Skip to main content

Pitfalls When Refiling a Priority Application under Article 4 of the Paris Convention

Patent applicants who have filed a priority application (such as a U.S. Provisional application) may wish to abandon and then refile that priority application to extend the time available for filing a utility application.  This post discusses some of the pitfalls of pursuing such a strategy as well as ways to ensure that refiling a priority application does not endanger the right to eventually claim priority.

The United States (U.S.) and the European Patent Convention (EPC) (as well as most countries of the world) are party to the Paris Convention for the Protection of Industrial Property (“Paris Convention”), signed in Paris France on March 20, 1883.  The "Convention priority right," was established by Article 4 of this treaty. Article 4 provides that an applicant from one contracting State shall be able to use its first filing date (in one of the contracting States) as the effective filing date in another contracting State, provided that the applicant, or his successor in title, files a subsequent application within 12 months (for patents and utility models) from the date of the first filing.

Specifically, the priority right is established by Article 4(A) which states that “Any person who has duly filed an application for a patent, or for the registration of a utility model, or of an industrial design, or of a trademark, in one of the countries of the Union, or his successor in title, shall enjoy, for the purpose of filing in the other countries, a right of priority during the periods hereinafter fixed.”

Article 4(C)(4) permits a subsequently filed application to serve as the basis of priority so long as certain conditions are met with respect to the “first application” that was previously filed.   These conditions are:

at the time of filing the subsequent application, the said previous application has been withdrawn, abandoned, or refused, without having been laid open to public inspection and without leaving any rights outstanding, and if it has not yet served as a basis for claiming a right of priority. The previous application may not thereafter serve as a basis for claiming a right of priority.

Accordingly, Article 4(C)(4) defines the circumstances under which the convention priority year can be counted from a later filed application, provided at the filing of the later application the conditions of Article 4(C)(4) outlined above are met.

Based on Article 4(C)(4), a subsequently-filed priority application can serve as the basis for priority over an earlier-filed priority application if, at the time of filing the subsequent provisional, the first provisional 1) is abandoned (either by operation of law or expressly); 2) is unpublished (U.S. provisional applications are never published unless a utility application claims priority to them); 3) has no remaining rights; and 4) was not the basis of priority for a later-filed utility application.  Failure to ensure that each of these requirements is fulfilled could potentially jeopardize any application claiming priority to the subsequently-filed priority application.

The “no remaining rights” requirement is particularly important if the applicant is considering filing the application in Europe.  Similar to the Paris Convention, a European patent application must be filed within twelve months of the priority filing.  If the first application is abandoned, the applicant may still claim priority until the twelve month period.  However, even after twelve months, issues may arise. For example, under European practice, a request for re-establishment could be filed at the European Patent Office within two months from the missed deadline. Re-establishment has a strict standard and is rarely granted.  Nonetheless, it is possible to argue that, even though the twelve month deadline for filing a utility application had expired, there are still outstanding rights in the first filed application with regard to the possibility of re-establishing a priority claim.

Caution should also be taken under the scenario where, in the U.S., an applicant files, for example, three provisional applications (provisionals 1, 2, and 3) and then files a utility application claiming priority to only provisionals 2 and 3. If provisional 1 is still pending at the time provisional application 2 was filed, the priority claim to provisionals 2 and 3 will be endangered.  Applicants can prevent this scenario by expressly abandoning provisional 1 prior to filing the second and third provisional applications.

Therefore, based on the requirements outlined above, a best practice in these situations is to expressly abandon the first priority document prior to re-filing to ensure that the first application “has no remaining rights.”  It may also useful in Europe to specify in the express abandonment that the applicant is giving up “all remaining rights in the application, including the right to claim priority.”  Such language would bolster a patent applicant’s or patentee’s argument that all rights to the first-filed priority application had indeed been given up should any third party question the validity of an application’s or patent’s priority claim.

Subscribe To Viewpoints


Terri Shieh-Newton, PhD, is a Mintz Member who guides clients on portfolio management and landscape analysis. She's a trained immunologist with a PhD in Cellular and Molecular Medicine, and she works with companies of all sizes in a wide range of life sciences and clean technology industries.