Phillips Auction House Inks 23K-SF Deal at 950 Third Avenue

Auctioneers Phillips Auction House has hammered out a 23,000-square-foot lease as part of two new deals signed at 950 Third Avenue in Midtown East, Commercial Observer has learned. 

Phillips secured the largest space out of the two leases at the 32-story office tower between East 57th and East 58th streets, with landlords Naomi and Andre Altholz handing out a total of 30,000 square feet in new deals.

The auctioneer’s new space occupies the entire 14th and 15th floors inside the Class A office tower. It’s unclear whether the deal represents a new location or a relocation for Phillips, which has a current global headquarters at 432 Park Avenue, one of  its 13 worldwide locations, according to its website.

Phillips did not respond to a request for comment, so it’s also unclear whether the company had outside representation in the deal. Newmark’s Jared Horowitz, John Cilmi and William Grover negotiated on behalf of the landlords. 

The asking rent was not disclosed, but Midtown’s office asking rent averaged $84.77 per square foot in April, according to data from CBRE.

Phillips’ April lease coincided with the arrival of private capital investment firm Backcast Partners at 950 Third Avenue. The investment management firm signed on for 7,000 square feet on the 20th floor, according to Newmark.

In addition to 950 Third Avenue, Backcast hosts a second office location in Millburn, N.J. Backcast did not respond to a request for comment, and its representation in the deal is also unknown.

A wave of new leases at 950 Third Avenue over the past several quarters have totaled a collective 55,000 square feet, according to Newmark. Fourth-quarter arrivals in 2025 included developer Olnick Organization, payment technology provider Boost Payment Solutions and artificial intelligence-powered hiring platform Meytier. 

Emily Davis can be reached at edavis@commercialobserver.com.