Posted on 2018/02/272018/02/26 by EditorPenguin: BitCoin Revolt Against Chinese Bitmain Miner?IO Impotency Share 0 Tweet 0 Share Email Print 0Shares Dare To Be Free! An open letter to the Bitcoin community to change the proof-of-work algorithm Based on conservative estimates of gross margin of 75 percent and operating margin of 65 percent, Bernstein analysts calculate that Beijing-based Bitmain made $3 billion to $4 billion in operating profits in 2017