New York City's tax on second homes is now in effect after backlash from billionaires, including the Citadel CEO.

Citadel CEO Ken Griffin became the face of the tax after New York City Mayor Zohran Mamdani posted a video in front of Griffin's penthouse apartment.

A new tax will officially hit ultrawealthy property owners with crash pads or vacation homes in New York City.

Citadel CEO Ken Griffin doesn't approve of New York City Mayor Mamdani's pied-à-terre tax. See all the homes he owns around the country — and the world.

New York City's tax on second homes is now in effect after backlash from billionaires, including the Citadel CEO.