Since the introduction of futures, the price of bitcoin has gone up, suggesting that there were more As -- people who wanted to be long bitcoin synthetically -- than Cs -- people who wanted to be short synthetically -- though again it is still early. Crudely speaking, the arbitrage spread suggests that there are also more As than Bs: There are a lot of people who want to be long bitcoin without owning bitcoin, but not so many people who want to own bitcoin without being long bitcoin. (Which makes sense! If you bought a bitcoin and sold a futures contract when Cboe launched its futures last week, you could have locked in a risk-free arbitrage profit of something like $1,200. But if you had just bought a bitcoin, you'd be up about $3,000 by now.) The costs of trading actual bitcoins on bitcoin exchanges -- in terms of blockchain transaction costs, exchange withdrawal limits, etc. -- are significant enough that people who want bitcoin exposure are willing to pay about 2 percent to avoid them.
Whether a Fund realizes a gain or loss from futures activities depends generally upon movements in the underlying currency, commodity, security or index. The extent of a Fund’s loss from an unhedged short position in futures contracts or from writing options on futures contracts is potentially unlimited, and investors may lose the amount that they invest plus any profits recognized on their investment. The Funds may engage in related closing transactions with respect to options on futures contracts. The Funds will engage in transactions in futures contracts and related options that are traded on a U.S. exchange or board of trade or that have been approved for sale in the U.S. by the Commodity Futures Trading Commission (“CFTC”).
Each Fund may provide redemptions in portfolio securities or cash at the Advisor’s discretion. With respect to the Matching and Ultra ProShares Funds, the Index Receipt Agent makes available through the NSCC immediately prior to the opening of business on the Exchange on each day that the Exchange is open for business the portfolio securities that will be applicable (subject to possible amendment or correction) to redemption requests received in proper form (as defined below) on that day (“Fund Securities”). These securities, at times, may not be identical to Deposit Securities which are applicable to a purchase of Creation Units. The Fund may also, in its sole discretion, upon request of a shareholder, provide such redeeming shareholder a portfolio of securities which differs from the exact composition of the Fund Securities but does not differ in NAV.
  •   Inverse Correlation Risk — Since a portion of the Fund’s assets are invested in short positions in bitcoin futures contracts, the Fund will likely decline in value when the price of bitcoin futures contracts goes up (unless such losses are offset by gains in the value of the Fund’s positions in other investments), a result that is the opposite from the results of taking long positions in bitcoin futures contracts.
In this guide we don't want to deal with social loss risk, so use the FCA-regulated, London-based bitcoin derivatives exchange CryptoFacilities. They offer contracts with 2% margin requirement (50x leverage) as well as a 15% margin requirement (6.5x leverage). They are 100% bitcoin based, but they don't accept US customers. Sign up here to get started: