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 Trust, the Advisor and the Distributor each have adopted a consolidated code of ethics (the “COE”), under Rule 17j-1 of the 1940 Act, which is reasonably designed to ensure that all acts, practices and courses of business engaged in by personnel of the Trust, the Advisor and the Distributor reflect high standards of conduct and comply with the requirements of the federal securities laws. There can be no assurance that the COE will be effective in preventing deceptive, manipulative or fraudulent activities. The COE permits personnel subject to it to invest in securities, including securities that may be held or purchased by a Fund; however, such transactions are reported on a regular basis. The Advisor’s personnel that are Access Persons, as the term is defined in the COE, subject to the COE are also required to report transactions in registered open-end investment companies advised or sub-advised by the Advisor. The COE is on file with the SEC and is available to the public.
An initial coin offering (ICO) is a controversial means of raising funds for a new cryptocurrency venture. An ICO may be used by startups with the intention of avoiding regulation. However, securities regulators in many jurisdictions, including in the U.S., and Canada have indicated that if a coin or token is an "investment contract" (e.g., under the Howey test, i.e., an investment of money with a reasonable expectation of profit based significantly on the entrepreneurial or managerial efforts of others), it is a security and is subject to securities regulation. In an ICO campaign, a percentage of the cryptocurrency (usually in the form of "tokens") is sold to early backers of the project in exchange for legal tender or other cryptocurrencies, often bitcoin or ether.[62][63][64]
Each Fund may enter into swap agreements to invest in a market without owning or taking physical custody of securities. On a typical long swap, the counterparty will generally agree to pay the Fund the amount, if any, by which the notional amount of the swap agreement would have increased in value had it been invested in the particular underlying assets (e.g., an ETF, or securities comprising a benchmark index), plus the dividends or interest that would have been received on those assets. The Fund will agree to pay to the counterparty a floating rate of interest on the notional amount of the swap agreement plus the amount, if any, by which the notional amount would have decreased in value had it been invested in such assets plus, in certain instances, commissions or trading spreads on the notional amount. Therefore, the return to the Fund on such swap agreements should be the gain or loss on the notional amount plus dividends or interest on the assets less the interest paid by the Fund on the notional amount. As a trading technique, the Advisor may substitute physical securities with a swap agreement having investment characteristics substantially similar to the underlying securities. Some Funds may also enter into swap agreements that provide the opposite return of their benchmark or a security. Their operations are similar to that of the swaps disclosed above except that the counterparty pays interest to each Fund on the notional amount outstanding and that dividends or interest on the underlying instruments reduce the value of the swap, plus, in certain instances, each Fund will agree to pay to the counterparty commissions or trading spreads on the notional amount. These amounts are often netted with any unrealized gain or loss to determine the value of the swap.
Like any futures contract, trading in XBT futures is not suitable for all investors and involves the risk of loss. The risk of loss in XBT futures can be substantial. Market participants should, therefore, carefully consider whether such trading is suitable in light of their own circumstances and financial resources. For additional information regarding futures trading risks, see the Risk Disclosure Statement set forth in CFTC Regulation 1.55(b).

Almost every crypto-list today starts off with the king – Bitcoin! Satoshi Nakamoto created Bitcoin a long time ago, and it was the first cryptocurrency to step blinking into the bright light of the world! Bitcoin has surpassed all expecatations and continues to grow in value and popularity – despite recent setbacks and a lot of FUD from trolls and haters (read: traditional banks) online.  Will Bitcoin continue to increase in value in 2018? Recent trends say: Yes! In my opinion, any cryptocurrency portfolio should hold some Bitcoin.
Note that the market value of the contract fluctuates before settlement. You are not forced to hold the contract to expiration. As the spot market moves, the traded futures contract price also moves. There is a live orderbook of traders placing buy and sell orders and you are able to realize your profit or loss prior to expiration, just as if you were buying and selling a stock.
Bob's transaction confirms first so he goes on BFE and looks at the contract selections. He wants to trade on the January 9 expiration contract. The orderbook is empty and Bob wants to go long (profit off an increase in bitcoin). Since there are no offers available, he places a limit order in the orderbook for a bid at 400 of 1 contract, using his 0.2btc as collateral for the position.
This Statement of Additional Information (“SAI”) is not a prospectus. It should be read in conjunction with the Prospectus of ProShares Trust (the “Trust”), dated October 1, 2017, the Prospectus dated November 16, 2017 for ProShares Decline of the Retail Store ETF, the Prospectus dated November 16, 2017 for ProShares Long Online/Short Stores ETF, the Prospectus dated             , 2018 for ProShares Bitcoin Futures Strategy ETF, the Prospectus dated             , 2018 for ProShares Short Bitcoin Futures Strategy ETF, the Prospectus dated             , 2018 for ProShares Blockchain/Bitcoin Strategy ETF, and the Prospectus dated             , 2018 for ProShares Bitcoin Futures/Equity Strategy ETF each as may be amended or supplemented, each of which incorporates this SAI by reference. A copy of the Prospectuses and a copy of the Annual Report to shareholders for the Funds that have completed a fiscal year are available, without charge, upon request to the address above, by telephone at the number above, or on the Trust’s website at The Financial Statements and Notes contained in the Annual Report to Shareholders for the fiscal year ended May 31, 2017 are incorporated by reference into and are deemed part of this SAI. The principal U.S. national stock exchange on which all Funds (except those noted below) identified in this SAI are listed is NYSE Arca. The S&P MidCap 400 Dividend Aristocrats ETF, the Russell 2000 Dividend Growers ETF, the ProShares MSCI Emerging Markets Dividend Growers ETF, the ProShares S&P 500 Dividend Aristocrats ETF, the ProShares MSCI EAFE Dividend Growers ETF, the MSCI Europe Dividend Growers ETF, the Morningstar Alternatives Solution ETF, the Global Listed Private Equity ETF, the Large Cap Core Plus, the High Yield—Interest Rate Hedged, the Investment Grade—Interest Rate Hedged, the Short Term USD Emerging Markets Bond ETF, the ProShares Managed Futures Strategy ETF, the Merger ETF, K-1 Free Crude Oil Strategy ETF and the CDS Short North American HY Credit ETF are listed on the Bats BZX Exchange, Inc. The UltraPro Short QQQ®, the UltraShort Nasdaq Biotechnology, the UltraPro Short Nasdaq Biotechnology, the UltraPro QQQ®, the Ultra Nasdaq Biotechnology the UltraPro Nasdaq Biotechnology and the Equities for Rising Rates ETF are listed on The NASDAQ Stock Market.
In traditional financial markets, derivatives are used as speculation objects as well as insurance against losses. The latter is known as hedging. One popular variety of derivatives used for hedging are called futures. A future is a contract between two parties in which one party agrees to pay the other a predetermined amount of money for an underlying asset at a specific point in time.