Patent expiry date Calculator for us patents

How to calculate patent expiry date for patent filed in United States of America (US).

First we have to check the application filing date: if the application filing date is prior to June 8, 1995 then follow Method-1; and if  the application filing date is on or after June 8, 1995 then follow Method-2.

Method: 1

* Add 17 years to the patent issue date (INID code: 45) and obtain the first date.
* Then add 20 years to the application filing date, in case there is non-provisional patent application in the patent family then add 20 years to the application filing date of the non-provisional patent application (INID codes: 62 or 63) to obtain the second date.
(*Note: Provisional applications (INID code: 60) are disregarded.
* If any terminal disclaimer or extension or adjustment to the patent term denoted by an asterisk and also published below the ‘Assignee’ information (INID code 73) is found then add that to the obtained dates.
* The later of the two dates (first date and second date) is the patent expiry date.

Method: 2

* Add 20 years to the application filing date, in case there is non-provisional patent application in the patent family then add 20 years to the application filing date of the non-provisional patent application (INID codes: 62 or 63) to obtain the patent expiry date.
(*Note: Provisional applications (INID code: 60) are disregarded.
* If any terminal disclaimer or extension or adjustment to the patent term denoted by an asterisk and also published below the ‘Assignee’ information (INID code 73) is found then add that to the patent expiry date
.
Or else just click on this link and enter the dates. :-)