The Chicago Board Options Exchange (CBOE) launches the first Bitcoin futures contracts on a regulated U.S. exchange, with CME Group following a week later on December 18. The CBOE website crashed within minutes due to overwhelming demand.
Bitcoin futures gave institutional investors their first regulated way to gain exposure to Bitcoin's price movements. The launch was a watershed moment for Bitcoin's acceptance by traditional finance, though some argue the introduction of derivatives also enabled new forms of price suppression.
Wikipedia: Bitcoin Futures