BRIEFLY / TECHNOLOGY

FileNet Corp. shares rebounded 45% on Friday after a 57% plunge the previous day as investors bet the software maker’s prospects will improve even though it said it will post an unexpected loss for the third quarter. Shares of the Costa Mesa maker of information-management systems jumped $2.06 to $6.63 in trading of 5.5 million shares, more than eight times the three-month daily average. The stock had tumbled Thursday after the company said it will report the three-month loss because of worldwide economic concerns and trouble integrating a new sales force. Sellers may have overreacted to the news, analysts said, sparking demand for the stock from investors who are more optimistic about the company’s prospects. “The stock was driven lower on valid concerns, but this isn’t a fly-by-night company,” said Dave Hilal, an analyst at Friedman, Billings, Ramsey, who rates FileNet “accumulate.” “People took advantage of a good buying opportunity.” The company said it will have a loss of 18 cents a share, compared with the 14-cent-a-share profit that analysts had expected.