Fimat, the prime broking arm of Société Générale, has agreed to acquire PreferredTrade, a US equity broker with 100 staff, to add US equity trading to its services for hedge funds.

The acquisition, understood to have cost Fimat "a few million dollars", has given the French prime broker membership of the American Stock Exchange; the New York, Pacific, Philadelphia and Boston stock exchanges; the Chicago Board Options Exchange; and the International Securities Exchange.