space, excluding area taken up by closets, elevators, restrooms, and walls. Gypsum partitions on each of the office floors were attached to the mullions. The building was also constructed with air conditioning on each floor, as well as an automatic fire alarm system and mail conveyor system. The triple-story mechanical penthouse is atop the 21st floor and includes air-conditioning and elevator machinery, as well as a water tower. History Unilever was formed in 1929 from a merger of two soap companies: the British firm Lever Brothers Limited and the Dutch firm Margarine Unie. Unilever's United States subsidiary was known as Lever Brothers Company and was initially headquartered in Cambridge, Massachusetts. The subsidiary took space at 445 Park Avenue, three blocks north of the present building's site, in 1947. Development and early years The company began acquiring land on Park Avenue from 53rd to 54th Street around June 1949, leasing the lots from Robert Walton Goelet's estate. The negotiations were made secretively, involving fourteen sets of lawyers, numerous brokers, and several shell companies. As finalized, the lease was to run for sixty years. The main broker behind the transaction, S. Dudley Nostrand, won the award for the "most ingenious and beneficial Manhattan real estate transaction of 1949" from the Title Guarantee and Trust Company. On October 5, 1949, Lever Brothers announced a wide-ranging expansion program within the United States. The company's president, Charles Luckman, announced the executive offices would be moved from Cambridge to New York City that December, taking temporary space at two buildings in Manhattan. A new executive headquarters known as Lever House, to be built on Park Avenue from 53rd to 54th Street, would house the firm's subsidiaries upon its expected completion in late 1951. SOM was hired to design Lever House when it was announced. Luckman, who also held an architect's license, would assist with the design. Although SOM had prepared plans for slab-like buildings in Chicago for a Lever Brothers headquarters, the company decided upon a New York City headquarters because "the price one pays for soap is 89 percent advertising [...] and the advertising agencies of America were there." In designing Lever House, SOM focused on the fact that Lever Brothers wanted of office space all to itself. Luckman left Lever Brothers in January 1950, because of unspecified disagreements with British and Dutch executives of Unilever. Luckman went to design several buildings of his own,