Legal Definitions - parent filing date

Definition: The date when a patent application is considered to have been filed. It is also known as the effective filing date.

Examples:

• John filed a patent application on January 1, 2021. Later, he filed a continuation application on June 1, 2021, claiming priority to the earlier application. The parent filing date for the continuation application is January 1, 2021.
• When a patent application is filed, it is given a filing date. This filing date is important because it determines the priority of the invention over other similar inventions that were filed after the parent filing date.

The examples illustrate that the parent filing date is the date when the original patent application was filed. It is used to determine the priority of the invention and to establish the date of constructivereduction to practice.