Private equity firm Permira said Wednesday that it will buy corporate finance adviser Duff & Phelps for $1.75bn from a group of buyers that includes Carlyle.

Duff & Phelps is known mainly for its valuation services to government entities, hedge funds and public companies. The company was a valuation adviser to the examiner in the bankruptcy of Lehman Brothers Holdings. It also provided valuation advice to the US Congressional Oversight Committee’s Troubled Asset Relief Program effort.