The buyers also include Stone Point Capital LLC and Geneva-based Edmond de Rothschild Group.

The offer represents a 19.2% premium to the closing price of Duff & Phelps shares on 28 December 2012, and 27.3% over the company’s volume weighted average share price during the 30 days ended 28 December 2012.

The merger agreement provides for a "go-shop" period commencing immediately and ending on 8 February 2013, during which Duff & Phelps, with the assistance of its financial and legal advisors, will actively solicit and potentially receive, evaluate and enter into negotiations with third parties that offer alternative transaction proposals.

The merger agreement provides for a break-up fee of approximately US$6.65 million if Duff & Phelps terminates the agreement prior to 8 March 2013, in connection with a superior proposal that first arose during the go-shop period.

The transaction has been approved by the Board of Directors of Duff & Phelps, following the recommendation of a transaction committee consisting of independent directors.

Olivier Sarkozy, managing director and head of Carlyle’s Global Financial Services group, said, "Regulatory demands, implementation of new accounting policies and requirements for increased corporate disclosure and third party validation provide significant growth opportunities for Duff & Phelps core products and services.

"We will harness Carlyle’s and Stone Point’s global networks while leveraging Duff & Phelps preeminent brand to foster growth in new geographies. Additionally, we believe the involvement of Pictet and Edmond de Rothschild Group will support the company’s initiatives to enhance its international presence and expand its Limited Partner client base."

The transaction is expected to close in the first half of 2013, subject to customary closing conditions — including the receipt of stockholder and regulatory approvals.