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

Sharp-eyed observers like Jeong are proving to be an unexpected ally of law enforcement as it tackles the emerging challenge of insider trading on prediction markets.

From The Wall Street Journal • May 28, 2026

Fischer said she believes that there is “way more” insider trading and misappropriation in these markets than law enforcement is able to catch.

From MarketWatch • May 28, 2026

They typically focus on Polymarket, whose offshore, crypto-based platform isn’t overseen by U.S. regulators and has drawn repeated allegations of insider trading and market manipulation.

From The Wall Street Journal • May 28, 2026

As a result, this also puts a strain on federal regulators like the Commodity Futures Trading Commission, which are charged with helping to stop insider trading.

From MarketWatch • May 28, 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