KEY POINTS:
America's third-largest investment bank has taken a hammering.
Merrill Lynch waited until after the sharemarket closed today to announce it expects to take a US$5.7 ($7.75) billion pretax write-down in the third quarter, due to losses on the sale of mortgage assets.
Merrill has already taken billions of dollars in write-downs in past quarters and said it sold key holdings - including a 20 per cent stake in Bloomberg - when it announced second-quarter earnings.
