•   Counterparty Risk —The Fund bears the risk that the counterparty to derivative transaction, such as a futures contract, defaults or otherwise fails to honor its obligations. If a counterparty defaults, the Fund will lose money and the value of an investment in the Fund may decrease. The Fund may engage in futures transactions with a limited number of counterparties, which may increase the Fund’s exposure to counterparty risk. The effect of the volatility of bitcoin pricing or other aspects of trading in bitcoin futures on futures clearinghouses for bitcoin futures is currently unknown, and may result in increased counterparty risk.
Short Term USD Emerging Markets Bond ETF; Crude Oil Strategy ETF; Inflation Expectations ETF; CDS Short North American HY Credit ETF and Short or Ultra Fixed Income ProShares Funds    2:30 p.m. (3:00 p.m., if transmitted by mail; except 4:00 p.m., if transmitted by mail on behalf of Short High Yield or Ultra High Yield) in order to receive that day’s closing NAV per Share

Bitcoin is pseudonymous rather than anonymous in that the cryptocurrency within a wallet is not tied to people, but rather to one or more specific keys (or "addresses").[53] Thereby, bitcoin owners are not identifiable, but all transactions are publicly available in the blockchain.[53] Still, cryptocurrency exchanges are often required by law to collect the personal information of their users.[53]
UPDATE: I do not recommend paying to enter a Cryptocurrency mastermind group – I’ve tried a few and found the ROI to be disappointing. I am now focussing on growing my portfolio passively utilising a cryptocurrency trading bot, the renowned Notorious Bot. Having a bot that trades for me, without emotion, using an advanced algorithm, allows me to grow my portfolio in the background without it cutting into my time or stressing me out. You can familiarise yourself with the basics of cryptocurrency trading bots here. 
XBT futures are cash-settled contracts based on the Gemini's auction price for bitcoin, denominated in U.S. dollars. Gemini Trust Company, LLC (Gemini) is a digital asset exchange and custodian founded in 2014 that allows customers to buy, sell, and store digital assets such as bitcoin, and is subject to fiduciary obligations, capital reserve requirements, and banking compliance standards of the New York State Department of Financial Services.
In general, a beneficial owner of Fund Shares who or which is a foreign shareholder is not subject to U.S. federal income tax on gains (and is not allowed a deduction for losses) realized on a sale of shares of the Fund unless (i) such gain effectively connected with the conduct of a trade or business carried on by such holder within the United States, (ii) in the case of an individual holder, the holder is present in the United States for a period or periods aggregating 183 days or more during the year of the sale or and certain other conditions are met, or (iii) the special rules relating to gain attributable to the sale or exchange of “U.S. real property interests” (“USRPIs”) apply to the foreign shareholder’s sale of shares of the Fund (as described below).
As a general matter, the Short ProShares Funds, the CDS Short North American HY Credit ETF and the Short Bitcoin Futures Strategy ETF respond differently in response to market conditions than the Matching ProShares Funds, the Ultra ProShares Funds, the Managed Futures Strategy ETF or the Crude Oil Strategy ETF. The terms “favorable market conditions” and “adverse market conditions,” as used in this SAI, are Fund-specific.

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: