What happens to the priority date in a divisional application?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

The priority date of a divisional application remains the same as its parent application, provided that the proper procedures are followed. According to MPEP 201.06:

‘A later-filed application which is filed before the patenting or abandonment of or termination of proceedings on an earlier-filed application and which is an application for an invention which is disclosed and claimed in the earlier-filed application is an application for a ‘divisional’ of the earlier-filed application.’

This means that:

• The divisional application retains the priority date of the parent application for the subject matter disclosed in the parent.
• This is crucial for establishing the effective filing date for prior art purposes under 35 U.S.C. 100(i).
• The applicant must ensure that a proper reference to the parent application is made in the divisional to maintain this priority.

Maintaining the original priority date is one of the key advantages of filing a divisional application, as it allows the applicant to protect different aspects of their invention without losing the benefit of the earlier filing date.

For more information on Divisional application, visit: Divisional application.

For more information on effective filing date, visit: effective filing date.