I'm confused by double-spend linked below, in which both transactions ended up in blocks mined by different miners. Specifically, I'm wondering if there's any way to tell what exactly happened based on the available information.
Based on my limited understanding of bitcoin, I'm assuming this could have happened in one of the following three ways. If I'm wrong, or if I'm missing other possibilities, could someone please let me know?
1) The double-spender broadcast the first transaction to the network, and then mined his own block containing a transaction using the same output. He ultimately wasn't able to "outrun" the honest blockchain, but he managed to mine his block quickly enough that some nodes in the network received it before receiving the longer blockchain. So both blocks were briefly accepted by parts of the network, and one was eventually "orphaned" (so its transactions are unconfirmed).
2) Same situation, but the double-spender's blockchain prevailed and the block containing the first transaction broadcast to the network was orphaned.
3) The double-spender didn't mine anything, he just tried a normal double-spend against someone who doesn't require confirmations. Both transactions happened to be included in blocks that were mined simultaneously by different miners in the network, and one was orphaned.