Nasdaq OMX posted a surprise 3.7% increase in fourth-quarter profit, boosted by units that provide corporate services to companies and that handle derivatives trades.

The company has been aggressively expanding its business of late, reducing dependence on trading activity amid a multi-year decline in stock-trading volume. In December, Nasdaq agreed to pay $390m for Thomson Reuters' investor-relations, public-relations and multimedia-services businesses, bolstering a growing corporate-solutions unit.