A lack of so-called insider buying in which executives purchase stock from their own company, is a worrisome development, U.S. market analysts say.

Darren Roulstone, a professor of accounting at Ohio State University, called the trend "a little disturbing," USA Today reported Monday.

Executive purchases of their own company's stock shows confidence in the future. But, except for a few exceptions, executives aren't buying much these days in spite of fire sale stock prices, the newspaper said.

Stocks have fallen roughly 40 percent in the past 12 months. But, in the past three months, what might be called "insider selling" has been the norm, USA Today said.

"Clearly, it would be a favorable sign if insiders were actively buying their companies' stocks right now," Terrance Odean at the Haas School of Business at the University of California-Berkeley, told USA Today.

"The lack thereof is not good news." (c) UPI