All the countries have laws regarding to financial transactions and they require a financial license for the Bitcoin exchangers. It doesn't matter if you are in USA or China.
If Bitcoin isn't defined as money in their country, exactly why would they need such a license? Bitcoin is still in the 'grey zone' for a lot of places.
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if however they are just swapping bitcoin for altcoins(no fiat at all). then and only then do they not need a licence.
Franky just so you know, according to the FinCEN docs that Mayax are providing, if you interpret them as he is,
then bitcoin for altcoin buy/sells or vice versa also requires a money transmission license.
Definitions of User, Exchanger, and Administrator
This guidance refers to the participants in generic virtual currency arrangements, using the terms "user," "exchanger," and "administrator."6 A user is a person that obtains virtual currency to purchase goods or services.7 An exchanger is a person engaged as a business in the exchange of virtual currency for real currency, funds, or other virtual currency. An administrator is a person engaged as a business in issuing (putting into circulation) a virtual currency, and who has the authority to redeem (to withdraw from circulation) such virtual currency. (Emphasis Added)
So, if they wanted to argue it, they could interpret it to say things like Poloniex or Shapeshift are also money transmitters.