Mamdani’s and New York’s pied-à-terre tax isn’t a socialist scandal: It’s unsexy tax policy with 200-year-old public records

Every January, New York City’s Department of Finance (DOF) does the same unglamorous thing it’s done for nearly 200 years: it puts a value on every property in the five boroughs and writes it down where the public can see it. The requirement traces back to 1830, when New York made recording property ownership mandatory statewide. In essence, for nearly 200 years, a nosy New Yorker could look up the value of their neighbor’s house, and that’s because New York has never treated property ownership as private: it’s a public record.

But that wasn’t the reaction to the publication of a supplemental roll by the DOF a “rich tax” dragnet, a doxxing operation, a “hit list.” Citadel’s Ken Griffin said he felt doxxed and called New York City Mayor Zohran Mamdani’s April video, filmed outside his own $238 million Central Park South penthouse, a “dangerous” stunt—even though his purchase price, city valuation, and ownership have sat in the same public files for years. Nothing in the file was secret.

The DOF took two things it already tracks separately: assessed value, and which properties might not be a primary residence, and put them in one spreadsheet. Combining two already-public columns on an Excel file isn’t a breach. But the uproar does reveal a lot about the supposed socialist takeover of New York City.

What’s the hubbub about?

On July 24, DOF posted two new files to its property assessments page: a supplemental roll for Tax Class 1 (with 684,619 properties) and one for Tax Class 2 (275,091 properties), making a 959,710 combined, a subset of the city’s full 1,048,576-row assessment roll across Classes 1 through 4. The city was legally required to publish the files by July 25 ahead of the tax’s implementation. The only new thing to the public realm is the imputed valuations for roughly 36,700 individual co-op units, almost all in Manhattan, which is data the DOF has never published before, since co-ops are normally assessed at the building level. (Most of these co-ops don’t clear the thresholds for pied-à-terre tax and therefore are not included in Fortune’s analysis).

When this native New Yorker and avid ACRIS user (the city’s automated City Register that let’s you search property records) went through the new supplemental roll, it quickly became apparent why there was so much public outcry and confusion surrounding the tax.

For starters, neither file is filtered beyond building classification code. (Some coverage seized on that, pointing to modest homes on Chaffee Avenue in Throggs Neck and Challenger Drive on Staten Island as proof the list swept up working-class New Yorkers). The unfiltered file also caught properties that plainly wouldn’t qualify: the embassies of Italy (worth $52.5 million at 690 Park Avenue), Indonesia (worth $57.7 million at 5 East 68th Street), and the UAE (worth $51.6 million at 39 East 74th Street), plus large LLC-held trophy properties all wouldn’t be subject to the tax. Reporters found DOF Commissioner Richard Lee’s own Flushing home and a Park Slope rowhouse owned by former Mayor Bill de Blasio in the same unfiltered file, alongside Griffin, Joe Tsai, Anna Wintour, Woody Allen, Martin Scorsese, and Spike Lee, but none of which means they owe the........

© Fortune