Blackstone is planning an office expansion in New York City, which could result in the private equity firm leasing new space or expanding its current location.

In total, the firm is looking for about 1.5M SF, Bloomberg reports, citing an unnamed source. A new lease could mean the private equity giant leaving the headquarters it has occupied at 345 Park Ave. for three decades. Taking more space in the Rudin family-owned building is also a possibility, Bloomberg report, and Blackstone is also considering redeveloping an existing building.

Both Blackstone and Rudin declined to comment. Blackstone has about 1.1M SF of offices in Manhattan right now, per Bloomberg, though its office ownership in the city has been in flux of late. The company now owns a 49% stake in One Manhattan West, after closing on a deal this month that valued the 2.1M SF, 3-year-old building at $2.85B.

This week, it turned over the keys of 1740 Broadway, a 26-story office tower, to the special servicer on its $308M commercial mortgage-backed security. Two major tenants had left that building in recent years, with law firm Davis + Gilbert leaving for Rudin’s 1675 Broadway in 2019 and L Brands electing not to renew its 418K SF lease, instead moving to 55 Water St. in 2020.

A Blackstone spokesperson told Commercial Observer that that particular asset is facing a “unique set of challenges." The company’s plan to expand will come as welcome news to the New York City office market, which is facing a cloudy future. Manhattan’s office availability rate hit 17.4% last month, a new record, according to Colliers.