The billionaire's firm won the landmarked Argonaut Building in a 2024 foreclosure auction and now plans to vacate its grant-making tenant.
George Soros's Soros Fund Management has put the landmarked Argonaut Building, a roughly 140,000-square-foot office and retail property at 224 West 57th Street in Midtown Manhattan, on the market for about $100 million, according to a source with knowledge of the sale. Newmark brokers Adam Spies, Adam Doneger and Willis Robbins are marketing the building.
The 1909-built structure between Broadway and Seventh Avenue is fully occupied by Soros's grant-making group the Open Society Foundations, which moved into the building in 2013 and has a lease running through 2042. TD Bank is a retail tenant on the ground floor.
Soros won the property in a foreclosure auction after filing suit in April 2024 against former landlord eretz group, citing a default on a $145 million mortgage, The Real Deal reported at the time. Eretz had purchased the site for $213.8 million in 2015.
The billionaire plans to move his grant-making group from the building once a deal is closed, according to The Real Deal. A Newmark offering memo described the sale as a rare opportunity to reposition the historic building into residential apartments, the publication reported.
The property has additional air rights that could give it a total buildable space of more than 200,000 square feet, according to The Real Deal. If an office-to-residential conversion proceeds at the West 57th Street building, it would join another conversion project nearby at 135 East 57th Street, where TF Cornerstone is turning the former office building into 350 apartments.
Newmark declined to comment. A spokesperson for Open Society Foundations did not immediately respond to a request for comment.
The Deployment Angle
Family Office Real Estate Daily Desk · our analysis, not the source's
A family office considering this opportunity faces a choice between two paths. One is acquiring the building with the existing tenant in place and pricing in twenty years of below-market cash flow from an affiliate lease. The other is underwriting a conversion to residential condominiums or rental apartments, which the broker markets as the higher-value route.
The residential play hinges on the air-rights buildable. The source text states the property could reach more than 200,000 square feet of total buildable space. That implies roughly 60,000 square feet of unused development rights atop the existing 140,000-square-foot structure. A buyer would need to price demolition or gut renovation of the landmark, zoning compliance for the conversion, and the construction cost for the incremental air rights. At current Midtown residential pricing, that arithmetic determines whether the $100 million ask leaves margin.
The seller's position complicates the deal. Soros won the building in foreclosure after the prior owner defaulted on $145 million of debt against a $213.8 million basis from 2015. If Soros is selling at $100 million, he is either clearing a foreclosure recovery at a steep discount to the original loan or writing off the property as a distressed exit. Either way, a buyer is inheriting a building the prior capital structure could not carry.
The cleanest deployment route is a direct purchase paired with pre-negotiated tenant surrender from Open Society Foundations and immediate conversion plans. A co-investment with an experienced Midtown residential developer sidesteps the family office's need to staff the project itself. An LP commitment to a conversion fund that takes this building among others spreads the execution risk. Avoid buying the building with the tenant in place unless the lease economics clear a market return without the conversion upside, which the pricing suggests they do not.
