US Provisional Applications: Duration and Abandonment
Provisional applications in the US last only one year. If no utility or international application is filed during that one-year window, the provisional is abandoned. At that point it cannot be used to claim priority. Sometimes applicants are not ready to file a utility or international application during that year, so they re-file the provisional.
Risks of Re-Filing a Provisional
The problem arises if the re-filed provisional is submitted while the earlier provisional is still pending. Priority claims to the re-filed provisional may then fail in later national or regional phase applications.
Paris Convention Requirements for Priority Claims
Article 4(c)(4) of the Paris Convention states that a later-filed priority application can only claim priority over an earlier one if certain conditions are met. One condition is that no rights remain from the earlier application when the later one is filed.
European Patent Office: Re-Establishment Requests
In the European Patent Office (EPO), a request for re-establishment can be filed up to two months after the one-year window of the earlier provisional. If granted, rights from the earlier provisional remain, and priority to the later application would fail.
Best Practices for Provisional Filings
Best practice: if a re-filed provisional will serve as priority for a PCT application, the earlier pending provisional should be expressly abandoned first.
Kudos to Terri Shieh-Newton, PhD of Mintz-Levin for pointing out this problem.