Using software that links him directly to Nasdaq marketmakers and a private trading system called Island, Milman checked further.

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Levine and Citron dubbed their new private trading system Island.

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Dark pools are a private or alternative trading system that allows participants to transact without displaying quotes publicly.

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This mutual exchange concept is expanded more broadly in the LETS (Local Exchange Trading System) model of private currencies.

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Malcolm Bendle, the Longtown company secretary, maintains that the market's book-keeping system is so meticulous that private trading is impossible.

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Definition of private equity: a marvelous system for creating wealth by trading an existing stock of assets back and forth at ever higher prices.

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It also let private trading systems called ECNs (electronic communications networks) post their prices on the same system.

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