(The story has been updated to include additional information about the merger.)

CHICAGO and NEW YORK CITY—Cushman & Wakefield and DTZ said early Monday that they had reached a definitive agreement to merge, with DTZ's parent company TPG Capital paying $2 billion to buy C&W from majority owner Exor SpA, including the assumption of debt. GlobeSt.com first reported three weeks ago that a possible deal was in the works.

Brett White, formerly CEO of CBRE, will combine chaiman and CEO of the combined company. He says C&W and DTZ have “remarkably complementary skills and reach in different geographies. Whether in New York, London or Shanghai, this will be a formidable combination.”

He adds, however, that although “breadth and depth are important to serve clients, it's not just about size. It's also about local expertise and deep customer service, which are strong traits of Cushman & Wakefield and DTZ, and ultimately what will differentiate us going forward.”

The new company will operate under the Cushman & Wakefield brand. It will have an employee base of more than 43,000 employees worldwide, annual revenues of $5.5 billion and a portfolio of more than four billion square feet under management for institutional, corporate and private clients.

David Bonderman, TPG's founding partner, says that "the potential created by this combination would not have been possible without Exor's support and positioning of Cushman and Wakefield over the last eight years. Exor has achieved great success in growing a business that is performing extremely well, and once combined with DTZ, will be even better positioned to further capitalize on the real estate growth trends across the globe.”

He adds that C&W is “one of the strongest brands in the global real estate business, and we are delighted to have the opportunity to share in the expansion of this great company.” A consortium led by Fort Worth-based TPG acquired DTZ and Cassidy Turley in 2014, formally merging the two companies this past January.

For Exor. the Torino, Italty-based investment company controlled by the Agnelli family, the C&W sale to the TPG-led group will generate net proceeds of $1.278 billion, representing a capital gain for Exor of approximately $722 million. Exor has held a controlling stake in C&W since 2007.

"It gives us great satisfaction to see a business we have owned for many years become part of a new powerhouse in the sector as it approaches its centennial year, reinforcing its prospects for even greater success in the future,” says John Elkann, chairman and CEO of Exor. The sale is expected to close in the fourth quarter.

Post-merger, Carlo Barel di Sant'Albano, current international CEO of C&W and its EMEA CEO, will take an unidentified senior global leadership role. John Santora, C&W's current CEO of North America, will become COO and chief integration officer. Tod Lickerman, currently global CEO of DTZ, will assume the role of president of the itengtrated company.