Investing.com - Careful what you wish for Bill Gates.
After the Microsoft (NASDAQ:MSFT) founder told CNBC that he'd short bitcoin if there was an easy way to do it, crypto investor Tyler Winklevoss gave him instructions via Twitter.
"There is an easy way to short bitcoin," tweeted Winklevoss, who along with his twin brother, Cameron, founded the Gemini cryptocurrency exchange.
"You can short #XTB, the CBOE Bitcoin Futures contract, and put your money where your mouth is."
Futures contracts, of course, allow investors to bet on the future price of a security, commodity or other financial instrument.
Bitcoin futures have been available since December 2017, when both the CME and CBOE started trading.
The CBOE happens to use pricing information from Gemini to settle its daily contracts.
The Winklevoss brothers, who first invested in bitcoin in 2012, ranked 5th on Forbes' first crypto rich list.