Mattel Inc. is pursuing a fire sale of its Learning Co. software unit in a transaction that could reap less than a third of the $3.5 billion it paid to acquire the company last spring. The price for Learning Co. could range from less than $500 million to about $1 billion, depending on whether certain licensing rights are included. Such a low price could prompt even further scrutiny of the Mattel board, which approved the all-stock acquisition. Mattel's board and previous management already are the subject of numerous shareholder suits alleging mismanagement. Among prospective buyers expected to review the sale are Vivendi SA's Havas Interactive Inc., Internet incubator Knowledge Universe LLC, Microsoft Corp., Time Warner Inc., and Infogames Entertainment SA, people familiar with the proposed sale told The Wall Street Journal.