TOKYO, March 21 (Reuters) - Mt. Gox said on Friday it found 200,000 "forgotten" bitcoins on March 7, a week after the Tokyo-based digital currency exchange filed for bankruptcy protection saying it had lost about $500 million worth of bitcoin, nearly all its holdings.
Mt. Gox made the announcement on its website. Online sleuths had noticed the same amount of bitcoin moving through the crypto-currency exchange after the bankruptcy filing.
The exchange said the bitcoins were found in an old-format online wallet which it had thought no longer held any bitcoins, but which it checked again after its bankruptcy filing.
"On March 7, 2014, MtGox Co., Ltd. confirmed that an old format wallet which was used prior to June 2011 held a balance of approximately 200,000 BTC," the statement said.
"For security reasons, the 200,000 BTC which were at first on the 7th moved to online wallets, were moved between the 14th and 15th to offline wallets. These bitcoin movements, including the change in the manner in which these coins were stored, had been reported to the court and the supervisor by counsels."
Reporting by Sophie Knight; Editing by Ian Geoghegan and Miral Fahmy