Our learning-impaired whale friend continues to dump. Why he doesn't just sweep the bid stack down to zero, I do not know, because he obviously doesn't care how much money he leaves on the table.
I will call him Dipstick.
I will call him Dipstick.
Could it just be big miners that need to pay their electric bill? I'm still new to the game, but couldn't someone just buy large tranches of bitcoins directly from a huge petahash miner with no slippage at a price below the exchange rate, then carefully dump those coins on the exchanges? You could also figure out what the slippage would have been for the miner and give the miner a better deal than he would get if he sold the coins himself. Then withdraw the cash and wash, rinse, repeat, until mining difficulty and expenses catches up.