And more importantly, at what point does the ETF actually buy new coins? If the Winklvii have 100K BTC, do they sell all those first before the ETF buys any more? (So it might actually have a negative effect on the price as more supply is available and some people may chose to buy the ETF instead of buying coins on an exchange?)
Is the ETF a close-ended fund? In that case, it will be open for subscriptions for a certain period of time. As and when people subscribe, the ETF will buy bitcoins to match the subscriptions.
no, it is like GLD, to my knowledge. Winkies just provide the initial liquidity.
What I don't remember is whether there is a yearly maintenance fee.
If yes, hopefully, it is small; GLD fee is 0.4% yearly.
That's the downside of ETFs plus tx fee each way, which is $5-10 in almost all brokerages.
GBTC has an annual fee of 2%, which is way too much.