First of all, according to SEC regulation, AP (can be regarded as a market maker) must buy #BTC spot, but the way to buy spot is not very fixed, that is to say, when a user buys it at a brokerage After spot ETF, AP only needs to have the new corresponding number of BTC. For example: The user bought a spot ETF worth one #Bitcoin at $IBIT. At this time, the AP needs to hedge the price first (more on this later), and then "mobilize" a new BTC, and the source of this BTC can be :Buy from exchange...