Front-running occurs when a financial expert talks up a company after having bought into it.
Imagine that a mutual fund manager is bullish on a company called Magazine Aromatics (ticker: WHIFF). If she buys some shares for her personal portfolio and then begins buying many shares for her fund, that will drive the price up, and she'll profit. Similarly, she might buy many shares of a company for her fund and then appear on television singing the company's praises. These are instances of front-running.
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