Merrill Lynch & Company, the world's largest brokerage firm, reported its first loss in six years as a publicly traded company on Monday after writing down $7.9 billion for bad bets on risky mortgages and related securities. Merrill Lynch's third-quarter net loss was $2.3 billion, or $2.85 a share, from continuing operations in the third quarter, compared with a profit of $3 billion, or $3.14 a share, a year earlier. More write-downs could follow if the company decides to further cut the value on its remaining $20.9 billion exposure to collateralized loan obligations and so-called subprime mortgages. Merrill Lynch shares fell about 3 percent to $65.05, near a two-year low, in morning trading on the New York Stock Exchange. The company was the only big Wall Street firm to post a third-quarter loss and its write-downs were larger than the combined $3.6 billion in write-downs and charges recorded by three of its rivals The write-downs figures were more than the $5.5 billion Merrill forecast earlier this month, but it re-examined its positions on collateralized debt obligations subsequently and used more conservative assumptions for valuing those assets. Merrill said the net write-down figure does not include a $967 million write-down, before fees, on commitments that include loans for takeovers. Merrill shares are down 28 percent this year and fell before the third-quarter results were released as investors anticipated the bigger-than-expected write-downs, Reuters reported.