OKCoin is a Bitcoin company in China with core product lines of a Bitcoin exchange, and a mobile consumer payment and lending app. OKCoin Exchange China operates CNY/BTC spot pair with margin trading from its Beijing entity, while OKCoin International operates USD/BTC spot pair with margin trading and BTC/USD futures from its Singapore entity.
USD/BTC is not a spot pair,
( z1 pair :polarity - :mod ( z2 spot ) :domain ( z3 slash :op ( z4 dollar ) :op ( z5 thing :mod ( z6 string-entity :value "BTC" ) ) ) )