Mamma.com Loses Another Friend

At the time, many dismissed the SEC inquiry as a routine event. Last year dozens of so-called low-float stocks, companies with just a few million shares available for trading, were driven to new heights by daytraders and momentum players. Throughout the year, momentum traders flitted from one obscure stock to another, feasting on the volatility created by their low share count.

Indeed, at one point, even Dallas Mavericks owner Mark Cuban got in the low-float action, buying a 6.3% stake, or 400,000 shares of Mamma, back on March 4. But in July, Cuban cashed out, selling his entire position when the stock was trading around $11. Cuban's sale coincided with the end of Mamma's frenzied run. Ever since, the stock has been dropping back to the midsingle digits.

Shares of Mamma were trading around $5.74 when trading halted for the midday announcement about the accounting change. They've since reopened and were recently down $1.83, or 29%, to $4.45.

Company CFO Daniel Bertrand declined to comment on the auditor announcement or the SEC investigation.