We all know that dates – of any kind – can be critically important in our everyday lives. But in the lives of inventors and patent attorneys alike, dates can be everything. With such an important variable in the patent application process, it is important to understand that there are different classifications of “dates” in patent law. Let’s take a look at the two most important dates from the perspective of the patent application: the Filing Date and the Priority Date.
What is a Filing Date?
The Filing Date of a patent application is “the date on which a complete application is received in the Office,” per the USPTO’s Manual of Patent Examination Procedure. MPEP §2754. Once an application is received, the USPTO will notify any Applicant if the application is not complete, and the Applicant may then have an opportunity to correct the deficiencies by submitting the rest of the required component(s) of the application. The Filing Date, however, will be the date on which the final required component of the application is received at the USPTO, not the date on which the first components were originally filed (unless all components were filed together on the original date).
What is a Priority Date?
The Priority Date of a patent application is the date on which the inventor may rely for purposes of establishing its ownership rights to the invention. Priority Dates become extremely important in two circumstances: (1) when the present patent application is a member of the same “family” as older patent applications; and (2) when the present patent application is filed pursuant to the Patent Cooperation Treaty (“PCT”).
When there is a “family” of patent applications that pertain to a single invention or derivatives or continuations of an invention, the Priority Date of all patent applications in the family is generally the same date. This is usually the Filing Date of the “parent” application that disclosed the original invention.
The Priority Date of an application that was not originally filed in the U.S. may very well be earlier than the Filing Date on which the application is received by the USPTO. Under the PCT, the Priority Date of a U.S. application is the Filing Date on which the original underlying application was filed in another jurisdiction that is a party to the PCT.
Currently, 158 countries are party to the PCT, and this is the framework under which most international patent applications are submitted to a foreign jurisdiction. Some notable countries that are not party to the PCT include Argentina, Pakistan, Taiwan and Venezuela.
In 2024, applications originating China, the U.S., and Japan accounted for over half of all patent application filings under the PCT, making it a standard framework for securing patent rights internationally in most developed countries. This means that securing your earliest Priority Date in one of these PCT countries can be critical to securing your international rights to your invention.
Illustrative Example
If First Inventor filed a patent application in the European Union on January 1, 2025, but did not file all of the components of a non-provisional utility application in the U.S. until April 1, 2025, the Inventor’s Priority Date would still be January 1, 2025.
Now let’s say that Second Inventor filed a complete non-provisional application in the U.S. for the same invention on February 1, 2025, and this is the first time that Second Inventor has filed an application for the invention anywhere in the world.
Who has the senior rights to this invention, when First Inventor’s U.S. Filing Date is April 1 and Second Inventor’s U.S. Filing Date is two months earlier?
Answer: First Inventor. This is because First Inventor secured the Priority Date that established his rights to the invention a month earlier than Second Inventor’s Priority Date. In this example, the Second Inventor’s Filing Date is the same as his Priority Date, while First Inventor’s Priority Date is three months earlier than his U.S. Filing Date.
Contact Sand, Sebolt & Wernow
If you need a patent attorney, Sand, Sebolt & Wernow is an intellectual property law firm. We specialize in patents, trademarks, copyrights, IP (intellectual property) litigation licensing, foreign filings and trade secrets. We’re also innovators, just like you. Our staff includes attorneys, patent agents and engineers with experience in electronics, mechanics, software, hardware and robotics. Contact us.