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There is a documented case from 2010 when a block with 92 billion bitcoins was discovered. The bug was found and software was patched within 5 hours and everyone had to "hit the load button" to an earlier blockchain. It was speculated to be malicious. My question is: did anyone try to make transactions with the hacked bitcoins? If not, is it possible the bug was exploited accidentally?
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Someone might have a copy if they have a long-running node - they would have had to have upgraded while the hard fork took place to be synchronized today
The transaction was executed by someone who knew of, and wanted to demonstrate the issue. The overflow meant the summed output value was less than the total input amount, despite actually minting billions of bitcoin out of thin air.
It's unlikely the problem would have happened accidentally, the amounts would have been crafted to trigger the bug: two outputs with amounts exceeding the 21 million limit are required to trigger it, so with just one, it would have been rejected.
This question, while interesting, is quite hard to answer. It's answer is historical and can probably only be answered by someone who was involved with this transaction. I will add, though, that given the level of precision in the output, and the fact that the outputs had to add up and overflow to less than the sum of the inputs, it seems unlikely that it was an accident. – morsecoder – 2016-07-06T16:19:17.737
Maybe someone has a copy of the bad blockchain and they could check if there were any transactions from the bad block? – Atte Juvonen – 2016-07-06T18:58:28.897
May be, double spent is possible in few cases, but not certainly from one of 92 billion btc. Those are part of ignored chain, and any transactions using those bitcoin will also become invalid. – vi.su. – 2016-07-07T09:47:11.860