How EXPIRY reads the dates
EXPIRY shows what the FDA lists. It does not tell you when a generic will launch.
Where the data comes from
The FDA publishes the Orange Book as three data files: products, patents and exclusivity. EXPIRY joins them by application and product number. The page shows the date the data was last refreshed. Biologics (the Purple Book) are not included yet.
The dates on a drug page
- Substance patent: the latest listed patent that covers the active ingredient.
- Product patent: the latest listed patent that covers the formulation or product.
- Core protection: the later of those two.
- Use patents: the latest listed patent tied to a method of use. These can often be avoided by a generic that leaves that use off its label, so they are shown with less weight.
- Exclusivity: the latest listed FDA exclusivity date.
- Latest listed protection: the latest date of any kind.
Dates already in the past are left out of these headline dates. Each patent is counted once, even when it covers several strengths.
When exclusivity is not listed
The FDA file lists exclusivity only while it is running. A drug with none listed has either finished its exclusivity or never had any. For brand drugs approved more than 5 years ago, EXPIRY adds a note that standard 5-year new-chemical exclusivity would have ended around that date. That note is an estimate. It is never used in the headline dates or in sorting.
What the dates do not show
- Generic launch dates. Court cases, settlements, pediatric extensions and patent term changes can move the real date.
- Patent titles. The Orange Book does not include them.
- Patents that were never listed with the FDA.
Always check the FDA record and a patent attorney before you rely on a date.