Decentralized cryptocurrency is produced by the entire cryptocurrency system collectively, at a rate which is defined when the system is created and which is publicly known. In centralized banking and economic systems such as the Federal Reserve System, corporate boards or governments control the supply of currency by printing units of fiat money or demanding additions to digital banking ledgers. In case of decentralized cryptocurrency, companies or governments cannot produce new units, and have not so far provided backing for other firms, banks or corporate entities which hold asset value measured in it. The underlying technical system upon which decentralized cryptocurrencies are based was created by the group or individual known as Satoshi Nakamoto.[28]

Basically, if you trade margin spot on a site like Kraken or Bitfinex, you will pay financing fees while you hold the position open. The same goes for CFD sites like WhaleClub or 1Broker. With bitcoin futures, you are able to trade margin without expending interest, because counterparties to the contract pay a fee to open and close the contract, and the exchange just manages the risk, so no money is really being lent!

  •   Lack of regulation. Digital commodities and their associated platforms are largely unregulated, and the regulatory environment is rapidly evolving. As a result, blockchain companies may be exposed to adverse regulatory action, fraudulent activity or even failure. Blockchain companies may face political or legal challenges from competitors, industry groups or local and national governments. New regulations may have a negative impact on blockchain technology and blockchain technology companies.
The Funds may invest in bitcoin-based futures contracts, swap agreements, and options contracts, which are types of derivative contracts. A derivative refers to any financial instrument whose value is derived, at least in part, from the price of an underlying security, commodity, asset, rate, or index. The use of derivatives presents risks different from, and possibly greater than, the risks associated with investing directly in traditional securities. Changes in the value of a derivative may not correlate perfectly with the underlying security, asset, rate or index. Gains or losses in a derivative may be magnified and may be much greater than the derivative’s original cost. Because bitcoin-based derivatives were only recently introduced, the degree to which bitcoin-based derivatives are likely to provide exposure to movements in the price of bitcoin is extremely uncertain. If market participants executing trades in bitcoin-based derivatives face constraints, including capital constraints, security risks, or high execution costs with respect to direct investments in bitcoin, the price at which bitcoin-based derivatives trade may fail to capture price movements in the underlying price of bitcoin. Moreover, it is not clear how changes to the Bitcoin Network and determinations by any relevant derivatives exchange with respect to such changes to the Bitcoin Network will affect the value of any positions in bitcoin-based derivatives. [[In December 2015, the SEC proposed a new rule to regulate the use of derivatives by registered investment companies, such as the Fund. Whether and when this proposed rule will be adopted and its potential effects on the Fund are unclear as of the date of this Prospectus.]]
Any distribution of income that is attributable to (i) income received by a Fund in lieu of dividends with respect to securities on loan pursuant to a securities lending transaction or (ii) dividend income received by a Fund on securities it temporarily purchased from a counterparty pursuant to a repurchase agreement that is treated for U.S. federal income tax purposes as a loan by the Fund, will not constitute qualified dividend income to individual shareholders and will not be eligible for the dividends-received deduction for corporate shareholders.

Making money arbitraging bitcoin futures can be extremely simple. Futures contracts typically trade at a premium, and all you have to do, starting with USD, is buy bitcoin at Spot price and sell futures of the same amount at premium price. Then just wait until expiration to make your arb profit in bitcoin (which you can then put in USD). Whether it's a weekly, monthly, quarterly, or any futures contract, as long as it's in a premium, you lock in the sale price and earn the arbitrage profit.