Spot Bitcoin ETFs in the US now hold nearly $30 billion, marking the most successful launch in ETF history, with +30K BTC netflows last week. Fidelity's Bitcoin ETF led the inflows on March 15th with approximately $155 million, bringing its total to $6.87 billion. Overall, Bitcoin spot ETFs saw a $198 million inflow, while Grayscale's GBTC faced an outflow of $139 million. Nine new Bitcoin ETFs have accumulated 450,000 BTC worth over $30 billion. BlackRock's iShares Bitcoin Trust now holds more Bitcoin than Microstrategy, managing over 228K BTC, with a weekly inflow of 34.6K BTC. Two spot Bitcoin ETFs, IBIT and FBTC, are now in the top 6 of all ETF inflows this year, out of over 3,400 ETFs. The sector has also seen a record $2.9 billion weekly inflow into crypto-based investment products, with total inflows since the beginning of the year rising to $13.2 billion. However, Grayscale experienced a record outflow from its spot Bitcoin ETF with $643 million worth being sold, contributing to a net outflow of $154m from Bitcoin ETFs, with the total Bitcoin held in ETFs now at 833.8K BTC. A record low inflow for Fidelity's FBTC was only +$5.9M on the same day.