(The Center Square) — New York City Mayor Zohran Mamdani's new tax on second homes has drawn its first legal challenge from a group of property owners who say it created confusion among residents who could be hit by the new levy.

In the legal challenge, filed in the state Supreme Court on Friday, several Manhattan property owners claimed that the city's decision to release a list of nearly 1 million properties that might be subject to the new pied-à-terre tax set off a "panic" among homeowners. 

The lawsuit doesn't challenge the underlying law requiring the tax — which was approved by the state Legislature and Gov. Kathy Hochul — but asks a state judge to declare that notice and another one sent to about 17,000 property owners "null and void" and force the city to notify only property owners that are subject to the tax. 

"In rolling out these two notices, the city has arbitrarily and capriciously foisted onto New York City residents the burden of proving they are not subject to the surcharge," the plaintiff's attorney, former New York City legal counsel Randy Maestro, who served as an aide for former mayors Eric Adams and Rudy Guiliani, wrote in the 22-page complaint. 

A Mamdani spokesperson said in a statement that the city’s Law Department will “vigorously defend" against the lawsuit and that the city has been working to provide information to property owners about the new tax. 

"The pied-a-terre surcharge will help deliver the city New Yorkers deserve: cleaner parks, safer streets and critical public investments that make our city a more affordable place," the statement said. "As the mayor has said, we also know that whenever government asks something new of New Yorkers, we have a responsibility to make the process clear, transparent and accessible."

The new tax calls for charging eligible property owners a 4% surcharge on one- to three-family second homes valued over $5 million and on co-ops and condos valued at $1 million.

The Mamdani administration estimates the levy will drum up more than $500 million a year for the city to help plug gaps in the budget and fund the mayor's lefty agenda.

Mamdani has defended the tax, saying it will only impact the “richest of the rich,” sitting on empty properties as they "reap the huge financial rewards" of holding real estate in New York City.

But the levy is part of Mamdani's "tax the rich" campaign which has prompted outrage from wealthy Manhattan property owners, including Wall Street billionaire Ken Griffin, who threatened to pull his company Citadel out of a skyscraper project in the city after the mayor filmed a video outside of his home.