2014-02-25 22:02 GMT+01:00 fyl <fyl@a42.com>:

What I didn't understand until a few minutes ago is that MtGox wasn't
putting their transactions on the blockchain. Thus, the built-in
validation model that comes with bitcoin was being "worked around".

Could you be a bit more specific about transaction? A Bitcoin transaction /has/ to go into the blockchain. An MtGox internal transaction normally wouldn't. A trade definitely wouldn't, as it bridges fiat and crypto.