Sections 1471-1474 of the Code and the U.S. Treasury and IRS guidance issued thereunder (collectively, “FATCA”) generally require a Fund to obtain information sufficient to identify the status of each of its shareholders under FATCA or under an applicable intergovernmental agreement (an “IGA”). If a shareholder fails to provide this information or otherwise fails to comply with FATCA or an IGA, a Fund or its agent may be required to withhold under FATCA at a rate of 30% with respect to that shareholder on ordinary dividends it pays to such shareholder and 30% of the gross proceeds of share redemptions or exchanges and certain Capital Gain Dividends it pays to such shareholder after December 31, 2018. If a payment by a Fund is subject to FATCA withholding, the Fund or its agent is required to withhold even if such payment would otherwise be exempt from withholding under the rules applicable to foreign shareholders described above (e.g., Capital Gain Dividends, short-term capital gain dividends, and interest-related dividends).
In cryptocurrency networks, mining is a validation of transactions. For this effort, successful miners obtain new cryptocurrency as a reward. The reward decreases transaction fees by creating a complementary incentive to contribute to the processing power of the network. The rate of generating hashes, which validate any transaction, has been increased by the use of specialized machines such as FPGAs and ASICs running complex hashing algorithms like SHA-256 and Scrypt.[38] This arms race for cheaper-yet-efficient machines has been on since the day the first cryptocurrency, bitcoin, was introduced in 2009.[38] With more people venturing into the world of virtual currency, generating hashes for this validation has become far more complex over the years, with miners having to invest large sums of money on employing multiple high performance ASICs. Thus the value of the currency obtained for finding a hash often does not justify the amount of money spent on setting up the machines, the cooling facilities to overcome the enormous amount of heat they produce, and the electricity required to run them.[38][39]
Yes but ... in cryptocurrencies? If you had borrowed 100 bitcoins to finance your working capital needs a year ago, you'd have financed about $79,000 worth of working capital. If you had to pay back 112 bitcoins today, that would come to a bit over $2 million, a dollar interest rate of over 2,400 percent. (If you'd borrowed ether you'd be paying over 12,000 percent.) Unless your working capital was bitcoin, you will not be able to pay back that loan. The lesson here is: Probably don't borrow an asset caught in a massive speculative frenzy to fund your working capital needs.
Poloniex is an asset exchange based in the US. Trading on Poloniex is secure and allows traders to explore new and trendy coins which are up for speculation. It offers high volume margin trading and lending service for major crypto assets. Reportedly, the largest user base for trading on this site comes from Russia (6.06%) and US (24.84%). A differentiating factor about the site is that it does not support fiat currency.

The Fund will issue and redeem shares only to Authorized Participants (typically, broker-dealers) in exchange for the deposit or delivery of a basket of assets (securities and/or cash) in large blocks, known as Creation Units, each of which is comprised of [                ] shares. Retail investors may only purchase and sell Fund shares on a national securities exchange through a broker-dealer. Because the Fund’s shares trade at market prices rather than NAV, shares may trade at a price greater than NAV (a premium) or less than NAV (a discount).

The Funds may invest in foreign issuers, securities traded principally in securities markets outside the United States, U.S.-traded securities of foreign issuers and/or securities denominated in foreign currencies (together “foreign securities”). Also, each Fund may seek exposure to foreign securities by investing in Depositary Receipts (discussed below). Foreign securities may involve special risks due to foreign economic, political and legal developments, including unfavorable changes in currency exchange rates, exchange control regulation (including currency blockage), expropriation or nationalization of assets, confiscatory taxation, taxation of income earned in foreign nations, withholding of portions of interest and dividends in certain countries and the possible difficulty of obtaining and enforcing judgments against foreign entities. Default in foreign government securities, political or social instability or diplomatic developments could affect investments in securities of issuers in foreign nations. In addition, in many countries there is less publicly available information about issuers than is available in reports about issuers in the United States. Foreign companies are not generally subject to uniform accounting, auditing and financial reporting standards, and auditing practices and requirements may differ from those applicable to U.S. companies. Further, the growing interconnectivity of global economies and financial markets has increased the possibilities that conditions in any one country or region could have an adverse impact on issuers of securities in a different country or region.
(a) derive in each taxable year at least 90% of its gross income from (i) dividends, interest, payments with respect to certain securities loans and gains from the sale or other disposition of stock, securities or foreign currencies, or other income (including but not limited to, gains from options, futures, or forward contracts) derived with respect to its business of investing in such stock, securities or currencies, and (ii) net income derived from interests in “qualified publicly traded partnerships” as described below (the income described in this subparagraph (a), “Qualifying Income”);
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: