The Rockefeller Group is an American private company based in New York City, primarily involved in real estate operations in the United States. It is a subsidiary of Mitsubishi Estate Co. The company began with the development of Rockefeller Center.
After building the original 6,000,000-square-foot (560,000 m2), Art Deco complex from 1931 to 1939 (the company name was then the Metropolitan Square Corporation), the company developed several towers in the immediate vicinity from the late 1940s into the 1950s and 1960s. It entered into a partnership with Time Inc. and constructed a 48-story building for the company that opened in 1959; this spearheaded the expansion of the Center to the west of 6th Avenue, Avenue of the Americas. By the early 1970s, it had added a total of four International Style towers to Rockefeller Center, more than doubling the size of the original complex.
Today, The Rockefeller Group maintains an ownership/management position in the 7,700,000 square feet (720,000 m2) of office space that makes up Rockefeller Center’s western corridor (the newer buildings located west of Sixth Avenue). The eastern and original part of the Center is now owned by Tishman Speyer (who also serves as manager) and the Lester Crown family of Chicago, Illinois.