Here is a
guide to bankruptcy in Japan, from Japan's largest law firm, Nishimura & Asahi:
IV. Liquidation under Bankruptcy Code
A. Commencement of Proceedings
An application can be made if (i) the debtor is unable to pay its debts generally or (ii) the liability of the debtor exceeds the value of the assets of debtor. Suspension of payment by the debtor shall be considered that the debtor is unable to pay its debts generally. An application for bankruptcy proceedings can be made not only by the debtor but also by creditors against the debtor....
D. Administration of Bankruptcy
1. Appointment of Administrator
The administrator is generally a practicing attorney. The administrator takes immediate possession of the debtor's assets (with the exception of assets which are exempt from the estate), administering and managing the bankruptcy estate until the final distribution of assets. Upon receiving permission from the court or the supervisory committee as described below, the administrator may convert all such assets into cash and deposit such in an appropriate bank.Bankruptcies start fast - a week or two from filing to bankruptcy.
This will require a lawyer in Japan. It's what normally happens to companies in Japan who don't pay their bills.
Depositors with Mt. Gox may be able to argue that they have preferred status as secured creditors, because the Mt. Gox terms of service claim that depositor funds are kept in bank accounts separate from the company's own funds. So they should be paid before landlords, employees, etc.