Inspection history the city stopped publishing
Katz's has been open since 1888, but the city's official record starts in 2023. Here is where the rest of that history went, and how we recovered it.
The rolling window
New York's Health Department only publishes restaurant inspections from a rolling three-year window. In its official documentation, the dataset covers citations from inspections conducted "up to three years prior to the most recent inspection for restaurants... in an active status."
Because this window slides forward every time a restaurant is inspected, older records drop off the city's API permanently.
This effect is larger than it sounds. Out of 31,000 establishments in the current dataset, only 12% have any visible record before 2023. Consider three restaurants that have served New York for over a century:
| Restaurant | Trading since | Official record starts |
|---|---|---|
| Katz's Delicatessen | 1888 | 2023 |
| P.J. Clarke's | 1884 | 2024 |
| Keens Steakhouse | 1885 | 2024 |
These places have been trading for well over a century. The official public dataset shows under three years of it, and those start dates move: each one is simply three years back from the last time an inspector called.
Getting it back
While the city drops older records from its live feed, public web archives kept them. The Internet Archive has captured full CSV exports of the city's inspection database since 2015. Because each snapshot contains its own rolling three-year window, combining a few of them reconstructs a full decade.
We merged three archival snapshots with the live data, matching records using CAMIS (City Agency Management Information System), which is the city's internal permit identifier. Reconstructing these records across snapshots yields significant missing history:
| Year | Official dataset | With the archive |
|---|---|---|
| 2017 | 181 | 14,164 |
| 2018 | 250 | 20,964 |
| 2019 | 250 | 23,553 |
| 2020 | 63 | 4,883 |
| 2021 | 100 | 4,693 |
| 2022 | 4,044 | 18,483 |
In total, this adds over 106,000 inspections across nearly 17,000 restaurants, extending records back to October 2013. The live dataset only covers about 84,000 inspections, so this archive more than doubles available records, giving 54% of restaurants deeper history.
This historical data includes over 1,700 Health Department closures and nearly 1,600 reopenings that are no longer published on the city's open data portal.
Is old data trustworthy?
Because health violations can be dismissed or modified on appeal, we needed to verify if older archived records remained accurate. The city specifies that public datasets include "sustained or not yet adjudicated" citations. If violations were frequently overturned months after an inspection, archived snapshots would list violations that the city later erased.
We tested this by comparing two data snapshots taken six months apart. Looking specifically at 2022 inspections, which were recent enough that they could not have been dropped by the rolling three-year window:
| Outcome | Inspections | Share |
|---|---|---|
| Still present six months later | 24,273 | 95.8% |
| Gone, the restaurant had closed | 1,067 | 4.2% |
| Gone, restaurant still listed | 3 | 0.01% |
Out of more than 24,000 records, only three inspections disappeared while the restaurant remained open. Retroactive removals happen, but they are extremely rare. Nearly all dropped records are caused by business closures rather than changed inspection results.
We display these historical records with an explicit note: historical data provided as a snapshot at a point in time, adjudication status unknown. These older records are never factored into our scores, since every scoring window on our site uses data under three years old. How the score is built.
How permits hide restaurant history
A restaurant permit is tied to a corporate entity, not a physical dining room. Take Keens Steakhouse at 72 West 36th Street as an example:
| Source | Identifier | Name and address |
|---|---|---|
| Archives, to 2023 | 40373656 | KEENS STEAKHOUSE, 72 WEST 36 STREET |
| Live, from Dec 2024 | 50162845 | KEENS STEAKHOUSE, 72 WEST 36 STREET |
The name and address are identical, but the identifier changed. When a restaurant updates its ownership or legal entity, the city issues a new CAMIS permit number, resetting the visible inspection history to zero.
Because of this system, seeing "no history before 2024" on an official record can simply mean a restaurant updated its corporate permit, not that it recently opened. Neither the official street placard nor the city's online lookup makes this distinction.
It is also the one gap our archive cannot close. We keep older records for permits the city still lists, so when a permit is retired its history leaves the city's roster and ours at the same time. Keens is its own example: the decade we recovered covers most of the city, and for this restaurant it is empty.
Why this matters when choosing where to eat
A single clean inspection grade on a window placard tells you how a kitchen looked on one specific afternoon. It does not show whether a restaurant has maintained high standards for years or repeatedly closed for health violations under different permit numbers.
Recovering a decade of dropped records shows the long-term patterns a rolling window hides: whether a kitchen has held its standard for years, or been closed and reopened more than once. What it cannot do is follow a restaurant across a change of permit. So a blank history line most often means the city stopped publishing, not that the kitchen is new, and knowing which of those you are looking at is worth having before you walk through the door.