" Terms of Service
By using the pool you accept all possible risks related to experimental software usage.
Pool owner can't compensate any irreversible losses, but will do his best to prevent worst case."
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While I am not a lawyer, I don't think that warning people you might commit fraud is a sufficient legal defense against criminal prosecution (it might be sufficient to protect against civil suits, though). Also, there is a difference between failing to pay someone for mining because of a software glitch or the like, and paying yourself with their mining...