While investors were dumping stocks in the last couple of weeks, CEOs were buying up shares of their own companies. Thousands of corporate insiders have taken the recent spate of panic selling as an opportunity to buy nearly $2 billion worth of their shares at the low prices, The Washington Post reported.

“They are really buying the shares of their companies in a big way,” author and University of Michigan professor Nejat Seyhun told the Post. Insiders selling shares normally tend to outpace buys by a 2-to-1 ratio, but this month its been nearly two buys for each sell, data Seyhun compiled for The Washington Post showed.

Seyhun said the reversal is a “very bullish” signal for the market, and could indicate a market bottom. He told the Post that jumps in stock purchases by corporate insiders helped spot market bottoms after the 1987 stock market crash and the financial crisis of 2008.

NYSE floor traders (Getty Images photo)

“It is a sign that at least corporate America is saying, ‘We can avert ‘a double-dip recession,’” Diane Swonk, chief economist at Mesirow Financial in Chicago, told the Post. Data show that more than 2,900 insiders at some of the biggest corporations have noticed buying opportunities.

Directors at Exxon Mobil, Berkshire Hathaway and General Motors have bought shares this month, which also saw insiders at Wells Fargo, Morgan Stanley, and JPMorgan Chase buying shares, the Post reported.

“This is the type of activity that has signaled market bottoms, and this is unusual in terms of the number of people buying, the number of companies seeing insider buying and the number of dollars flowing into stocks,” Ben Silverman, director of research at InsiderScore, told the Post.