty of confidentiality to the information source.

The misappropriation theory has been contentious. Some argue that a lawyer who trades on confidential client information should be liable (the information belongs to the client). Others argue that insider trading law should focus only on insiders of the company whose stock is traded, not external parties.

The Supreme Court upheld the misappropriation theory in United States v. O’Brien (1988), confirming its validity.

The scienter requirement: intent

Insider trading requires scienter — intent or recklessness. A person cannot be liable for trading on information they did not know was nonpublic, or for carelessly trading without realizing they had inside information. However, recklessness is a low bar — highly unreasonable conduct counts.

Tipping and the Dirks rule

Tipping — providing nonpublic information to another person to trade on — is also illegal. A tipper violates Rule 10b-5; the tippee also violates it by trading on tipped information. In Dirks v. SEC, the Supreme Court held that a tippee is liable only if the tipper has breached a duty by tipping.

The Dirks rule focuses on whether the tipper received a personal benefit from tipping (money, friendship favor, insider status). If the tipper tipped for personal benefit, both tipper and tippee are liable.

Criminal prosecution and sentencing

The DOJ prosecutes insider trading criminally. Notable cases include Martha Stewart (convicted of insider trading-related charges, though the prosecution was for conspiracy, not the trade itself), Raj Rajaratnam (founder of Galleon hedge fund, imprisoned 11 years for insider trading), and more recently, Elizabeth Holmes (Theranos founder, convicted of wire fraud and conspiracy related to misrepresentation, not purely insider trading).

Criminal sentences for insider trading can be substantial — 5–20 years imprisonment. Disgorgement (forfeiture of illegal gains) is typical. Civil penalties add multiples of the gains or losses.

Controversies and the “rule of law” debate

Insider trading law has been criticized for imprecision. When does a person “possess” nonpublic information? Can a CEO, who knows many future events, ever trade? Is trading on research about a company’s sector different from trading on a tip about the company?

Some economists argue insider trading should be permitted or at least decriminalized — they view it as a victimless activity that provides price-discovery benefits. Others argue it is fundamentally unfair and must be prosecuted vigorously to maintain market confidence.

See also