In an intriguing shift within the spotBitcoin (CRYPTO: BTC) ETF market, the group of ETFs experienced a net outflow of $41.1 million on day three, signaling a cautious stance from investors in certain funds while others gained traction. Grayscale Bitcoin Trust (OTC: GBTC) bore the brunt of this movement, with a staggering net outflow of $590 million, according to BitMEX Research. This figure stood out not only within the day’s trading but also represented a significant portion of the trust’s total assets. GBTC, a flagship product of Grayscale, has long been a gauge of institutional and seasone…