Global bitcoin exchange Kraken said yesterday that significant progress has been made in the investigation into claims of creditors of bankrupt exchange MtGox, Reuters reported. MtGox Co Ltd, a Tokyo-based bitcoin exchange, was forced to file for bankruptcy in 2014 after hackers stole an estimated $650 million worth of customer bitcoins. Kraken was appointed in November of that year to assist Tokyo district court-appointed trustee Nobuaki Kobayashi in the bankruptcy investigation of missing bitcoins, receiving claims and distributing remaining assets to creditors of MtGox. Kraken said in a statement, citing the Tokyo-based trustee, that out of the 9,863 persons who filed bitcoin-only claims through the Japanese trustee or through Kraken's online service, 7,952 claimants have been approved.