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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Discover More

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

David Miller, the CFTC’s enforcement chief, has said insider trading on prediction markets is “a real problem.”

From The Wall Street Journal • Jun. 3, 2026

“I think it also underscores just how ripe for insider trading many of these markets are.”

From MarketWatch • May 28, 2026

On top of that, new prediction markets can pop up on just about anything, opening the door for insider trading on information that wasn’t previously considered material.

From MarketWatch • May 28, 2026

Polymarket and Kalshi—which allow users to bet on everything from geopolitical events to stock market moves—have made headlines in recent months after a batch of suspicious trades raised concerns of insider trading in Washington.

From The Wall Street Journal • May 26, 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