Crypto shares fall, tracking weakness in bitcoin

** Shares of cryptocurrency and blockchain-related companies down in premarket trading, as bitcoin falls** Bitcoin , the world's biggest cryptocurrency, falls 1.2%, while Ether slides 2.2%** Crypto exchange Coinbase Global falls 5.7%, U.S.-listed shares of blockchain farm operator Bitfarms down 3.2%** Crypto miners Riot Platforms , Hut 8 Mining and Marathon Digital down between 4% and 5%** Bitcoin miner CleanSpark slides 4.1%, while software firm and major crypto bull MicroStrategy falls 5.1%