In general, the cleanest way to short something is using futures, if they exist. They do for Bitcoin: https://www.cmegroup.com/trading/bitcoin-futures.html http

In general, the cleanest way to short something is using futures, if they exist. They do for Bitcoin: https://www.cmegroup.com/trading/bitcoin-futures.html https://www.cmegroup.com/trading/bitcoin-futures.html .