Bequant employs a 'maker-taker' model for fees, with the purpose of maximising liquidity and narrowing the spread on our markets, as well as encouraging market-makers.
In a maker-taker model the "taker" is a trader who removes the liquidity from the book by placing an order that matches immediately with an existing order on the book. The Taker pays the fee from the committed trade.
The "maker" is a trader who provides liquidity to the order book by placing a limit order below the best ask price for buy and above the best bid price for sell.
If current sell price for BTC is 10,000 USDT and you place a buy order at 10,000 USDT, your order will be executed immediately. In this case you are acting as a taker and hence will be charged the taker fee of 0.1%.
If current sell price for BTC is 10,000 USDT and you place a limit buy order at 9,950 USDT, you are acting as a maker and hence will be charged the maker fee of 0.01%.