According to BlockBeats, as of April 10, US ETF investors hold 838,730 Bitcoins, which accounts for 4.3% of the total circulating supply of Bitcoin. If we exclude the number of Bitcoins that have not moved in the past three years (9,650,000), the percentage held by US ETF investors rises to 8.4%. This data was compiled by HODL15Capital.

The significant holding of Bitcoin by US ETF investors indicates their confidence in the digital currency. Despite the volatile nature of cryptocurrencies, these investors continue to hold a substantial amount of Bitcoin. This could be seen as a positive sign for the future of Bitcoin, as it shows that even institutional investors are willing to hold onto the cryptocurrency despite its fluctuations.

However, it's important to note that the percentage of Bitcoin held by US ETF investors could change rapidly due to the dynamic nature of the cryptocurrency market. The number of Bitcoins that have not moved in the past three years is also a significant factor to consider, as it could potentially impact the percentage of Bitcoin held by US ETF investors.