Claiming Priority


The date you first file a patent application for your invention establishes what is known as a “priority date”.  Potential competitors who file an application at a later date for the same invention will not be entitled to a patent due to your earlier priority date. 

For example, if you had filed an application in respect of the same invention up to 12 months earlier in either Ireland, the European Patent Office or a country that is a party to the Paris Convention for the Protection of Industrial Property, the filing date of the earlier application becomes the "priority date" of your new application.

This period of 12 months allows an applicant for a patent, having established a filing date for their invention in one jurisdiction, time to assess its commercial potential market, continue the development of the invention and to decide in which countries protection is to be sought without losing their priority right. If there has been more than one earlier filing (e.g. if an application has been made in the UK and Germany in respect of the same invention) this can give rise to more than one priority date in respect of a subsequent Irish application; however, time limits which are started to run from the date of priority run from the earliest of such priority dates.

The main effect of the priority right is that the filing date of the first application counts as the date from which the state of the art is assessed against the application and where 2 or more persons make an invention independently, the right to a patent belongs to the person whose filing date or claimed priority date is the earliest.

Claim to priority

Any priority claim must be made in the request for grant (Form No. 1) indicating the date of filing, the country and filing number of the previous application. A certified copy of the previous application must also be supplied within 16 months of the earliest priority date, if it was a foreign application. This certified copy should be obtained from the Office abroad where this earlier application was made.

Where the claim to priority is based on an earlier Irish application, the applicant may, instead of submitting a certified copy, request that such a copy be included with their application. In this case the Intellectual Property Office of Ireland will arrange for a copy of the earlier application to be associated with the new application, on payment of the prescribed fee.