By Michael Msika

(Bloomberg) -- US executives are selling shares at the second-fastest pace in more than 20 years, a classic red flag to some investors because it suggests people with the most corporate knowledge are wary about markets.

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Corporate insiders sold $77.6 billion of stock during the first half of 2026, a 20% increase from a year ago, according to EPFR Global Market Intelligence. The only time the selling spree was more intense was back in 2021, when markets were flush with pandemic-driven stimulus cash.

"Insider activity suggests executives are not especially eager to increase their exposure at current valuations," wrote analysts including Winston Chua at EPFR.

In contrast, stock buying by corporate insiders has been subdued. They purchased just $6.9 billion worth of shares in the first half. That's only modestly above the seven-year low of $6.7 billion recorded a year earlier.

"Insiders remain reluctant to increase personal equity exposure, even as equity markets have continued to advance," the EPFR team wrote.

The S&P 500 has rallied 10% this year and is on course for a fourth year of double-digit gains. However, more recently, traders are flashing nervousness that chipmakers have rallied too far, too fast and spending on artificial intelligence has become excessive. There's also concern that equity markets will become saturated with shares, as more big AI firms look to go public.

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