Maintenance Margin - this is the % of the position value you have to have in your account at the very minimum to avoid being Margin Called.  In some exchanges, margin call will mean you get notified and must deposit more margin to avoid liquidation (like CryptoFacilities). On other exchanges you will at this point be liquidated out of your position. So if maintenance margin is 5%, then the 0.05 BTC of your initial margin will need to be kept for the position to be alive.

In general, a foreign corporation that is not engaged in and is not treated as engaged in a U.S. trade or business is nonetheless subject to tax at a flat rate of 30% (or lower tax treaty rate), generally payable through withholding, on the gross amount of certain U.S.-source income that is not effectively connected with a U.S. trade or business. There is presently no tax treaty in force between the United States and the jurisdiction in which any Subsidiary is (or would be) resident that would reduce this rate of withholding tax. Income subject to such a flat tax is of a fixed or determinable annual or periodic nature and includes dividends and interest income. Certain types of income are specifically exempted from the 30% tax and thus withholding is not required on payments of such income to a foreign corporation. The 30% tax generally does not apply to capital gains (whether long-term or short-term) or to interest paid to a foreign corporation on its deposits with U.S. banks. The 30% tax also does not apply to interest which qualifies as “portfolio interest.” Very generally, the term portfolio interest includes U.S.-source interest (including OID) on an obligation in registered form, and with respect to which the person, who would otherwise be required to deduct and withhold the 30% tax, received the required statement that the beneficial owner of the obligation is not a U.S. person within the meaning of the Code.
There are two "types" of bitcoin -- Quanto and Inverse. Vast majority of bitcoin futures contracts are INVERSE, not Quanto. This means that the PNL is smoothed in USD terms, so that the contract value is maintained through price fluctuations. Put simply, it allows you to make a perfect USD-value hedge when you short with Bitcoin, which makes it ideal for speculators and hedgers. This means that if the BTC/USD value drops 1% you will earn more raw BTC than if it increases 1%. This is because when the price is falling, the USD value of the BTC is also falling, so the payout mathematically adjusts for this and increases as the price falls, compensating for the reduced USD value.
A Fund’s current obligations under most swap agreements (total return swaps, equity/index swaps, interest rate swaps) will be accrued daily (offset against any amounts owed to the Fund) and any accrued but unpaid net amounts owed to a swap counterparty will be covered by segregating or earmarking cash or other assets determined to be liquid, but typically no payments will be made until the settlement date. In connection with CDS in which a Fund is a “buyer”, the Fund will segregate or earmark cash or assets determined to be liquid by the Advisor, with a value at least equal to the Fund’s maximum potential exposure under the swap (e.g., any accrued but unpaid net amounts owed by the Fund to any clearinghouse counterparty). In connection with CDS in which a Fund is a “seller”, however, the Fund will segregate or earmark cash or assets determined to be liquid by the Advisor, with a value at least equal to the full notional amount of the swap (minus any variation margin or amounts owed to the Fund under an offsetting cleared transaction). This segregation or earmarking is intended to ensure that a Fund has assets available to satisfy its potential obligations with respect to the transaction. Each Fund reserves the right to modify its asset segregation policies in the future, including modifications to comply with any changes in the positions articulated by the SEC or its staff regarding asset segregation. Swap agreements that cannot be terminated in the ordinary course of business within seven days at approximately the amount a Fund has valued the asset may be considered to be illiquid for purposes of the Fund’s illiquid investment limitations.

Ethereum (ETH) is more than just a currency – it’s like one giant computer housing many computers around the globe. Ethereum can respond to sophisticated requests. Its ability to store revolutionary computer programs, known as smart contracts, gives Ethereum an edge over Bitcoin and has attracted attention from banks around the world. This, among other factors, has led to a jump of almost 10,000% in 2017!
There are so many hoops to jump through to set up for mining and each coin has its quirks. The power of your machine and graphix card and your power consumption are all important. My friend mined for 8month Eth and only made couple of hundred bucks by time you subtract power useage etc. He already had a powerful machine used in film industry for video graphix just sitting around so he thought he’d put it to use over that time for a laugh and see what happened. It took many hours messing around to set up and occassionally nursing it over that period. Of course he had to use his machine also occassionally which compromised the performance.
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.