BlackRock Inc. (BLK) today reported fourth-quarter income of $657 million, or $3.35 a share, excluding items, up $401 million from a year ago and $106 million higher than the third quarter. “We closed 2010 with strong earnings for the quarter and the year, attractive investment performance and growing new business momentum,” said CEO Laurence Fink. “Away from merger-related outflows, new business was robust, with a combined $96.6 billion in fourth quarter net flows and net wins in the pipeline.” The full year operating margin was 34.8%, which included $90 million of integration costs associated with the December 2009 acquisition of Barclays Global Investors. The fourth-quarter operating margin was 37.7%. “December 1, 2010 marked the one-year anniversary of our merger with BGI,” Fink said. “We accomplished a great deal during our first year, evolving our culture, organizational structure and governance model.” BlackRock offers investment management, risk management and advisory services for institutional and retail clients. It currently has $3.56 trillion assets under management. Write to Jacob Gaffney. Follow him on Twitter @JacobGaffney.