Michael Saylor and large companies are buying millions, even billions, of $BTC , but why isn't Bitcoin going up? The reason is simple: their purchase comes from people who already hold $BTC . For example, if I own 100 $BTC and sell it, the price may drop if there isn't enough demand. When companies like Saylor buy, they usually buy from existing holders at higher prices. The buyer and seller agree on a fair rate, so there is no large sale or increase, and no major volatility. This is different from ETFs.