Can a NYC apartment building ban signs or flags in windows?

You probably noticed more signs and flags in New York City apartment windows in the past few years—political campaign signs from recent elections, Black Lives Matter flags, and even Cancel Rent banners. Can there be consequences if you hang flags or signs with these messages in your apartment window? For example: Can your building ask you to take it down?
It really depends on what the message is and where it’s hung. That’s because most residential buildings—rentals, co-ops, and condos—have their own house rules on what you can and cannot do, including in common areas and even your apartment windows.
For example, in 2018, a Manhattan judge ruled that a Midtown condo resident had to take down an American flag hanging out of his window, according to the New York Post. The ruling was based on the fact that he was violating his building’s rules on putting anything in common areas.
Steven Wagner, a partner at the Manhattan law firm Wagner, Berkow & Brandt (a Brick sponsor) worked with a co-op resident in a similar situation. The ground-floor resident drilled and installed an American flag and two lights on the facade of the building. The co-op requested it to be removed because it was on their property, Wagner says. The resident vowed not to take it down until every American soldier returned from overseas—but eventually he had to remove it because it was considered damaging to the property.
Here’s what else you should consider when hanging flags or signs in your apartment windows—and when your building can rightfully ask for it to come down.
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