The parties who "benefited":
- People who withdrew XCP that they bought before closing (this is the 7000)
- The hacker, who is up +80BTC
The parties who were unaffected
- People who did not have XCP on poloniex
Ideally, people who withdrew would deposit funds back into the exchange, the BTC would be redeposited, and all trades reversed, which would result in no one gaining or losing anything. However as this is not actually practical, the exchange is currently soliciting donations to try to cover the remainder.
That's the current fund situation right now.
Thanks for the good assessment of what happened at the exchange.
I'm encouraging those who benefited from the low XCP prices and withdrew the XCP to offer to return it to the exchange.
It might have looked like an fortuitous turn of events in your favor. However, you now know that it was caused by a bug in the protocol. It is the right thing to return what was not really yours to begin with.
If you decide to keep your windfall, know that you are benefiting from the misfortune of someone else in the community.
If more than 70% of the shortfall of XCP is returned to the exchange, I will personally donate 100% of all of the XCP that I would have lost (ie all of the buy orders which filled during the dump) to a bounty or donation fund for XCP.
Edit: I decided to lower the barrier from 80% to 70%