What happens if a malicious forks is introduced in the blockchain? I see two possible outcomes, with the latter much more likely than the former:<p>a) The blockchain protocol is the final arbiter of ownership, and those who purchased the stock in the other branch of the chain no longer own the stock. Caveat emptor.<p>b) Courts rule in favor of the people who actually bought the stocks and marks the attack branch as invalid. This is possible because the attack was witnessed by so many people.<p>It's unlikely that a fork would be resolved with (a), but if it does, there would be a lot of very pissed of investors and lawsuits. All it takes for such a fork to happen is someone with the motive to do it and the means to lean on a few mining pool operators.<p>It's more likely that we would see outcome (b), in which case, the courts are the final authority and then what the heck is the point of using an expensive, slow, poorly scalable, decentralized consensus system?<p>I totally see the value of a decentralized system despite the shortcomings, but if you're coming to do away with that aspect, what on earth is the point?