A group of New York City homeowners has sued Mayor Zohran Mamdani and the city’s finance director over the rollout of the new pied-à-terre tax. Petitioners Simon Hedley, Rachel O’Brien, and Carmine Morano allege the city incorrectly identified their primary residences as potentially subject to the surcharge.

While the lawsuit does not challenge the legality of the surcharge itself, it scrutinizes the release of a tax roll containing names and addresses of over 900,000 homeowners. Many of these individuals were not subject to the tax. The city's Department of Finance noted that while the roll includes various units, the vast majority are not subject to the surcharge.

Represented by Randy Mastro, the plaintiffs are seeking to have the notices and property roll declared unlawful and removed from public view. The pied-à-terre tax targets non-primary residences valued over $5 million or co-ops valued at $1 million or more. Following significant backlash, Mayor Mamdani announced that the deadline to prove primary residency has been extended until September 18.