Craig Wright claims that he bought them from Mt Gox
No, he claimed to have bought them from a long defunct russian exchange. Of course, the supposed seller say it was nonsense and the "invoice" wright produced was obviously fake, including having mistaken some russian section heading of their website as their logo. In any case, Wright withdrew that lawsuit after we obliterated his evidence, was forced to pay our legal expenses, and the the UK courts went on to certify his lawsuit as totally without merit. He's just a scumbag scammer, one of many in a scumbag laden ecosystem.
MTGox was hacked many, many times, by multiple unrelated parties. These were funds pulled out in one of the hacks.
You want some real intrigue go look at who was laundering money for some of the mtgox hackers and how.