SL Green Realty Corp. (NYSE: SLG) signed a 64,077 square foot lease with Sigma Computing, Inc. for a portion of the 3rd floor at One Madison Avenue, according to a company statement. The lease brings the property to 78.1% leased.

The Manhattan-based real estate investment trust has signed office leases totaling 1,260,707 square feet in Manhattan in 2025, with a current pipeline of approximately 1.0 million square feet.

"We're excited to welcome Sigma Computing to One Madison Avenue where they join a sterling tenant roster that includes IBM, Franklin Templeton, Coinbase, Flutter Entertainment and Palo Alto Networks," said Steven Durels, Executive Vice President and Director of Leasing and Real Property at SL Green.

One Madison Avenue is located overlooking Madison Square Park and was designed by architect Kohn Pedersen Fox. The building features a HVAC system that circulates 100% fresh air, floor-to-ceiling windows, and amenities including Le Jardin Sur Madison event space, La Tête d'Or by Daniel restaurant, a 7,000 square foot tenant lounge called The Commons, and Chelsea Piers Fitness.

Sigma Computing was represented by Brent Ozarowski of Newmark, while SL Green was represented by Paul Glickman, Alex Chudnoff, Ben Bass and Diana Biasotti of JLL.

As of June 30, 2025, SL Green held interests in 53 buildings totaling 30.7 million square feet, including ownership interests in 27.2 million square feet of Manhattan buildings and 2.7 million square feet securing debt and preferred equity investments.