What is Paris Convention Priority?
The 12-month right that holds every foreign filing program together, the 6-month rule for designs, and what happens when the date is missed.
Definition
Paris Convention priority is the right, under Article 4 of the Paris Convention for the Protection of Industrial Property, to file a patent application in any member country within 12 months of a first filing elsewhere and have the later application treated as if filed on the date of the first. For industrial designs and trademarks the period is 6 months.
Key Facts
- Treaty: Paris Convention of 1883, now with more than 175 member states
- Priority period: 12 months for patents and utility models; 6 months for designs and trademarks
- Measured from: The filing date of the first application for the invention in any member country, including a US provisional
- US implementation: 35 U.S.C. § 119(a) through (d)
- Restoration: Most offices, including the USPTO and EPO, allow restoration for up to 2 additional months if the miss was unintentional or, in some offices, despite due care
- Effect on term: The priority date does not start the 20-year term; the actual filing date in each country does
Why It Exists
Before the Paris Convention an inventor had to file in every country on the same day or risk the first filing becoming prior art against the others. The priority right lets an applicant file once, then spend a year deciding where else to file, refining the application, and raising money, with the first date protecting all of it against intervening disclosures and competing filings.
What the Priority Date Protects
During the 12 months, anything published or filed by others after the priority date cannot be cited against the later applications for subject matter that was in the first filing. The protection is only as broad as the first application's disclosure: new matter added in the foreign filing gets the foreign filing date, exactly as with a US provisional. Most offices also require that the priority application be the first filing for the invention anywhere; a second filing of the same matter does not restart the clock.
Formalities
- Priority claim: Must be made in the later application, usually within 16 months of the priority date, identifying the country, date, and number of the first filing
- Certified copy: A certified copy of the priority application is required; the WIPO Digital Access Service (DAS) lets offices retrieve it electronically using an access code
- Translation: Some offices require a translation of the priority document only if validity of the claim is challenged
The PCT Connection
The PCT application is itself a Paris Convention filing. Filing a PCT at month 12 claims priority once and extends the national decision to month 30, which is why the PCT route is the default for any program with more than a handful of countries. Whichever route is taken, the 12-month date is the hard stop for the whole foreign program, and docketing systems treat it accordingly.
Frequently Asked Questions
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How long is the Paris Convention priority period?
Twelve months for patents and utility models, and six months for industrial designs and trademarks, counted from the filing date of the first application in any member country.
What happens if you miss the 12-month priority deadline?
The priority claim is lost and the foreign application gets its own filing date. Any publication after the original date, including the applicant's own, becomes prior art. Many offices allow restoration within two further months if the delay was unintentional, and some require a showing of due care.
Does a US provisional application count as a Paris Convention filing?
Yes. A provisional establishes a priority date that can be claimed in foreign applications or a PCT application within 12 months, even though the provisional itself is never examined.
Does claiming priority change the patent term?
No. The 20-year term in each country runs from the actual filing date in that country (or the PCT filing date for national phase entries), not from the priority date. Priority only affects which prior art can be cited.
Is a certified copy of the priority document required?
Yes, in nearly every office. Most now accept electronic retrieval through the WIPO Digital Access Service, so the applicant registers the priority application with DAS and supplies the access code rather than mailing paper copies.
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