Mitsubishi UFJ Financial Group likely lost as much as $470 million on subprime investments last year, more than 10 times more than its previous estimate, sources said on Wednesday.
Japan's largest bank likely suffered subprime losses of 50 billion yen for the 12 months to December, up from the 4 billion yen it previously reported for the six months to September, according to executives with direct knowledge of the matter.
The executives spoke on the condition of anonymity because the information has yet to be announced.
Mitsubishi UFJ and other large Japanese banks have so far avoided the heavy losses that hit overseas rivals such as Merrill Lynch, due to smaller investments in subprime-related products.
In November MUFG posted a nearly 50 percent drop for the April-September first half, hit by subprime losses. At the time it also said subprime-related writedowns totaled 23 billion yen.