Thinking Machines Lab Leases 21,500 SF at 79 Fifth Avenue

Thinking Machines Lab Leases 21,500 SF at 79 Fifth Avenue

Artificial intelligence research startup Thinking Machines Lab has secured its first office in New York City, agreeing to a 21,500-square-foot lease at 79 Fifth Avenue. The location places the firm just one block west of Union Square in the Flatiron District.

The tenant will occupy the entire fourth floor of the 18-story building, which is owned by Kalimian Properties. While specific financial details regarding the lease were not disclosed, sources indicate that asking rents at the property are slightly above $100 per square foot.

Thinking Machines Lab was founded in early 2025 by Mira Murati, the former chief technology officer of OpenAI. The company focuses on designing specialized AI models and creating tools to help researchers and businesses train their own systems. Following a funding round led by Andreessen Horowitz in July 2025, the startup reached a valuation of $12 billion.

Representing the startup in the transaction were Justin Haber and Kyle Riker from Jones Lang LaSalle Incorporated. JLL’s stock recently closed at $386.08, reflecting a decline of 1.76% from the previous session. The landlord was represented by a team from Newmark, including David Falk, Daniel Levine, and Dylan Weisman.

79 Fifth Avenue, situated between East 15th and East 16th Streets, counts several major organizations among its tenants, including The New School, Capgemini America, and Hulu. Fashion retailer Free People operates on the ground floor.

What to watch

• Lease Terms: Specific rental rates and lease duration remain undisclosed.
• Tenant Expansion: Whether the rapid growth of Thinking Machines Lab necessitates further real estate expansion in NYC.
• Market Activity: Continued demand for premium Class A office space near Union Square.

Source: original release