NEW YORK CITY-The Open Society Foundations has signed on to become the full-building office tenant at the Argonaut Building, located at 224 W. 57^th St. An Open Society Foundations spokesperson tells GlobeSt.com that the group, founded by billionaire George Soros, is growing--hence the doubling in size of office space. It will move from its current address, at 400 W. 59^th St., sometime in the third quarter of 2012.

“It is hard to believe that, while the Argonaut Building is one of the city’s oldest buildings, the Open Society Foundations will now become only the third company to have worked behind its walls over the past 102 years,” says Colliers International vice chairman Brian Given in a prepared statement. Given represented the landlord, M1 Real Estate, along with several colleagues--Michael Cohen, president of the Tri-State Region and executive managing directors Robert Bakst and Robert Sass. M1 Real Estate, based in Monaco, is a real estate development and investment company and an affiliate of M1 Group.

The Argonaut Building was designed by architect Francis Kimball and built in 1909, receiving New York City Landmarks designation in 2000. Substantial renovations, including improvements to HVAC, plumbing and elevators cabs, were completed in 2009.

Eric Deutsch at CB Richard Ellis represented the Open Society Foundations in the 30-year lease, along with James Coleman and Steve Kaufman of Hanley Advisors. The OSF will take the entire building in the lease, save a portion of the ground floor and retail space.

“M1’s commitment to the Argonaut Building never wavered, and this signed lease proves that their vision and understanding of the market was right on point,” Given says. “When we set out to market the property, we all agreed with M1 that the ultimate end user should be of a very high quality like George Soros and his foundations.”