The William Kaufman Organization’s (WKO)’s brand new, high-end pre-built office suites at 437 Madison Avenue are striking a chord with tenants, with two units totaling 7,889 s/f now leased.
In the first transaction, Darktrace Limited, a global cybersecurity firm, has signed a five-year 3,807 s/f lease comprising a portion of the 32nd floor at the 40-story, 850,000 s/f office building, which is situated between 49th and 50th Streets.

The location will serve as the company’s new Manhattan offices. Founded in 2013, Darktrace is headquartered in Cambridge, UK, and San Francisco, and has offices in Auckland, Boston, Chicago, Dallas, London, Los Angeles, Mumbai, New York, Paris, Seoul, Singapore, Sydney, Tokyo, Toronto and Washington, D.C.
Also signing is independent New York City-based investment bank, HT Capital Advisors, LLC, which is relocating within the building. The firm specializes in middle market merger and acquisition advisory throughout the US and globally. The company is moving from a portion of the 39th floor to a brand new 4,092 s/f unit on a portion of the 19th floor for a five-year term. The company has been headquartered at 437 Madison Avenue for over a quarter century.
Michael Lenchner, vice president and director of leasing at Sage Realty Corporation, the leasing and management division of WKO, represented the building’s ownership in-house in both transactions, along with a Jones Lang LaSalle leasing team of Frank Doyle, David Kleiner, Cynthia Wasserberger, Hayley Shoener and Harlan Webster.
Daniel Posy and Jason Roberts of Savills Studley represented Darktrace Limited, and there were no outside tenant representation brokers in the HT Capital Advisors transaction. Asking rents in the building range from $80 to $110 per square foot.
The pre-built spaces are located on the 19th, 28th 32nd and 34th floors and range in size from 2,893 rentable square feet to 6,402 rentable square feet. The units, which are currently under construction, feature new state-of-the-art reception areas with stone floors and sheet rock ceilings, private glass-walled offices, high-end pantries, new corridors and new restrooms, broadband internet connectivity, flexible floorplates and views of St. Patrick’s Cathedral and the Midtown skyline.
“We are proud to meet the needs of space users of all sizes, from large companies to boutique firms,” Lenchner said.
“437 Madison Avenue offers Plaza District prestige with Grand Central convenience, making it an ideal location for any company looking for a strong central location with state-of-the-art amenities, modern finishes and unparalleled services.”
The new leases for Darktrace and HT Capital come on the heels of the building’s ongoing, $60 million capital improvement program, which is nearing completion in spring 2016.
When the work is finalized, 437 Madison will boast entirely new infrastructure and amenities, including a private 8,870 s/f 15th floor “sky lounge” with skyline views.