insider trading

American  

noun

1. the illegal buying and selling of securities by persons acting on privileged information.

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insider trading Cultural  

1. The unlawful practice of using information that comes from a source “inside” the business but is not available to the general public to trade on the stock market. This activity is prohibited by law and is policed by the Securities and Exchange Commission.

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In the mid-1980s, several revelations of insider trading rocked Wall Street.

Other Word Forms

Derived Forms

• insider trader
  noun

Etymology

Origin of insider trading

First recorded in 1965–70

Example Sentences

Kalshi said it would use a risk scoring method to identify markets that appear more at risk of manipulation or insider trading, such as those on national security matters.

From BBC • Jun. 9, 2026

Kalshi is planning to require that participants in some prediction markets disclose the identity of their employers, after an advisory committee recommended tighter security measures to combat potential insider trading and market manipulation.

From The Wall Street Journal • Jun. 9, 2026

People looking to place certain bets on prediction market operator Kalshi will soon have to reveal where they work in an attempt to stop insider trading, the firm has said.

From BBC • Jun. 9, 2026

The changes come following two recent high-profile insider trading cases involving Polymarket users and a congressional probe of how both Kalshi and Polymarket manage insider trading risk.

From The Wall Street Journal • Jun. 9, 2026

Paolo’s father was a real estate mogul who had been indicted for insider trading some months ago.

From "Genuine Fraud" by E. Lockhart