No Goldi, they haven’t borrowed MY bitcoin! I know the Winklevoss twins have a large pot of them and wanted to found some financial ETF based on their holdings, but were denied at first. Things may have changed, I dunno.
But I DO know that Bitcoin trading is non-centralized so no single exchange can control the price with the tail (futures) wagging the dog (BTC). So the futures will FOLLOW the fundamental BTC price worldwide, not CONTROL it, like the rig does with gold prices. The only way to influence the fundamental price of BTC is with massive buy or sell of the actual BTC as delivered. It is impossible to ‘naked short’ BTC if you don’t have them in-hand. And they cannot be ‘borrowed’ like stocks (that you really don’t own, as they are held by the DTC).
I see the BTC futures being a massive problem for the sponsoring banks, due to the extreme volatility. They will get whipsawed and whacked, and have to cough up the dollars for their losses. The futures will be trading Dollar-equivalents… not actual BTC. Much like paper gold… you will not get delivery.