In the simplest terms, banks operate by taking in deposits and making loans. They set aside some of their money to cover losses from deadbeat borrowers. Healthy banks can increase those reserves with profits.
Sick banks have to call in loans to improve their financial position.
They can turn to fellow group companies for capital. But most of these companies are in trouble themselves. Marubeni, the trading company, was hit hard by the economic downturn in other Asian nations. Nissan Motor, Hitachi, Taisei and Oki Electric are all losing money as well. Yasuda Trust is in such dire shape that Fuji Bank had to lead a rescue operation in February.