Assume there is 0 contracts open and 2 traders, and a new futures contract expiring in 7 days opens. You can "create" a contract by putting a limit sell order in the orderbook at a given price. If someone market buys that limit order, an open contract is created between you and the other trader. This is how you can go from a position of 0 to a negative exposure just by selling a contract.
the price of Bitcoin and Bitcoin Futures Contracts. In particular, it is possible that the price of the Bitcoin Futures Contracts subsequent to a “fork” may be linked to the price of bitcoin on only one of the resulting Bitcoin Networks, rather than the aggregate price of bitcoin on all resulting Bitcoin Networks. The CBOE Futures Exchange (“CFE”) and Chicago Mercantile Exchange (“CME”) have announced different protocols for addressing forks.
Trader A is a producer of pork bellies. In order to insure herself against a price drop in pork bellies in the future, she enters a futures contract with Trader B. Trader B uses these pork bellies to manufacture sliced breakfast bacon. Thus, he is not worried that prices might fall in the future – his worry is that prices will go up. Both traders agree that Trader A will sell a metric ton of pork bellies for 1,000 USD 3 months from now. This increases security for both of their businesses. Because a futures contract is a binding contract between two parties, neither party can drop out of the contract: Even if the price for pork bellies is 1,200 USD at the time of execution, trader A is still contractually obliged to sell for 1,000 USD.
!! WARNING !!! Note that on CryptoFacilities each contract is denominated by 1 BTC. So if you bought a fraction of BTC you can NOT perform a perfect hedge of the value. If you round the BTC you bought with start capital down, you will have slight overexposure LONG with the left-over BTC. If you round up and short an extra contract, you will have slight overexposure SHORT.