Ratings and research firm Standard & Poor’s said Monday it has agreed to merge its valuation services unit with Duff & Phelps, a financial advisory and investment banking firm, for an undisclosed sum.

Standard & Poor’s, a unit of publishing house McGraw-Hill Cos., said it aims to focus on its core business of providing independent research, ratings and indices. It expects to close the sale late this month.

While the company didn’t disclose financial terms of the deal, it said it would sell the business to an investor group and the management of its unit. Vestar Capital Partners and Lovell Minnick Partners are providing financial backing for the deal. General Electric Capital Corp. is also providing debt financing.

McGraw-Hill shares were down 44 U.S. cents at US$47.46 in afternoon trading on the New York Stock Exchange.