Easy to understand , in japan a Bitcoin has no value , it's not an asset that count in your accounting. So why 63 Millions ? Because Mtgox has lost this amount of your fiat money ...
They have a negative balance with:
-744 408 customers' bitcoins
- around 100 000 mtgox' bitcoins
- 63M fiat customers
They have in assets :
22,43 M$ of customers in bank account
5M$ Held by coinlab . Why ?
5.5M$ held by DHS . (Seized by usa ?)
So all peoples with bitcoins , they are really lost.
Peoples with fiat have a little chance to recover maybe around 30% of their fiats.