Fortis Property Group is a privately held real estate investment and management company based in Brooklyn. Founded in 2005, Fortis has developed upwards of $3 billion in commercial real estate, mainly Class-A office space and retail, as well as multifamily residential throughout New York City and Boston, as well as projects in Connecticut, Virginia and Texas.

While many of Fortis' holdings are office buildings, the firm has shied away from office space in Manhattan, preferring to focus instead on residential spaces downtown and in Brooklyn. Most of the firm's funding comes from senior and mezzanine debt, but it also has several high-net-worth individuals and institutions that invest with the firm.

Some of Fortis' projects have met with pushback, such as the 2015 plans to develop Long Island College Hospital in Brooklyn (Fortis bought the property the previous year for $240 million), which received backlash for the lack of affordable housing.

Fortis also was sued by Jack Resnick & Sons in a trademark dispute over Fortis' use of the "One Seaport" name to market a condo tower at 161 Maiden Lane near South Street Seaport, but the dispute was settled in 2015 with Fortis agreeing to market its 58-story luxury condo development as "1 Seaport."

The naming dispute wasn't the last trouble to hit the 161 Maiden Lane project. In 2017 work on the building was stalled after the death of a construction worker. Then in 2019, Fortis discovered that the tower was leaning three inches to the north, and traded blame and lawsuits with one-time contractor Pizzarotti. And in 2020, Bank Leumi USA announced it's intention to foreclose on the property over $120 million in loans.