We have both instant payout (without any 120/100 confirmations) and pays for invalid blocks (orphans).
We have a reserved amount of bitcoins ready for handling both orphan blocks and having that 50 btc "buffer". This comes from a combination of generous donations and my own wallet

This way, you'll always be 100% sure that you'll get paid for your work, even if our network/peers are to slow to distribute your work - and the block becomes orphan.
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Regards, Jim
Bit LC INC.
That's some nice little (and completely irrelevant) advertising you are doing there.