It ain't over till the fat lady sings. Investors are buying up Ashikaga Financial Group Inc. shares, never mind that regulators nationalized the group's core unit, Ashikaga Bank, after declaring it insolvent.

More than 426 million shares of Ashikaga FG traded hands on the day, with the price soaring 83 percent to a high of 22 yen, before closing at 18 yen.

Individual investors are leading the pursuit, looking for quick gains and potential tax perks, according to online trading companies and analysts.